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Posted on January 22, 2020 by sick skills — Leave a comment

Shipping API Integration in PHP with Australia Post Example

Last modified on January 22nd, 2020 by Vincy.

In an eCommerce website, we use the shipping API to calculate shipping cost. We calculate based on the items added to the shopping cart.

Integrating Shipping API with an eCommerce website will optimize the logistics cost. It takes care of the shipping needs in an effective way.

Shipping API integration helps eCommerce website by charging the right amount for shipping. Imagine when we add a random fixed cost to each checkout. What will happen is that, we will either overcharge the customer or end up in direct loss.

In this article, we will see how to integrate Australia Post shipping API in a PHP application. You can use this code in a shopping cart checkout page to calculate shipping rates.

I have created code to request the Australia Post API to calculate the shipping rates. This rate is for the products on domestic shipping.

What is inside?

What is Shipping API?

Shipping API – a digital intermediate as like as other APIs. It resolves eCommerce website shipping needs.

Integratable extern responds to the queries generated by the application.

With the available services and capabilities, it help build the eCommerce website’s shipping needs.

This ready-made solution will smoothen the customer’s buying experience with your online store.

Capabilities of Shipping APIs

For each eCommerce website, the motive to integrate Shipping API differs. This variation depends on the utilities required by the shopping cart.

In general, the capabilities of Shipping APIs are,

Verifying shipping zone
Multi-carrier support
Tracking the order traces during shipment.

With these capability limit, the Shipping APIs provides ultimate services. And, they are huge in number. For example,

Ensuring the shipping destination and thereby calculate the success probability of the delivery.
Request a quote for the carrier or shipment.
Receiving notification about tracking updates.

The Australia Post shipping API provides services like,

Postage assessment calculation
Postal code search
SecurePay online payments and more.

Existing shipping API available

Postal carrier APIs like DHL, USPS, Australia Post provides services for the eCommerce website. It offers services like calculating shipping rates, tracking shipped parcel and more.

There are numerous third-party shipping APIs available. For example Postmen, EasyPost, Shippo and more.

The third-party shipping API has a RESTful interface that connects postal service APIs. It creates a channel to read the API to access its functionalities.

About Australia Post API

Australia Post API suite has the following list APIs. All these APIs help to fulfil the transactional needs of your eCommerce website.

Postage assessment calculator – To get the cost for shipping a document or parcel.
Shipping and tracking – To get service on product dispatch and tracking.
SecurePay online payments – Payment solutions for an eCommerce website via SecurePay integration.
Delivery choices API – gives the delivery choices to the user to choose location, speed, day, date, time.

For accessing the API, it requires the corresponding API key. As per the Australia Post API access requirements it asks to register with the API to get the key.

Australia Post provides an interface to explore the APIs. You may generate live API requests via this explorer to see how it works.

About this example

In this example, it uses the Postage assessment calculator API or PAC of the Australia Post API suite.

This API provides services to calculate the shipping cost. This cost varies based on the parcel weight, dimension, and more parameters.

This API includes various endpoints returning resources data based on the access requests.

I am creating a request for calculating the shipping cost for a domestic parcel. This request needs the corresponding API key. In the next section, we will see how to get the API key for accessing the PAC API.

For this calculation, the API requires the parcel dimension, height, width. And also, it needs the shipping zone’s origin and destination postal codes. These are all common considering any eCommerce website.

I get the parameters from the user via an HTML form and send it with the API request.

This example uses PHP CURL to access the Australia Post Postage assessment calculator API.

File Structure

The below screenshot shows the Australia Post shipping rate calculation example files.

Australia Post shipping API integration steps

The steps to integrate Australia Post in an eCommerce website are,

Choose API from the Australia Post API suite.
Create a new account to get the API key.
Choose the postage service and set the endpoint.
Set the API key as the HTTP header AUTH-KEY.
Generate the PAC API request with the header set in step 4.

How to get the Australia Post PAC API key

There are many APIs provided by the Australia Post in API suite. The first step is to choose the API based on the need of your eCommerce website.

As discussed in the last section, I choose PAC API for calculating the shipping cost.

The PAC API access requirements state that it need the API key. This key is for authenticating the service request generated from the application.

On submitting valid information, it will send the API key to the registered email address. You can use this API then, to access the PAC API services.

Web interface to enter details to calculate shipping rates

This is the code to show a form to collect the product and shipping details.

It has the fields to collect the width, height, weight, and length of the parcel. The form will show the units of these parameters to the user.

Also, it collects the shipping address. This is the shipping destination address. The zip code is a mandatory field among the shipping address fields.

The shipping origin and destination postal codes are mandatory to calculate the rates.

In this example, the postal code of the shipping origin is configurable. You can also move it to the HTML form to let the user enter the data.

index.php

<HTML> <HEAD> <TITLE>Shipping API</TITLE> <link href="./assets/css/phppot-style.css" type="text/css" rel="stylesheet" /> <link href="./assets/css/shipping-api.css" type="text/css" rel="stylesheet" /> <script src="./vendor/jquery/jquery-3.3.1.js" type="text/javascript"></script> </HEAD> <BODY> <div class="phppot-container"> <div class="australian-api"> <div class="page-heading">Australian Shipping API</div> <form name="australian-api" id="australian-api" action="" method="post" onsubmit="return formValidation()"> <div class="sub-heading">Product Details</div> <div class="row"> <div class="inline-block"> <div class="form-label"> Length<span class="units-style">(cm)</span><span class="required error" id="length-info"></span> </div> <input class="input-box-110" type="text" name="length" id="length" value="<?php if(! empty($_POST["length"])){ echo $_POST["length"];}?>"> </div> <div class="inline-block input-right-margin"> <div class="form-label"> Width<span class="units-style">(cm)</span><span class="required error" id="width-info"></span> </div> <input class="input-box-110" type="text" name="width" id="width" value="<?php if(! empty($_POST["width"])){ echo $_POST["width"];}?>"> </div> <div class="inline-block"> <div class="form-label"> Height<span class="units-style">(cm)</span><span class="required error" id="height-info"></span> </div> <input class="input-box-110" type="text" name="height" id="height" value="<?php if(! empty($_POST["height"])){ echo $_POST["height"];}?>"> </div> <div class="inline-block input-right-margin"> <div class="form-label"> Weight<span class="units-style">(kg)</span><span class="required error" id="weight-info"></span> </div> <input class="input-box-110" type="text" name="weight" id="weight" value="<?php if(! empty($_POST["weight"])){ echo $_POST["weight"];}?>"> </div> </div> <div class="row"> <div class="inline-block"> <div class="form-label"> Quantity<span class="required error" id="quantity-info"></span> </div> <input class="input-box-110" type="number" name="quantity" id="quantity" value="<?php if(! empty($_POST["quantity"])){ echo $_POST["quantity"];}else{echo 1;}?>"> </div> </div> <div class="sub-heading">Shipping Address</div> <div class="row"> <div class="inline-block input-right-margin"> <div class="form-label">Address1</div> <input class="input-box-330" type="text" name="address1" id="address1" value="<?php if(! empty($_POST["address1"])){ echo $_POST["address1"];}?>"> </div> <div class="inline-block"> <div class="form-label">Address2</div> <input class="input-box-330" type="text" name="address2" id="address2" value="<?php if(! empty($_POST["address2"])){ echo $_POST["address2"];}?>"> </div> </div> <div class="row"> <div class="inline-block input-right-margin"> <div class="form-label">Country</div> <input class="input-box-330" type="text" name="country" id="country" value="<?php if(! empty($_POST["country"])){ echo $_POST["country"];}?>"> </div> <div class="inline-block"> <div class="form-label">State</div> <input class="input-box-330" type="text" name="state" id="state" value="<?php if(! empty($_POST["state"])){ echo $_POST["state"];}?>"> </div> </div> <div class="row"> <div class="inline-block input-right-margin"> <div class="form-label">City</div> <input class="input-box-330" type="text" name="city" id="city" value="<?php if(! empty($_POST["city"])){ echo $_POST["city"];}?>"> </div> <div class="inline-block"> <div class="form-label"> Zip Code<span class="required error" id="to-postcode-info"></span> </div> <input class="input-box-330" type="text" name="to-postcode" id="to-postcode" value="<?php if(! empty($_POST["to-postcode"])){ echo $_POST["to-postcode"];}?>"> </div> </div> <div class="row"> <div id="inline-block"> <input type="submit" class="submit-button" name="submit-btn" id="submit-btn" value="Get Quote"><span><img src="img/loader.gif" class="loader-ic" id="loader-icon"></span> </div> </div> </form> <?php if (! empty($shippingPrice)) { ?><div> <div class="sub-heading">Shipping Details</div> <div class="row"> <label class="shipping-result">Address1:</label> <?php echo $address1;?></div> <div class="row"> <label class="shipping-result">Address2:</label> <?php echo $address2;?></div> <div class="row"> <label class="shipping-result">Country:</label> <?php echo $country;?></div> <div class="row"> <label class="shipping-result">State:</label> <?php echo $state;?></div> <div class="row"> <label class="shipping-result">City:</label> <?php echo $city;?></div> <div class="row"> <label class="shipping-result">Quantity:</label> <?php echo $quantity;?></div> <div class="row"> <label class="shipping-result">Shipping price:</label> $<?php echo $quantity * $shippingPrice;?></div> </div> <?php }else if(!empty($errorMsg)){?> <div class="error-message"><?php echo $errorMsg;?></div> <?php }?> </div> </div> <script src="./assets/js/shipping.js"></script> </BODY> </HTML>

CSS created to present the payment form

This CSS includes basic styles to show the shipping form to the user. It has exclusive styles related to this example.

Apart from that, this example contains a generic CSS phppot-styles.css. It contains common template styles with a list of selectors. You can find this generic CSS in the downloadable source.

assets/css/shipping-api.css

.australian-api { background: #fff; border-radius: 4px; padding: 10px; width: 85%; margin: 20px 40px; } .page-heading { font-size: 2em; font-weight: bold; } .sub-heading { font-size: 1.2em; font-weight: bold; margin: 20px 0px; } .inline-block { display: inline-block; } .row { margin: 15px 0px; } .form-label { margin-bottom: 5px; text-align: left; } input.input-box-330 { width: 250px; } input.input-box-110 { width: 120px; margin-right: 5px; } .australian-api .error { color: #ee0000; padding: 0px; background: none; border: #ee0000; } .australian-api .error-field { border: 1px solid #d96557; } .australian-api .error:before { content: '*'; padding: 0 3px; color: #D8000C; } input.submit-button { background-color: #ffb932; border-color: #ffc87a #e2a348 #da9d0a; text-align: center; cursor: pointer; color: #000; width: 100px; } .input-right-margin { margin-right: 30px; } .shipping-result { font-weight: bold; color: #737171; padding: 15px 0px; } .error-message { color: #D8000C; } .units-style { font-size: 0.8em; color: #666; margin-left: 2px; } .loader-ic { display: none; }

jQuery script to validate the shipping details

The shipping.js file contains the form validation function. It validates the mandatory fields and makes sure that they are not empty.

It returns boolean based on which the form-post carried forward to PHP. While returning false, it highlights what’s wrong with the entered data.

After successful validation, PHP will validate the shipping attributes sent via the form.

assets/js/shipping.js

function formValidation() { var valid = true; $("#length").removeClass("error-field"); $("#width").removeClass("error-field"); $("#height").removeClass("error-field"); $("#weight").removeClass("error-field"); $("#quantity").removeClass("error-field"); $("#to-postcode").removeClass("error-field"); var Length = $("#length").val(); var Width = $("#width").val(); var Height = $("#height").val(); var Weight = $("#weight").val(); var Quantity = $("#quantity").val(); var toPostcode = $("#to-postcode").val(); if (Length.trim() == "") { $("#length-info").html("").css("color", "#ee0000").show(); $("#length").addClass("error-field"); valid = false; } if (Width.trim() == "") { $("#width-info").css("color", "#ee0000").show(); $("#width").addClass("error-field"); valid = false; } if (Height.trim() == "") { $("#height-info").css("color", "#ee0000").show(); $("#height").addClass("error-field"); valid = false; } if (Weight.trim() == "") { $("#weight-info").css("color", "#ee0000").show(); $("#weight").addClass("error-field"); valid = false; } if (Quantity.trim() == "" || Quantity < 1) { $("#quantity-info").css("color", "#ee0000").show(); $("#quantity").addClass("error-field"); valid = false; } if (toPostcode.trim() == "") { $("#to-postcode-info").css("color", "#ee0000").show(); $("#to-postcode").addClass("error-field"); valid = false; } if (valid == false) { $('.error-field').first().focus(); valid = false; } if (valid == true) { $("#submit-btn").hide(); $("#loader-icon").show(); } return valid; }

PHP code with Australia Post shipping API request-response handlers

This is the configuration file of this example code. It has the constants defined for keeping the API key and shipping origin.

Common/Config.php

<?php namespace Phppot; class Config { const AUSTRALIAN_POST_API_KEY = 'REPLACE_WITH_THE_API_KEY'; const SHIPPING_ORIGION = '1000'; } ?>

This is an exclusive service class for executing curl script. The execute() function is receiving URL, API KEY as its parameters.

It initiates curl object and set the URL. It sets the header with the API key to call the Australia Post live URL.

The rawBody will receive the API response in JSON format. You can use this as a sample to build an eCommerce website backed by a shopping cart with shipping API integration.

lib/CurlService.php

<?php namespace Phppot; class CurlService { public function execute($url, $apiKey, $ch = null) { if (is_null($ch)) { $ch = curl_init(); } curl_setopt($ch, CURLOPT_URL, $url); curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1); curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 0); curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false); curl_setopt($ch, CURLOPT_HTTPHEADER, array( 'AUTH-KEY: ' . $apiKey )); return $rawBody = curl_exec($ch); } } ?>

The AusPost.php PHP class handles the operation for preparing the API request.

The getShipmentPrice() function set the API key and form data to the PHP variables. It prepares the query parameters with these variables.

The class constructor instantiates the curlService created for this example.

Using the curl instance, it hits the Australia Post live PAC API URL. The API will validate the shipping criteria passed with the query parameters.

The request and response can be of either JSON or XML.

lib/AusPost.php

<?php namespace Phppot; class AusPost { private $curlService; private $api_url = 'https://digitalapi.auspost.com.au/postage/parcel/domestic/calculate?'; public function __construct() { require_once __DIR__ . '/CurlService.php'; $this->curlService = new CurlService(); } public function getShipmentPrice() { require_once __DIR__ . '/../Common/Config.php'; $con = new Config(); $apiKey = $con::AUSTRALIAN_POST_API_KEY; $fromPostcode = $con::SHIPPING_ORIGION; $toPostcode = $_POST["to-postcode"]; $length = $_POST["length"]; $width = $_POST["width"]; $height = $_POST["height"]; $weight = $_POST["weight"]; $queryParams = array( "from_postcode" => $fromPostcode, "to_postcode" => $toPostcode, "length" => $length, "width" => $width, "height" => $height, "weight" => $weight, "service_code" => "AUS_PARCEL_REGULAR" ); // here use $curlService and execute $url = $this->api_url . http_build_query($queryParams); $result = $this->curlService->execute($url, $apiKey); $shippingResult = json_decode($result); return $shippingResult; } } ?>

index.php (PHP Code)

<?php namespace Phppot; if (! empty($_POST["submit-btn"])) { require_once __DIR__ . '/lib/AusPost.php'; $shippingApi = new AusPost(); $result = $shippingApi->getShipmentPrice(); if (isset($result->postage_result)) { $shippingPrice = $result->postage_result->total_cost; } else { $errorMsg = $result->error->errorMessage; } $quantity = $_POST["quantity"]; $address1 = $_POST["address1"]; $address2 = $_POST["address2"]; $state = $_POST["state"]; $country = $_POST["country"]; $city = $_POST["city"]; } ?>

Australia Post shipping API integration output

The output screenshot below shows the payment and shipping form. It is to get the shipping details from the user.

It also has the fields to collect parameters like height, width and the dimension of the products.

You can also integrate this form into your shopping cart checkout page to calculate rates. For a shopping cart, it requires only the shipping address.

Because, the height, width, height will be a part of a product entity. And the quantity can be read from the cart session or database. The below form is generic and with little customization can be used for any eCommerce website.

Download

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Posted on January 18, 2020 by sick skills — Leave a comment

Python Regex Compile

Why have regular expressions survived seven decades of technological disruption? Because coders who understand regular expressions have a massive advantage when working with textual data. They can write in a single line of code what takes others dozens!

This article is all about the re.compile(pattern) method of Python’s re library. Before we dive into re.compile(), let’s get an overview of the four related methods you must understand:

The findall(pattern, string) method returns a list of string matches. Read more in our blog tutorial.
The search(pattern, string) method returns a match object of the first match. Read more in our blog tutorial.
The match(pattern, string) method returns a match object if the regex matches at the beginning of the string. Read more in our blog tutorial.
The fullmatch(pattern, string) method returns a match object if the regex matches the whole string. Read more in our blog tutorial.

Equipped with this quick overview of the most critical regex methods, let’s answer the following question:

How Does re.compile() Work in Python?

The re.compile(pattern) method returns a regular expression object (see next section)

You then use the object to call important regex methods such as search(string), match(string), fullmatch(string), and findall(string).

In short: You compile the pattern first. You search the pattern in a string second.

This two-step approach is more efficient than calling, say, search(pattern, string) at once. That is, IF you call the search() method multiple times on the same pattern. Why? Because you can reuse the compiled pattern multiple times.

Here’s an example:

import re # These two lines ...
regex = re.compile('Py...n')
match = regex.search('Python is great') # ... are equivalent to ...
match = re.search('Py...n', 'Python is great')

In both instances, the match variable contains the following match object:

<re.Match object; span=(0, 6), match='Python'>

But in the first case, we can find the pattern not only in the string ‘Python is great’ but also in other strings—without any redundant work of compiling the pattern again and again.

Specification:

re.compile(pattern, flags=0)

The method has up to two arguments.

pattern: the regular expression pattern that you want to match.
flags (optional argument): a more advanced modifier that allows you to customize the behavior of the function. Want to know how to use those flags? Check out this detailed article on the Finxter blog.

We’ll explore those arguments in more detail later.

Return Value:

The re.compile(patterns, flags) method returns a regular expression object. You may ask (and rightly so):

What’s a Regular Expression Object?

Python internally creates a regular expression object (from the Pattern class) to prepare the pattern matching process. You can call the following methods on the regex object:

Method	Description
`Pattern.search`(string[, pos[, endpos]])	Searches the regex anywhere in the string and returns a match object or None. You can define start and end positions of the search.
`Pattern.match`(string[, pos[, endpos]])	Searches the regex at the beginning of the string and returns a match object or None. You can define start and end positions of the search.
`Pattern.fullmatch`(string[, pos[, endpos]])	Matches the regex with the whole string and returns a match object or None. You can define start and end positions of the search.
`Pattern.split`(string, maxsplit=0)	Divides the string into a list of substrings. The regex is the delimiter. You can define a maximum number of splits.
`Pattern.findall`(string[, pos[, endpos]])	Searches the regex anywhere in the string and returns a list of matching substrings. You can define start and end positions of the search.
`Pattern.finditer`(string[, pos[, endpos]])	Returns an iterator that goes over all matches of the regex in the string (returns one match object after another). You can define the start and end positions of the search.
`Pattern.sub`(repl, string, count=0)	Returns a new string by replacing the first count occurrences of the regex in the string (from left to right) with the replacement string repl.
`Pattern.subn`(repl, string, count=0)	Returns a new string by replacing the first count occurrences of the regex in the string (from left to right) with the replacement string repl. However, it returns a tuple with the replaced string as the first and the number of successful replacements as the second tuple value.

If you’re familiar with the most basic regex methods, you’ll realize that all of them appear in this table. But there’s one distinction: you don’t have to define the pattern as an argument. For example, the regex method re.search(pattern, string) will internally compile a regex object p and then call p.search(string).

You can see this fact in the official implementation of the re.search(pattern, string) method:

def search(pattern, string, flags=0): """Scan through string looking for a match to the pattern, returning a Match object, or None if no match was found.""" return _compile(pattern, flags).search(string)

(Source: GitHub repository of the re package)

The re.search(pattern, string) method is a mere wrapper for compiling the pattern first and calling the p.search(string) function on the compiled regex object p.

Is It Worth Using Python’s re.compile()?

No, in the vast majority of cases, it’s not worth the extra line.

Consider the following example:

import re # These two lines ...
regex = re.compile('Py...n')
match = regex.search('Python is great') # ... are equivalent to ...
match = re.search('Py...n', 'Python is great')

Don’t get me wrong. Compiling a pattern once and using it many times throughout your code (e.g., in a loop) comes with a big performance benefit. In some anecdotal cases, compiling the pattern first lead to 10x to 50x speedup compared to compiling it again and again.

But the reason it is not worth the extra line is that Python’s re library ships with an internal cache. At the time of this writing, the cache has a limit of up to 512 compiled regex objects. So for the first 512 times, you can be sure when calling re.search(pattern, string) that the cache contains the compiled pattern already.

Here’s the relevant code snippet from re’s GitHub repository:

# --------------------------------------------------------------------
# internals _cache = {} # ordered! _MAXCACHE = 512
def _compile(pattern, flags): # internal: compile pattern if isinstance(flags, RegexFlag): flags = flags.value try: return _cache[type(pattern), pattern, flags] except KeyError: pass if isinstance(pattern, Pattern): if flags: raise ValueError( "cannot process flags argument with a compiled pattern") return pattern if not sre_compile.isstring(pattern): raise TypeError("first argument must be string or compiled pattern") p = sre_compile.compile(pattern, flags) if not (flags & DEBUG): if len(_cache) >= _MAXCACHE: # Drop the oldest item try: del _cache[next(iter(_cache))] except (StopIteration, RuntimeError, KeyError): pass _cache[type(pattern), pattern, flags] = p return p

Can you find the spots where the cache is initialized and used?

While in most cases, you don’t need to compile a pattern, in some cases, you should. These follow directly from the previous implementation:

You’ve got more than MAXCACHE patterns in your code.
You’ve got more than MAXCACHE different patterns between two same pattern instances. Only in this case, you will see “cache misses” where the cache has already flushed the seemingly stale pattern instances to make room for newer ones.
You reuse the pattern multiple times. Because if you don’t, it won’t make sense to use sparse memory to save them in your memory.
(Even then, it may only be useful if the patterns are relatively complicated. Otherwise, you won’t see a lot of performance benefits in practice.)

To summarize, compiling the pattern first and storing the compiled pattern in a variable for later use is often nothing but “premature optimization”—one of the deadly sins of beginner and intermediate programmers.

What Does re.compile() Really Do?

It doesn’t seem like a lot, does it? My intuition was that the real work is in finding the pattern in the text—which happens after compilation. And, of course, matching the pattern is the hard part. But a sensible compilation helps a lot in preparing the pattern to be matched efficiently by the regex engine—work that would otherwise have be done by the regex engine.

Regex’s compile() method does a lot of things such as:

Combine two subsequent characters in the regex if they together indicate a special symbol such as certain Greek symbols.
Prepare the regex to ignore uppercase and lowercase.
Check for certain (smaller) patterns in the regex.
Analyze matching groups in the regex enclosed in parentheses.

Here’s the implemenation of the compile() method—it looks more complicated than expected, no?

def _compile(code, pattern, flags): # internal: compile a (sub)pattern emit = code.append _len = len LITERAL_CODES = _LITERAL_CODES REPEATING_CODES = _REPEATING_CODES SUCCESS_CODES = _SUCCESS_CODES ASSERT_CODES = _ASSERT_CODES iscased = None tolower = None fixes = None if flags & SRE_FLAG_IGNORECASE and not flags & SRE_FLAG_LOCALE: if flags & SRE_FLAG_UNICODE: iscased = _sre.unicode_iscased tolower = _sre.unicode_tolower fixes = _ignorecase_fixes else: iscased = _sre.ascii_iscased tolower = _sre.ascii_tolower for op, av in pattern: if op in LITERAL_CODES: if not flags & SRE_FLAG_IGNORECASE: emit(op) emit(av) elif flags & SRE_FLAG_LOCALE: emit(OP_LOCALE_IGNORE[op]) emit(av) elif not iscased(av): emit(op) emit(av) else: lo = tolower(av) if not fixes: # ascii emit(OP_IGNORE[op]) emit(lo) elif lo not in fixes: emit(OP_UNICODE_IGNORE[op]) emit(lo) else: emit(IN_UNI_IGNORE) skip = _len(code); emit(0) if op is NOT_LITERAL: emit(NEGATE) for k in (lo,) + fixes[lo]: emit(LITERAL) emit(k) emit(FAILURE) code[skip] = _len(code) - skip elif op is IN: charset, hascased = _optimize_charset(av, iscased, tolower, fixes) if flags & SRE_FLAG_IGNORECASE and flags & SRE_FLAG_LOCALE: emit(IN_LOC_IGNORE) elif not hascased: emit(IN) elif not fixes: # ascii emit(IN_IGNORE) else: emit(IN_UNI_IGNORE) skip = _len(code); emit(0) _compile_charset(charset, flags, code) code[skip] = _len(code) - skip elif op is ANY: if flags & SRE_FLAG_DOTALL: emit(ANY_ALL) else: emit(ANY) elif op in REPEATING_CODES: if flags & SRE_FLAG_TEMPLATE: raise error("internal: unsupported template operator %r" % (op,)) if _simple(av[2]): if op is MAX_REPEAT: emit(REPEAT_ONE) else: emit(MIN_REPEAT_ONE) skip = _len(code); emit(0) emit(av[0]) emit(av[1]) _compile(code, av[2], flags) emit(SUCCESS) code[skip] = _len(code) - skip else: emit(REPEAT) skip = _len(code); emit(0) emit(av[0]) emit(av[1]) _compile(code, av[2], flags) code[skip] = _len(code) - skip if op is MAX_REPEAT: emit(MAX_UNTIL) else: emit(MIN_UNTIL) elif op is SUBPATTERN: group, add_flags, del_flags, p = av if group: emit(MARK) emit((group-1)*2) # _compile_info(code, p, _combine_flags(flags, add_flags, del_flags)) _compile(code, p, _combine_flags(flags, add_flags, del_flags)) if group: emit(MARK) emit((group-1)*2+1) elif op in SUCCESS_CODES: emit(op) elif op in ASSERT_CODES: emit(op) skip = _len(code); emit(0) if av[0] >= 0: emit(0) # look ahead else: lo, hi = av[1].getwidth() if lo != hi: raise error("look-behind requires fixed-width pattern") emit(lo) # look behind _compile(code, av[1], flags) emit(SUCCESS) code[skip] = _len(code) - skip elif op is CALL: emit(op) skip = _len(code); emit(0) _compile(code, av, flags) emit(SUCCESS) code[skip] = _len(code) - skip elif op is AT: emit(op) if flags & SRE_FLAG_MULTILINE: av = AT_MULTILINE.get(av, av) if flags & SRE_FLAG_LOCALE: av = AT_LOCALE.get(av, av) elif flags & SRE_FLAG_UNICODE: av = AT_UNICODE.get(av, av) emit(av) elif op is BRANCH: emit(op) tail = [] tailappend = tail.append for av in av[1]: skip = _len(code); emit(0) # _compile_info(code, av, flags) _compile(code, av, flags) emit(JUMP) tailappend(_len(code)); emit(0) code[skip] = _len(code) - skip emit(FAILURE) # end of branch for tail in tail: code[tail] = _len(code) - tail elif op is CATEGORY: emit(op) if flags & SRE_FLAG_LOCALE: av = CH_LOCALE[av] elif flags & SRE_FLAG_UNICODE: av = CH_UNICODE[av] emit(av) elif op is GROUPREF: if not flags & SRE_FLAG_IGNORECASE: emit(op) elif flags & SRE_FLAG_LOCALE: emit(GROUPREF_LOC_IGNORE) elif not fixes: # ascii emit(GROUPREF_IGNORE) else: emit(GROUPREF_UNI_IGNORE) emit(av-1) elif op is GROUPREF_EXISTS: emit(op) emit(av[0]-1) skipyes = _len(code); emit(0) _compile(code, av[1], flags) if av[2]: emit(JUMP) skipno = _len(code); emit(0) code[skipyes] = _len(code) - skipyes + 1 _compile(code, av[2], flags) code[skipno] = _len(code) - skipno else: code[skipyes] = _len(code) - skipyes + 1 else: raise error("internal: unsupported operand type %r" % (op,))

Don’t worry, you don’t need to understand the code. Just note that all this work would have to be done by the regex engine at “matching runtime” if you wouldn’t compile the pattern first. If we can do it only once, it’s certainly a low-hanging fruit for performance optimizations—especially for long regular expression patterns.

How to Use the Optional Flag Argument?

As you’ve seen in the specification, the compile() method comes with an optional third ‘flag’ argument:

re.compile(pattern, flags=0)

What’s the purpose of the flags argument?

Flags allow you to control the regular expression engine. Because regular expressions are so powerful, they are a useful way of switching on and off certain features (for example, whether to ignore capitalization when matching your regex).

Syntax	Meaning
re.ASCII	If you don’t use this flag, the special Python regex symbols w, W, b, B, d, D, s and S will match Unicode characters. If you use this flag, those special symbols will match only ASCII characters — as the name suggests.
re.A	Same as re.ASCII
re.DEBUG	If you use this flag, Python will print some useful information to the shell that helps you debugging your regex.
re.IGNORECASE	If you use this flag, the regex engine will perform case-insensitive matching. So if you’re searching for [A-Z], it will also match [a-z].
re.I	Same as re.IGNORECASE
re.LOCALE	Don’t use this flag — ever. It’s depreciated—the idea was to perform case-insensitive matching depending on your current locale. But it isn’t reliable.
re.L	Same as re.LOCALE
re.MULTILINE	This flag switches on the following feature: the start-of-the-string regex ‘^’ matches at the beginning of each line (rather than only at the beginning of the string). The same holds for the end-of-the-string regex ‘$’ that now matches also at the end of each line in a multi-line string.
re.M	Same as re.MULTILINE
re.DOTALL	Without using this flag, the dot regex ‘.’ matches all characters except the newline character ‘n’. Switch on this flag to really match all characters including the newline character.
re.S	Same as re.DOTALL
re.VERBOSE	To improve the readability of complicated regular expressions, you may want to allow comments and (multi-line) formatting of the regex itself. This is possible with this flag: all whitespace characters and lines that start with the character ‘#’ are ignored in the regex.
re.X	Same as re.VERBOSE

Here’s how you’d use it in a practical example:

import re text = 'Python is great (python really is)' regex = re.compile('Py...n', flags=re.IGNORECASE) matches = regex.findall(text)
print(matches)
# ['Python', 'python']

Although your regex ‘Python’ is uppercase, we ignore the capitalization by using the flag re.IGNORECASE.

Where to Go From Here?

You’ve learned about the re.compile(pattern) method that prepares the regular expression pattern—and returns a regex object which you can use multiple times in your code.

Learning Python is hard. But if you cheat, it isn’t as hard as it has to be:

Download 8 Free Python Cheat Sheets now!

Posted on January 17, 2020 by sick skills — Leave a comment

JetBrains Mono–A Font For Programmers

JetBrains, the makers of programmer tools such as IntelliJ, WebStorm, CLion and Rider, as well as the programming language Kotlin have been working on a font specifically designed for code. JetBrains Mono is an open source font family consisting of 8 fonts specifically designed with reading and writing code in mind.

Details from the JetBrains blog:

For the most part of our day we, as developers, look at the code. And it is no wonder that we are always on the lookout for the best font to make looking at the text on the screen easier on our eyes. However, the logic in many popular fonts does not always take into account the difference between reading through code and reading a book. Our eyes move along code in a very different way, often having to move vertically as often as they do horizontally, which is opposed to reading a book where they slide along the text always in the same direction.

Therefore, while working on JetBrains Mono we focused, among other things, on the issues that can cause eye fatigue during long sessions of working with code. We have considered things like the size and shape of letters; the amount of space between them, a balance naturally engineered in monospace fonts; unnecessary details and unclear distinctions between symbols, such as I’s and l’s for example; and programming ligatures when developing our font.

Today, we proudly present JetBrains Mono – a new open-source typeface specifically made for developers. Check out what makes JetBrains Mono unique in the big family of monospaced fonts and try it in your favorite code editor. Have a look at JetBrains Mono, your eyes will thank you for it.

More details about Mono are available here. It is the default font on all 2020 JetBrains IDEs and is available as an option in version 2019.3 and beyond of all JetBrain products. If you use another IDE you can download the zip here. Learn more about JetBrains Mono, including how to install and configure in Visual Studio Code in the video below.

[youtube https://www.youtube.com/watch?v=AyCZ0dVlz4A&w=853&h=480]

Programming GameDev News

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Posted on January 14, 2020 by sick skills — Leave a comment

Announcing Experimental Mobile Blazor Bindings

Eilon

January 14th, 2020

Today I’m excited to announce a new experimental project to enable native mobile app development with Blazor: Experimental Mobile Blazor Bindings. These bindings enable developers to build native mobile apps using C# and .NET for iOS and Android using familiar web programming patterns. This means you can use the Blazor programming model and Razor syntax to define UI components and behaviors of an application. The UI components that are included are based on Xamarin.Forms native UI controls, which results in beautiful native mobile apps.

Here is a sample Counter component, which may look familiar to Blazor developers, that increments a value on each button press:

<StackLayout> <Label FontSize="30" Text="@("You pressed " + count + " times")" /> <Button Text="+1" OnClick="@HandleClick" />
</StackLayout> @code { int count; void HandleClick() { count++; }
}

Notice that the Blazor model is present with code sitting side by side the user interface markup that leverages Razor syntax with mobile specific components. This will feel very natural for any web developer that has ever used Razor syntax in the past. Now with the Experimental Mobile Blazor Bindings you can leverage your existing web skills and knowledge to build native iOS and Android apps powered by .NET.

Here is the code above running in the Android Emulator:

Get started with Mobile Blazor Bindings

To get started, all you need is the .NET Core 3.0 or 3.1 SDK, Visual Studio or Visual Studio for Mac, and the ASP.NET and web development and Mobile development with .NET (Xamarin.Forms) workloads installed.

Install the templates by running this command from a command/shell window:

dotnet new -i Microsoft.MobileBlazorBindings.Templates::0.1.173-beta

And then create your first project by running this command:

dotnet new mobileblazorbindings -o MyApp

Open the solution (SLN file) in Visual Studio and mark either the Android or iOS project as the StartUp Project, which should look like this:

Now run your first Mobile Blazor Bindings app in a local emulator or on an attached mobile device! Don’t have one set up yet for development? No worries, the Xamarin documentation has all the details for you here:

For documentation and walkthroughs, check out the Mobile Blazor Bindings documentation.

Why Mobile Blazor Bindings now?

Many developers delight in using XAML and Xamarin.Forms to craft beautiful native mobile apps. We have heard from a set of developers that come from a web programming background that having web specific patterns to build mobile applications would be ideal for them. The goal of these bindings is to see if developers would like to have the option of writing markup and doing data binding for native mobile applications using the Blazor-style programming model with Razor syntax and features. Would you love to see this option in the box for future versions of Visual Studio?

Learn more

To learn more about Experimental Mobile Blazor Bindings, please check out these resources:

Give feedback

Please send us your feedback via issues in our GitHub repo and by completing a short survey about your experience and expectations.

We hope you try out this new framework and let us know your thoughts!

Posted on January 12, 2020 by sick skills — Leave a comment

Python Regex Fullmatch

This article is all about the re.fullmatch(pattern, string) method of Python’s re library. There are three similar methods to help you use regular expressions:

The findall(pattern, string) method returns a list of string matches. Check out our blog tutorial.
The search(pattern, string) method returns a match object of the first match. Check out our blog tutorial.
The match(pattern, string) method returns a match object if the regex matches at the beginning of the string. Check out our blog tutorial.

So how does the re.fullmatch() method work? Let’s study the specification.

How Does re.fullmatch() Work in Python?

The re.fullmatch(pattern, string) method returns a match object if the pattern matches the whole string.

Specification:

re.fullmatch(pattern, string, flags=0)

The re.fullmatch() method has up to three arguments.

pattern: the regular expression pattern that you want to match.
string: the string which you want to search for the pattern.
flags (optional argument): a more advanced modifier that allows you to customize the behavior of the function. Want to know how to use those flags? Check out this detailed article on the Finxter blog.

We’ll explore them in more detail later.

Return Value:

The re.fullmatch() method returns a match object. You may ask (and rightly so):

What’s a Match Object?

If a regular expression matches a part of your string, there’s a lot of useful information that comes with it: what’s the exact position of the match? Which regex groups were matched—and where?

The match object is a simple wrapper for this information. Some regex methods of the re package in Python—such as fullmatch()—automatically create a match object upon the first pattern match.

At this point, you don’t need to explore the match object in detail. Just know that we can access the start and end positions of the match in the string by calling the methods m.start() and m.end() on the match object m:

>>> m = re.fullmatch('h...o', 'hello')
>>> m.start()
0
>>> m.end()
5

In the first line, you create a match object m by using the re.fullmatch() method. The pattern ‘h…o’ matches in the string ‘hello’ at start position 0 and end position 5. But note that as the fullmatch() method always attempts to match the whole string, the m.start() method will always return zero.

Now, you know the purpose of the match object in Python. Let’s check out a few examples of re.fullmatch()!

A Guided Example for re.fullmatch()

First, you import the re module and create the text string to be searched for the regex patterns:

>>> import re
>>> text = '''
Call me Ishmael. Some years ago--never mind how long precisely
--having little or no money in my purse, and nothing particular
to interest me on shore, I thought I would sail about a little
and see the watery part of the world. '''

Let’s say you want to match the full text with this regular expression:

>>> re.fullmatch('Call(.|\n)*', text)
>>>

The first argument is the pattern to be found: 'Call(.|\n)*'. The second argument is the text to be analyzed. You stored the multi-line string in the variable text—so you take this as the second argument. The third argument flags of the fullmatch() method is optional and we skip it in the code.

There’s no output! This means that the re.fullmatch() method did not return a match object. Why? Because at the beginning of the string, there’s no match for the ‘Call’ part of the regex. The regex starts with an empty line!

So how can we fix this? Simple, by matching a new line character ‘\n’ at the beginning of the string.

>>> re.fullmatch('\nCall(.|\n)*', text)
<re.Match object; span=(0, 229), match='\nCall me Ishmael. Some years ago--never mind how>

The regex (.|\n)* matches an arbitrary number of characters (new line characters or not) after the prefix ‘\nCall’. This matches the whole text so the result is a match object. Note that there are 229 matching positions so the string included in resulting match object is only the prefix of the whole matching string. This fact is often overlooked by beginner coders.

What’s the Difference Between re.fullmatch() and re.match()?

The methods re.fullmatch() and re.match(pattern, string) both return a match object. Both attempt to match at the beginning of the string. The only difference is that re.fullmatch() also attempts to match the end of the string as well: it wants to match the whole string!

You can see this difference in the following code:

>>> text = 'More with less'
>>> re.match('More', text)
<re.Match object; span=(0, 4), match='More'>
>>> re.fullmatch('More', text)
>>>

The re.match(‘More’, text) method matches the string ‘More’ at the beginning of the string ‘More with less’. But the re.fullmatch(‘More’, text) method does not match the whole text. Therefore, it returns the None object—nothing is printed to your shell!

What’s the Difference Between re.fullmatch() and re.findall()?

There are two differences between the re.fullmatch(pattern, string) and re.findall(pattern, string) methods:

re.fullmatch(pattern, string) returns a match object while re.findall(pattern, string) returns a list of matching strings.
re.fullmatch(pattern, string) can only match the whole string, while re.findall(pattern, string) can return multiple matches in the string.

Both can be seen in the following example:

>>> text = 'the 42th truth is 42'
>>> re.fullmatch('.*?42', text)
<re.Match object; span=(0, 20), match='the 42th truth is 42'>
>>> re.findall('.*?42', text)
['the 42', 'th truth is 42']

Note that the regex .*? matches an arbitrary number of characters but it attempts to consume as few characters as possible. This is called “non-greedy” match (the *? operator). The fullmatch() method only returns a match object that matches the whole string. The findall() method returns a list of all occurrences. As the match is non-greedy, it finds two such matches.

What’s the Difference Between re.fullmatch() and re.search()?

The methods re.fullmatch() and re.search(pattern, string) both return a match object. However, re.fullmatch() attempts to match the whole string while re.search() matches anywhere in the string.

You can see this difference in the following code:

>>> text = 'Finxter is fun!'
>>> re.search('Finxter', text)
<re.Match object; span=(0, 7), match='Finxter'>
>>> re.fullmatch('Finxter', text)
>>>

The re.search() method retrieves the match of the ‘Finxter’ substring as a match object. But the re.fullmatch() method has no return value because the substring ‘Finxter’ does not match the whole string ‘Finxter is fun!’.

How to Use the Optional Flag Argument?

As you’ve seen in the specification, the fullmatch() method comes with an optional third ‘flag’ argument:

re.fullmatch(pattern, string, flags=0)

What’s the purpose of the flags argument?

Syntax	Meaning
re.ASCII	If you don’t use this flag, the special Python regex symbols w, W, b, B, d, D, s and S will match Unicode characters. If you use this flag, those special symbols will match only ASCII characters — as the name suggests.
re.A	Same as re.ASCII
re.DEBUG	If you use this flag, Python will print some useful information to the shell that helps you debugging your regex.
re.IGNORECASE	If you use this flag, the regex engine will perform case-insensitive matching. So if you’re searching for [A-Z], it will also match [a-z].
re.I	Same as re.IGNORECASE
re.LOCALE	Don’t use this flag — ever. It’s depreciated—the idea was to perform case-insensitive matching depending on your current locale. But it isn’t reliable.
re.L	Same as re.LOCALE
re.MULTILINE	This flag switches on the following feature: the start-of-the-string regex ‘^’ matches at the beginning of each line (rather than only at the beginning of the string). The same holds for the end-of-the-string regex ‘$’ that now matches also at the end of each line in a multi-line string.
re.M	Same as re.MULTILINE
re.DOTALL	Without using this flag, the dot regex ‘.’ matches all characters except the newline character ‘n’. Switch on this flag to really match all characters including the newline character.
re.S	Same as re.DOTALL
re.VERBOSE	To improve the readability of complicated regular expressions, you may want to allow comments and (multi-line) formatting of the regex itself. This is possible with this flag: all whitespace characters and lines that start with the character ‘#’ are ignored in the regex.
re.X	Same as re.VERBOSE

Here’s how you’d use it in a practical example:

>>> text = 'Python is great!'
>>> re.search('PYTHON', text, flags=re.IGNORECASE)
<re.Match object; span=(0, 6), match='Python'>

Although your regex ‘PYTHON’ is all-caps, we ignore the capitalization by using the flag re.IGNORECASE.

Where to Go From Here?

This article has introduced the re.fullmatch(pattern, string) method that attempts to match the whole string—and returns a match object if it succeeds or None if it doesn’t.

Learning Python is hard. But if you cheat, it isn’t as hard as it has to be:

Download 8 Free Python Cheat Sheets now!

Posted on January 10, 2020 by sick skills — Leave a comment

Python Regex Match

This article is all about the match() method of Python’s re library. There are two similar methods to help you use regular expressions:

The easy-to-use but less powerful findall() method returns a list of string matches. Check out our blog tutorial.
The search() method returns a match object of the first match. Check out our blog tutorial.

So how does the re.match() method work? Let’s study the specification.

How Does re.match() Work in Python?

The re.match(pattern, string) method matches the pattern at the beginning of the string and returns a match object.

Specification:

re.match(pattern, string, flags=0)

The re.match() method has up to three arguments.

pattern: the regular expression pattern that you want to match.
string: the string which you want to search for the pattern.
flags (optional argument): a more advanced modifier that allows you to customize the behavior of the function. Want to know how to use those flags? Check out this detailed article on the Finxter blog.

We’ll explore them in more detail later.

Return Value:

The re.match() method returns a match object. You may ask (and rightly so):

What’s a Match Object?

If a regular expression matches a part of your string, there’s a lot of useful information that comes with it: what’s the exact position of the match? Which regex groups were matched—and where?

The match object is a simple wrapper for this information. Some regex methods of the re package in Python—such as match()—automatically create a match object upon the first pattern match.

>>> m = re.match('h...o', 'hello world')
>>> m.start()
0
>>> m.end()
5
>>> 'hello world'[m.start():m.end()] 'hello'

In the first line, you create a match object m by using the re.match() method. The pattern ‘h…o’ matches in the string ‘hello world’ at start position 0. You use the start and end position to access the substring that matches the pattern (using the popular Python technique of slicing). But note that as the match() method always attempts to match only at the beginning of the string, the m.start() method will always return zero.

Now, you know the purpose of the match() object in Python. Let’s check out a few examples of re.match()!

A Guided Example for re.match()

First, you import the re module and create the text string to be searched for the regex patterns:

>>> import re
>>> text = ''' Ha! let me see her: out, alas! he's cold: Her blood is settled, and her joints are stiff; Life and these lips have long been separated: Death lies on her like an untimely frost Upon the sweetest flower of all the field. '''

Let’s say you want to search the text for the string ‘her’:

>>> re.match('lips', text)
>>>

The first argument is the pattern to be found: the string ‘lips’. The second argument is the text to be analyzed. You stored the multi-line string in the variable text—so you take this as the second argument. The third argument flags of the match() method is optional.

There’s no output! This means that the re.match() method did not return a match object. Why? Because at the beginning of the string, there’s no match for the regex pattern ‘lips’.

So how can we fix this? Simple, by matching all the characters that preced the string ‘lips’ in the text:

>>> re.match('(.|\n)*lips', text)
<re.Match object; span=(0, 122), match="\n Ha! let me see her: out, alas! he's cold:\n>

The regex (.|\n)*lips matches all prefixes (an arbitrary number of characters including new lines) followed by the string ‘lips’. This results in a new match object that matches a huge substring from position 0 to position 122. Note that the match object doesn’t print the whole substring to the shell. If you access the matched substring, you’ll get the following result:

>>> m = re.match('(.|\n)*lips', text)
>>> text[m.start():m.end()] "\n Ha! let me see her: out, alas! he's cold:\n Her blood is settled, and her joints are stiff;\n Life and these lips"

Interestingly, you can also achieve the same thing by specifying the third flag argument as follows:

>>> m = re.match('.*lips', text, flags=re.DOTALL)
>>> text[m.start():m.end()] "\n Ha! let me see her: out, alas! he's cold:\n Her blood is settled, and her joints are stiff;\n Life and these lips"

The re.DOTALL flag ensures that the dot operator . matches all characters including the new line character.

What’s the Difference Between re.match() and re.findall()?

There are two differences between the re.match(pattern, string) and re.findall(pattern, string) methods:

re.match(pattern, string) returns a match object while re.findall(pattern, string) returns a list of matching strings.
re.match(pattern, string) returns only the first match in the string—and only at the beginning—while re.findall(pattern, string) returns all matches in the string.

Both can be seen in the following example:

>>> text = 'Python is superior to Python'
>>> re.match('Py...n', text)
<re.Match object; span=(0, 6), match='Python'>
>>> re.findall('Py...n', text)
['Python', 'Python']

The string ‘Python is superior to Python’ contains two occurrences of ‘Python’. The match() method only returns a match object of the first occurrence. The findall() method returns a list of all occurrences.

What’s the Difference Between re.match() and re.search()?

The methods re.search(pattern, string) and re.match(pattern, string) both return a match object of the first match. However, re.match() attempts to match at the beginning of the string while re.search() matches anywhere in the string.

You can see this difference in the following code:

>>> text = 'Slim Shady is my name'
>>> re.search('Shady', text)
<re.Match object; span=(5, 10), match='Shady'>
>>> re.match('Shady', text)
>>>

The re.search() method retrieves the match of the ‘Shady’ substring as a match object. But if you use the re.match() method, there is no match and no return value because the substring ‘Shady’ does not occur at the beginning of the string ‘Slim Shady is my name’.

How to Use the Optional Flag Argument?

As you’ve seen in the specification, the match() method comes with an optional third ‘flag’ argument:

re.match(pattern, string, flags=0)

What’s the purpose of the flags argument?

Syntax	Meaning
re.ASCII	If you don’t use this flag, the special Python regex symbols w, W, b, B, d, D, s and S will match Unicode characters. If you use this flag, those special symbols will match only ASCII characters — as the name suggests.
re.A	Same as re.ASCII
re.DEBUG	If you use this flag, Python will print some useful information to the shell that helps you debugging your regex.
re.IGNORECASE	If you use this flag, the regex engine will perform case-insensitive matching. So if you’re searching for [A-Z], it will also match [a-z].
re.I	Same as re.IGNORECASE
re.LOCALE	Don’t use this flag — ever. It’s depreciated—the idea was to perform case-insensitive matching depending on your current locale. But it isn’t reliable.
re.L	Same as re.LOCALE
re.MULTILINE	This flag switches on the following feature: the start-of-the-string regex ‘^’ matches at the beginning of each line (rather than only at the beginning of the string). The same holds for the end-of-the-string regex ‘$’ that now matches also at the end of each line in a multi-line string.
re.M	Same as re.MULTILINE
re.DOTALL	Without using this flag, the dot regex ‘.’ matches all characters except the newline character ‘n’. Switch on this flag to really match all characters including the newline character.
re.S	Same as re.DOTALL
re.VERBOSE	To improve the readability of complicated regular expressions, you may want to allow comments and (multi-line) formatting of the regex itself. This is possible with this flag: all whitespace characters and lines that start with the character ‘#’ are ignored in the regex.
re.X	Same as re.VERBOSE

Here’s how you’d use it in a practical example:

>>> text = 'Python is great!'
>>> re.search('PYTHON', text, flags=re.IGNORECASE)
<re.Match object; span=(0, 6), match='Python'>

Although your regex ‘PYTHON’ is all-caps, we ignore the capitalization by using the flag re.IGNORECASE.

Where to Go From Here?

This article has introduced the re.match(pattern, string) method that attempts to match the first occurrence of the regex pattern at the beginning of a given string—and returns a match object.

Python soars in popularity. There are two types of people: those who understand coding and those who don’t. The latter will have larger and larger difficulties participating in the era of massive adoption and penetration of digital content. Do you want to increase your Python skills daily without investing a lot of time?

Then join my “Coffee Break Python” email list of tens of thousands of ambitious coders!

Posted on January 10, 2020 by sick skills — Leave a comment

Building ArmorPaint From Source

ArmorPaint is an open source competitor to Substance Painter, from the creator of the Armory game engine (tutorial series available here). It is available for just 16 Euro in binary form, but can also be built from source code. This guide walks you step by step through the process of building ArmorPaint from source.

There are a few requirements before you can build. Download and install the following programs if not already installed:

First step, we clone the repository. Make sure to add the –recursive flag(that’s two ‘-‘ by the way).

Open a command prompt, cd to the directory where you want to install ArmorPaint’s source code and run the command:

git clone –recursive https://github.com/armory3d/armorpaint.git

Depending on your internet speed this could take a minute to several minutes while all of the files are downloaded.

In Explorer, go the installation directory, then navigate to armorpaint\Kromx\V8\Libraries\win32\release and using 7zip extract v8_monolith.7z to the same directory as the .7z file.

Next in the command prompt run the following commands

(Assuming you are reusing the same CMD that you did the git clone from)

cd armorpaint

node Kromx/make –g direct3d11

cd Kromx

node Kinc/make –g direct3d11

explorer .

If you receive any errors above, the most likely cause is node not being installed. The final command will now open a Windows Explorer window in the Kromx subdirectory. Open the build directory and load the file Krom.sln.

This will open the project in Visual Studio. If you haven’t run VS yet,you may have to do some initial installation steps. Worst case scenario run through the initial install, close and double click Krom.sln again.

First make sure that you are building for x64 and Release mode at the top:

In the Solution Explorer, select Krom then hit ALT + ENTER or right click and select Properties.

Then select Debugging, in Command Arguments enter ..\..\build.krom then click Apply.

You are now ready to build ArmorPaint. Select Ctrl + SHIFT + B or select Build->Build Solution.

Assuming no errors, are exe should be built. Now go to the folder armorpaint\Kromx\build\x64\Release and copy the file Krom.exe, then copy to armorpaint\build\krom. You can now run Krom.exe and you’re good to go.

Step by step instructions are available in the video below.

[youtube https://www.youtube.com/watch?v=y6h2KOP47ZY&w=853&h=480]

Art Programming 3D Applications

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Posted on January 9, 2020 by sick skills — Leave a comment

Python Regex Search

When I first learned about regular expressions, I didn’t appreciate their power. But there’s a reason regular expressions have survived seven decades of technological disruption: coders who understand regular expressions have a massive advantage when working with textual data. They can write in a single line of code what takes others dozens!

This article is all about the search() method of Python’s re library. To learn about the easy-to-use but less powerful findall() method that returns a list of string matches, check out our article about the similar findall() method.

So how does the re.search() method work? Let’s study the specification.

How Does re.search() Work in Python?

The re.search(pattern, string) method matches the first occurrence of the pattern in the string and returns a match object.

Specification:

re.search(pattern, string, flags=0)

The re.search() method has up to three arguments.

pattern: the regular expression pattern that you want to match.
string: the string which you want to search for the pattern.
flags (optional argument): a more advanced modifier that allows you to customize the behavior of the function. Want to know how to use those flags? Check out this detailed article on the Finxter blog.

We’ll explore them in more detail later.

Return Value:

The re.search() method returns a match object. You may ask (and rightly so):

What’s a Match Object?

If a regular expression matches a part of your string, there’s a lot of useful information that comes with it: what’s the exact position of the match? Which regex groups were matched—and where?

The match object is a simple wrapper for this information. Some regex methods of the re package in Python—such as search()—automatically create a match object upon the first pattern match.

>>> m = re.search('h...o', 'hello world')
>>> m.start()
0
>>> m.end()
5
>>> 'hello world'[m.start():m.end()] 'hello'

In the first line, you create a match object m by using the re.search() method. The pattern ‘h…o’ matches in the string ‘hello world’ at start position 0. You use the start and end position to access the substring that matches the pattern (using the popular Python technique of slicing).

Now, you know the purpose of the match() object in Python. Let’s check out a few examples of re.search()!

A Guided Example for re.search()

First, you import the re module and create the text string to be searched for the regex patterns:

>>> import re
>>> text = ''' Ha! let me see her: out, alas! he's cold: Her blood is settled, and her joints are stiff; Life and these lips have long been separated: Death lies on her like an untimely frost Upon the sweetest flower of all the field. '''

Let’s say you want to search the text for the string ‘her’:

>>> re.search('her', text)
<re.Match object; span=(20, 23), match='her'>

The first argument is the pattern to be found. In our case, it’s the string ‘her’. The second argument is the text to be analyzed. You stored the multi-line string in the variable text—so you take this as the second argument. You don’t need to define the optional third argument flags of the search() method because you’re fine with the default behavior in this case.

Look at the output: it’s a match object! The match object gives the span of the match—that is the start and stop indices of the match. We can also directly access those boundaries by using the start() and stop() methods of the match object:

>>> m = re.search('her', text)
>>> m.start()
20
>>> m.end()
23

The problem is that the search() method only retrieves the first occurrence of the pattern in the string. If you want to find all matches in the string, you may want to use the findall() method of the re library.

What’s the Difference Between re.search() and re.findall()?

There are two differences between the re.search(pattern, string) and re.findall(pattern, string) methods:

re.search(pattern, string) returns a match object while re.findall(pattern, string) returns a list of matching strings.
re.search(pattern, string) returns only the first match in the string while re.findall(pattern, string) returns all matches in the string.

Both can be seen in the following example:

>>> text = 'Python is superior to Python'
>>> re.search('Py...n', text)
<re.Match object; span=(0, 6), match='Python'>
>>> re.findall('Py...n', text)
['Python', 'Python']

The string ‘Python is superior to Python’ contains two occurrences of ‘Python’. The search() method only returns a match object of the first occurrence. The findall() method returns a list of all occurrences.

What’s the Difference Between re.search() and re.match()?

You can see this difference in the following code:

>>> text = 'Slim Shady is my name'
>>> re.search('Shady', text)
<re.Match object; span=(5, 10), match='Shady'>
>>> re.match('Shady', text)
>>>

How to Use the Optional Flag Argument?

As you’ve seen in the specification, the search() method comes with an optional third ‘flag’ argument:

re.search(pattern, string, flags=0)

What’s the purpose of the flags argument?

Syntax	Meaning
re.ASCII	If you don’t use this flag, the special Python regex symbols \w, \W, \b, \B, \d, \D, \s and \S will match Unicode characters. If you use this flag, those special symbols will match only ASCII characters — as the name suggests.
re.A	Same as re.ASCII
re.DEBUG	If you use this flag, Python will print some useful information to the shell that helps you debugging your regex.
re.IGNORECASE	If you use this flag, the regex engine will perform case-insensitive matching. So if you’re searching for [A-Z], it will also match [a-z].
re.I	Same as re.IGNORECASE
re.LOCALE	Don’t use this flag — ever. It’s depreciated—the idea was to perform case-insensitive matching depending on your current locale. But it isn’t reliable.
re.L	Same as re.LOCALE
re.MULTILINE	This flag switches on the following feature: the start-of-the-string regex ‘^’ matches at the beginning of each line (rather than only at the beginning of the string). The same holds for the end-of-the-string regex ‘$’ that now matches also at the end of each line in a multi-line string.
re.M	Same as re.MULTILINE
re.DOTALL	Without using this flag, the dot regex ‘.’ matches all characters except the newline character ‘\n’. Switch on this flag to really match all characters including the newline character.
re.S	Same as re.DOTALL
re.VERBOSE	To improve the readability of complicated regular expressions, you may want to allow comments and (multi-line) formatting of the regex itself. This is possible with this flag: all whitespace characters and lines that start with the character ‘#’ are ignored in the regex.
re.X	Same as re.VERBOSE

Here’s how you’d use it in a practical example:

>>> text = 'Python is great!'
>>> re.search('PYTHON', text, flags=re.IGNORECASE)
<re.Match object; span=(0, 6), match='Python'>

Although your regex ‘PYTHON’ is all-caps, we ignore the capitalization by using the flag re.IGNORECASE.

Where to Go From Here?

This article has introduced the re.search(pattern, string) method that attempts to match the first occurrence of the regex pattern in a given string—and returns a match object.

Then join my “Coffee Break Python” email list of tens of thousands of ambitious coders!

Posted on January 9, 2020 by sick skills — Leave a comment

Contact Form with Custom Image Captcha Validation like Google reCaptcha

Last modified on January 9th, 2020 by Vincy.

A contact form on a website is a medium to the users to contact the site admin or maintainer. It acts as a medium of communication. For many a websites, it is a critical factor in getting a sale.

The Captcha in a form is a mechanism to prevent bots or malicious users from submitting the form. It protects the site from security abuses.

There are components available in the market to render captcha in a form. Google reCAPTCHA is a popular and unbeatable service to make your form captcha-enabled.

Different websites use different types of captcha.
Displaying random alpha-numeric characters.
Requesting to solve puzzles, Google reCAPTCHA-like image captcha.

I created an example code for a contact form in PHP with the reCAPTCHA-like image captcha mechanism.

What is inside?

Ready-made contact form components are existing huge in number around the web. If you want to get one among them, then we need to be sure about the security and robustness of the code.

I have created a secure spam-free contact form script, Iris. I coded this component to easily integrate and configure with your application. If you are looking for a contact form that controls spam without using a captcha, then you will like it.

This also component includes Google reCAPTCHA. You can enable or disable this feature on a need basis. In similar ways, it comes with loads of features that is configurable in minutes.

About this example

This example code has the Name, Email, Subject and Message fields. These are some basic fields that we have seen with other PHP contact form example earlier.

Added to these fields, I have added an image captcha section in this code. This section will show five random images and ask to choose one. The random images are from the database.

I used jQuery script to validate the form field data before posting it to the PHP.

In PHP, it validates the captcha image clicked by the user. Based on the server-side captcha validation, the PHP will respond to the user.

File structure

The PHP contact form with an image captcha example includes less number of files.

The file structure is in the below screenshot. You can see that it has a systematic code with a conventional structure.

This code snippet shows the HTML part of the index.php, the landing page.

This contact form contains some basic fields with custom captcha in PHP.

The captcha section shows the SVG image markup from the database. It displays five random images and requests the user to select one.

The HTML form has the specification of a jQuery validation handler. The form-submit event will invoke this handler to process the form validation.

This HTML includes the response containers to display notifications to the user. These notifications acknowledge the user about the captcha validation or other responses.

index.php (contact form HTML)

<html> <head> <title>Contact Us Form</title> <link rel="stylesheet" type="text/css" href="assets/css/contact-form-style.css" /> <link rel="stylesheet" type="text/css" href="assets/css/phppot-style.css" /> <script src="vendor/jquery/jquery-3.2.1.min.js"></script> </head> <body> <div class="phppot-container"> <h1>PHP contact form with captcha images</h1> <form name="frmContact" id="captcha-cnt-frm" class="phppot-form" frmContact"" method="post" action="" enctype="multipart/form-data" onsubmit="return validateContactForm()"> <div class="phppot-row"> <div class="label"> Name <span id="userName-info" class="validation-message"></span> </div> <input type="text" class="phppot-input" name="userName" id="userName" value="<?php if(!empty($_POST['userName'])&& $type == 'error'){ echo $_POST['userName'];}?>" /> </div> <div class="phppot-row"> <div class="label"> Email <span id="userEmail-info" class="validation-message"></span> </div> <input type="text" class="phppot-input" name="userEmail" id="userEmail" value="<?php if(!empty($_POST['userEmail'])&& $type == 'error'){ echo $_POST['userEmail'];}?>" /> </div> <div class="phppot-row"> <div class="label"> Subject <span id="subject-info" class="validation-message"></span> </div> <input type="text" class="phppot-input" name="subject" id="subject" value="<?php if(!empty($_POST['subject'])&& $type == 'error'){ echo $_POST['subject'];}?>" /> </div> <div class="phppot-row"> <div class="label"> Message <span id="userMessage-info" class="validation-message"></span> </div> <textarea name="content" id="content" class="phppot-input" cols="60" rows="6"><?php if(!empty($_POST['content'])&& $type == 'error'){ echo $_POST['content'];}?></textarea> </div> <?php if (! empty($result)) { ?> <div class="phppot-row"> <div class="captcha-container <?php if(!empty($border)){ echo $border;} ?>"> <p> Select the <span class="text-color"><?php echo $result[0]['name'];?> </span><span id="captcha-info" class="validation-message"></span> </p> <input type="hidden" name="captcha_code" value="<?php echo $result[0]['name'];?>"> <?php shuffle($captchaOutput); if (! empty($captchaOutput)) { foreach ($captchaOutput as $value) { ?> <div class="svg-padding"> <div class="svg"><?php echo $value['captcha_icon'];?> <input type="hidden" class="icons" value="<?php echo $value['name'];?>"> </div> </div> <?php }}?> </div> </div> <?php }?> <div class="phppot-row"> <input type="submit" name="send" class="send-button" value="Send" /> </div> <input type="hidden" name="captcha_chosen" id="captcha-chosen" value=""> </form> <?php if(!empty($message)) { ?> <div id="phppot-message" class="<?php echo $type; ?>"><?php if(isset($message)){ ?> <?php echo $message; }}?> </div> </div> <script src="assets/js/captcha.js"></script> </body> </html>

jQuery script to validate contact form and highlight captcha selection

This section shows the jQuery script for validation and captcha selection.

The validateContactForm() function is handling the form validation. All the contact form fields are mandatory. This function is making sure about the non-empty state of the form fields.

On selecting one of the lists of captcha images, the script puts the selected value in a form field. Also, it highlights the selected by adding CSS via script.

If the user selects no captcha, then the validation will return false.

assets/js/captcha.js

function validateContactForm() { var valid = true; $("#userName").removeClass("error-field"); $("#userEmail").removeClass("error-field"); $("#subject").removeClass("error-field"); $("#content").removeClass("error-field"); $("#userName-info").html("").hide(); $("#userEmail-info").html("").hide(); $("#subject-info").html("").hide(); $("#content-info").html("").hide(); $(".validation-message").html(""); $(".phppot-input").css('border', '#e0dfdf 1px solid'); $(".captcha-container").css('border', '#e0dfdf 1px solid'); var userName = $("#userName").val(); var userEmail = $("#userEmail").val(); var subject = $("#subject").val(); var content = $("#content").val(); var captcha = $("#captcha-chosen").val(); if (userName.trim() == "") { $("#userName-info").html("required.").css("color", "#ee0000").show(); $("#userName").css('border', '#e66262 1px solid'); $("#userName").addClass("error-field"); valid = false; } if (userEmail.trim() == "") { $("#userEmail-info").html("required.").css("color", "#ee0000").show(); $("#userEmail").css('border', '#e66262 1px solid'); $("#userEmail").addClass("error-field"); valid = false; } if (!userEmail.match(/^([\w-\.]+@([\w-]+\.)+[\w-]{2,4})?$/)) { $("#userEmail-info").html("invalid email address.").css("color", "#ee0000").show(); $("#userEmail").css('border', '#e66262 1px solid'); $("#userEmail").addClass("error-field"); valid = false; } if (subject == "") { $("#subject-info").html("required.").css("color", "#ee0000").show(); $("#subject").css('border', '#e66262 1px solid'); $("#subject").addClass("error-field"); valid = false; } if (content == "") { $("#userMessage-info").html("required.").css("color", "#ee0000").show(); $("#content").css('border', '#e66262 1px solid'); $("#content").addClass("error-field"); valid = false; } if (captcha == "") { $("#captcha-info").html("required."); $(".captcha-container").css('border', '#e66262 1px solid'); valid = false; } if (valid == false) { $('.error-field').first().focus(); valid = false; } return valid; } $(".svg-padding").on('click', function() { $(".svg").removeClass('captcha-selected'); $(this).find(".svg").addClass('captcha-selected'); var icons = $(this).find(".icons").val(); $("#captcha-chosen").val(icons); });

CSS created for contact form example

These are the exclusive styles created to present the contact form. Mostly, it contains styles for the captcha section.

I used a generic CSS template for designing other common form components. You can find this CSS in the downloadable.

assets/css/contact-form-style.css

.svg-padding { display: inline-block; } .svg { cursor: pointer; padding: 5px 5px 5px 5px; border-radius: 3px; margin: 0px 5px 0px 5px; border: 1px solid #FFF; } .text-color { font-weight: bold; } .captcha-container { background: #fff; padding: 15px; border: 1px solid #9a9a9a; width: 270px; border-radius: 3px; padding-top: 0px; } .error-field { border: 1px solid #d96557; } .send-button { cursor: pointer; background: #3cb73c; border: #36a536 1px solid; color: #FFF; font-size: 1em; width: 100px; } .captcha-selected { color: #1cb87b; background-color: #e3e3e3; border: #d7d7d7 1px solid; } .border-error-color { border: 1px solid #e66262; }

On loading the contact form, the PHP code reads the random captcha images from the database. In PHP, it picks one image from the random results as the captcha code.

The HTML form contains a hidden field to have this code.

When the user selects an image and posts it to the PHP, it will validate the selected captcha.

The user-selected captcha is matched with the pre-loaded code, then the PHP code will return true. Then, it will process the contact email sending script.

index.php (Captcha Validation and Mail sending)

<?php namespace Phppot; require_once ("Model/Contact.php"); $contact = new Contact(); if (! empty($_POST['send'])) { if ($_POST['captcha_code'] == $_POST['captcha_chosen']) { $contact->sendContactMail($_POST); $message = "Hi, we have received your message. Thank you."; $type = "success"; } else { $message = "Invalid captcha. Please select the correct image."; $type = "error"; $border = "border-error-color"; } } $result = $contact->getRecord(); $termId = $result[0]['id']; $captchaResult = $contact->getCaptchaIcons($termId); $randomCaptchaResult = $contact->getRandomCaptchaId($termId); $captchaOutput = array_merge($captchaResult, $randomCaptchaResult); ?>

In this PHP model class, it has the functions to read random captcha images from the database.

The getRecord() method reads a single random record to load captcha code on the page load.

The sendContactMail() function send the contact mail. I used PHP mail() function for this example. If you want to use SMTP for sending the email, you can see the example in the linked article.

Model/Contact.php

<?php namespace Phppot; use Phppot\DataSource; class Contact { private $ds; function __construct() { require_once __DIR__ . './../lib/DataSource.php'; $this->ds = new DataSource(); } function getRecord() { $query = "SELECT * FROM tbl_term ORDER BY RAND() LIMIT 1"; $result = $this->ds->select($query); return $result; } function getCaptchaIcons($id) { $query = "SELECT tbl_captcha_images.*, tbl_term.name FROM tbl_captcha_images JOIN tbl_term ON tbl_captcha_images.term_id = tbl_term.id WHERE term_id != " . $id . " ORDER BY RAND() LIMIT 4"; $captchaResult = $this->ds->select($query); return $captchaResult; } function getRandomCaptchaId($id) { $query = "SELECT tbl_captcha_images.*, tbl_term.name FROM tbl_captcha_images JOIN tbl_term ON tbl_captcha_images.term_id = tbl_term.id WHERE term_id = " . $id . " ORDER BY RAND() LIMIT 1"; $captcha = $this->ds->select($query); return $captcha; } function sendContactMail($postValues) { $name = $postValues["userName"]; $email = $postValues["userEmail"]; $subject = $postValues["subject"]; $content = $postValues["content"]; $toEmail = "SITE_ADMIN_EMAIL"; // Put in place the recipient email $mailHeaders = "From: " . $name . "<" . $email . ">\r\n"; mail($toEmail, $subject, $content, $mailHeaders); } }

lib/Datasource.php

<?php namespace Phppot; /** * Generic datasource class for handling DB operations. * Uses MySqli and PreparedStatements. * * @version 2.3 */ class DataSource { // PHP 7.1.0 visibility modifiers are allowed for class constants. // when using above 7.1.0, declare the below constants as private const HOST = 'localhost'; const USERNAME = 'root'; const PASSWORD = ''; const DATABASENAME = 'contact_form_captcha'; private $conn; /** * PHP implicitly takes care of cleanup for default connection types. * So no need to worry about closing the connection. * * Singletons not required in PHP as there is no * concept of shared memory. * Every object lives only for a request. * * Keeping things simple and that works! */ function __construct() { $this->conn = $this->getConnection(); } /** * If connection object is needed use this method and get access to it. * Otherwise, use the below methods for insert / update / etc. * * @return \mysqli */ public function getConnection() { $conn = new \mysqli(self::HOST, self::USERNAME, self::PASSWORD, self::DATABASENAME); if (mysqli_connect_errno()) { trigger_error("Problem with connecting to database."); } $conn->set_charset("utf8"); return $conn; } /** * To get database results * * @param string $query * @param string $paramType * @param array $paramArray * @return array */ public function select($query, $paramType = "", $paramArray = array()) { $stmt = $this->conn->prepare($query); if (! empty($paramType) && ! empty($paramArray)) { $this->bindQueryParams($stmt, $paramType, $paramArray); } $stmt->execute(); $result = $stmt->get_result(); if ($result->num_rows > 0) { while ($row = $result->fetch_assoc()) { $resultset[] = $row; } } if (! empty($resultset)) { return $resultset; } } }

This SQL script includes the structure and data of the tables used to display custom captcha. The tbl_captcha_images table contains the SVG markup of the captcha images.

I have used another table tbl_term to hold the captcha term and title. The captcha term is for stating the user what to select. The captcha title is a slug to add it with a title attribute.

sql/contact_form_captcha.sql

-- -- Database: `contact_form_captcha` -- -- -------------------------------------------------------- -- -- Table structure for table `tbl_captcha_images` -- CREATE TABLE `tbl_captcha_images` ( `id` int(11) NOT NULL, `term_id` int(11) NOT NULL, `captcha_icon` text NOT NULL ) ENGINE=InnoDB DEFAULT CHARSET=latin1; -- -- Dumping data for table `tbl_captcha_images` -- INSERT INTO `tbl_captcha_images` (`id`, `term_id`, `captcha_icon`) VALUES (1, 1, '<svg width=\"25px\" height=\"25px\" aria-hidden=\"true\" role=\"img\" xmlns=\"http://www.w3.org/2000/svg\" viewBox=\"0 0 640 512\"><path fill=\"currentColor\" d=\"M192 384h192c53 0 96-43 96-96h32c70.6 0 128-57.4 128-128S582.6 32 512 32H120c-13.3 0-24 10.7-24 24v232c0 53 43 96 96 96zM512 96c35.3 0 64 28.7 64 64s-28.7 64-64 64h-32V96h32zm47.7 384H48.3c-47.6 0-61-64-36-64h583.3c25 0 11.8 64-35.9 64z\"></path></svg>'), (2, 2, '<svg width=\"25px\" height=\"25px\" aria-hidden=\"true\" role=\"img\" xmlns=\"http://www.w3.org/2000/svg\" viewBox=\"0 0 576 512\"><path fill=\"currentColor\" d=\"M259.3 17.8L194 150.2 47.9 171.5c-26.2 3.8-36.7 36.1-17.7 54.6l105.7 103-25 145.5c-4.5 26.3 23.2 46 46.4 33.7L288 439.6l130.7 68.7c23.2 12.2 50.9-7.4 46.4-33.7l-25-145.5 105.7-103c19-18.5 8.5-50.8-17.7-54.6L382 150.2 316.7 17.8c-11.7-23.6-45.6-23.9-57.4 0z\"></path></svg>'), (3, 3, '<svg width=\"25px\" height=\"25px\" aria-hidden=\"true\" role=\"img\" xmlns=\"http://www.w3.org/2000/svg\" viewBox=\"0 0 384 512\"><path fill=\"currentColor\" d=\"M377.33 375.429L293.906 288H328c21.017 0 31.872-25.207 17.448-40.479L262.79 160H296c20.878 0 31.851-24.969 17.587-40.331l-104-112.003c-9.485-10.214-25.676-10.229-35.174 0l-104 112.003C56.206 134.969 67.037 160 88 160h33.21l-82.659 87.521C24.121 262.801 34.993 288 56 288h34.094L6.665 375.429C-7.869 390.655 2.925 416 24.025 416H144c0 32.781-11.188 49.26-33.995 67.506C98.225 492.93 104.914 512 120 512h144c15.086 0 21.776-19.069 9.995-28.494-19.768-15.814-33.992-31.665-33.995-67.496V416h119.97c21.05 0 31.929-25.309 17.36-40.571z\"></path></svg>'), (4, 4, '<svg width=\"25px\" height=\"25px\" aria-hidden=\"true\" role=\"img\" xmlns=\"http://www.w3.org/2000/svg\" viewBox=\"0 0 640 512\"><path fill=\"currentColor\" d=\"M624 352h-16V243.9c0-12.7-5.1-24.9-14.1-33.9L494 110.1c-9-9-21.2-14.1-33.9-14.1H416V48c0-26.5-21.5-48-48-48H48C21.5 0 0 21.5 0 48v320c0 26.5 21.5 48 48 48h16c0 53 43 96 96 96s96-43 96-96h128c0 53 43 96 96 96s96-43 96-96h48c8.8 0 16-7.2 16-16v-32c0-8.8-7.2-16-16-16zM160 464c-26.5 0-48-21.5-48-48s21.5-48 48-48 48 21.5 48 48-21.5 48-48 48zm320 0c-26.5 0-48-21.5-48-48s21.5-48 48-48 48 21.5 48 48-21.5 48-48 48zm80-208H416V144h44.1l99.9 99.9V256z\"></path></svg>'), (5, 5, '<svg width=\"25px\" height=\"25px\" aria-hidden=\"true\" role=\"img\" xmlns=\"http://www.w3.org/2000/svg\" viewBox=\"0 0 512 512\"><path fill=\"currentColor\" d=\"M512 176.001C512 273.203 433.202 352 336 352c-11.22 0-22.19-1.062-32.827-3.069l-24.012 27.014A23.999 23.999 0 0 1 261.223 384H224v40c0 13.255-10.745 24-24 24h-40v40c0 13.255-10.745 24-24 24H24c-13.255 0-24-10.745-24-24v-78.059c0-6.365 2.529-12.47 7.029-16.971l161.802-161.802C163.108 213.814 160 195.271 160 176 160 78.798 238.797.001 335.999 0 433.488-.001 512 78.511 512 176.001zM336 128c0 26.51 21.49 48 48 48s48-21.49 48-48-21.49-48-48-48-48 21.49-48 48z\"></path></svg>'), (6, 6, '<svg width=\"25px\" height=\"25px\" aria-hidden=\"true\" role=\"img\" xmlns=\"http://www.w3.org/2000/svg\" viewBox=\"0 0 512 512\"><path fill=\"currentColor\" d=\"M499.991 168h-54.815l-7.854-20.944c-9.192-24.513-25.425-45.351-46.942-60.263S343.651 64 317.472 64H194.528c-26.18 0-51.391 7.882-72.908 22.793-21.518 14.912-37.75 35.75-46.942 60.263L66.824 168H12.009c-8.191 0-13.974 8.024-11.384 15.795l8 24A12 12 0 0 0 20.009 216h28.815l-.052.14C29.222 227.093 16 247.997 16 272v48c0 16.225 6.049 31.029 16 42.309V424c0 13.255 10.745 24 24 24h48c13.255 0 24-10.745 24-24v-40h256v40c0 13.255 10.745 24 24 24h48c13.255 0 24-10.745 24-24v-61.691c9.951-11.281 16-26.085 16-42.309v-48c0-24.003-13.222-44.907-32.772-55.86l-.052-.14h28.815a12 12 0 0 0 11.384-8.205l8-24c2.59-7.771-3.193-15.795-11.384-15.795zm-365.388 1.528C143.918 144.689 168 128 194.528 128h122.944c26.528 0 50.61 16.689 59.925 41.528L391.824 208H120.176l14.427-38.472zM88 328c-17.673 0-32-14.327-32-32 0-17.673 14.327-32 32-32s48 30.327 48 48-30.327 16-48 16zm336 0c-17.673 0-48 1.673-48-16 0-17.673 30.327-48 48-48s32 14.327 32 32c0 17.673-14.327 32-32 32z\"></path></svg>'), (7, 7, '<svg width=\"25px\" height=\"25px\" aria-hidden=\"true\" role=\"img\" xmlns=\"http://www.w3.org/2000/svg\" viewBox=\"0 0 576 512\"><path fill=\"currentColor\" d=\"M414.9 24C361.8 24 312 65.7 288 89.3 264 65.7 214.2 24 161.1 24 70.3 24 16 76.9 16 165.5c0 72.6 66.8 133.3 69.2 135.4l187 180.8c8.8 8.5 22.8 8.5 31.6 0l186.7-180.2c2.7-2.7 69.5-63.5 69.5-136C560 76.9 505.7 24 414.9 24z\"></path></svg>'), (8, 8, '<svg width=\"25px\" height=\"25px\" aria-hidden=\"true\" role=\"img\" xmlns=\"http://www.w3.org/2000/svg\" viewBox=\"0 0 576 512\"><path fill=\"currentColor\" d=\"M488 312.7V456c0 13.3-10.7 24-24 24H348c-6.6 0-12-5.4-12-12V356c0-6.6-5.4-12-12-12h-72c-6.6 0-12 5.4-12 12v112c0 6.6-5.4 12-12 12H112c-13.3 0-24-10.7-24-24V312.7c0-3.6 1.6-7 4.4-9.3l188-154.8c4.4-3.6 10.8-3.6 15.3 0l188 154.8c2.7 2.3 4.3 5.7 4.3 9.3zm83.6-60.9L488 182.9V44.4c0-6.6-5.4-12-12-12h-56c-6.6 0-12 5.4-12 12V117l-89.5-73.7c-17.7-14.6-43.3-14.6-61 0L4.4 251.8c-5.1 4.2-5.8 11.8-1.6 16.9l25.5 31c4.2 5.1 11.8 5.8 16.9 1.6l235.2-193.7c4.4-3.6 10.8-3.6 15.3 0l235.2 193.7c5.1 4.2 12.7 3.5 16.9-1.6l25.5-31c4.2-5.2 3.4-12.7-1.7-16.9z\"></path></svg>'), (9, 9, '<svg width=\"25px\" height=\"25px\" aria-hidden=\"true\" role=\"img\" xmlns=\"http://www.w3.org/2000/svg\" viewBox=\"0 0 512 512\"><path fill=\"currentColor\" d=\"M349.565 98.783C295.978 98.783 251.721 64 184.348 64c-24.955 0-47.309 4.384-68.045 12.013a55.947 55.947 0 0 0 3.586-23.562C118.117 24.015 94.806 1.206 66.338.048 34.345-1.254 8 24.296 8 56c0 19.026 9.497 35.825 24 45.945V488c0 13.255 10.745 24 24 24h16c13.255 0 24-10.745 24-24v-94.4c28.311-12.064 63.582-22.122 114.435-22.122 53.588 0 97.844 34.783 165.217 34.783 48.169 0 86.667-16.294 122.505-40.858C506.84 359.452 512 349.571 512 339.045v-243.1c0-23.393-24.269-38.87-45.485-29.016-34.338 15.948-76.454 31.854-116.95 31.854z\"></path></svg>'), (10, 10, '<svg width=\"25px\" height=\"25px\" aria-hidden=\"true\" role=\"img\" xmlns=\"http://www.w3.org/2000/svg\" viewBox=\"0 0 576 512\"><path fill=\"currentColor\" d=\"M472 200H360.211L256.013 5.711A12 12 0 0 0 245.793 0h-57.787c-7.85 0-13.586 7.413-11.616 15.011L209.624 200H99.766l-34.904-58.174A12 12 0 0 0 54.572 136H12.004c-7.572 0-13.252 6.928-11.767 14.353l21.129 105.648L.237 361.646c-1.485 7.426 4.195 14.354 11.768 14.353l42.568-.002c4.215 0 8.121-2.212 10.289-5.826L99.766 312h109.858L176.39 496.989c-1.97 7.599 3.766 15.011 11.616 15.011h57.787a12 12 0 0 0 10.22-5.711L360.212 312H472c57.438 0 104-25.072 104-56s-46.562-56-104-56z\"></path></svg>'); -- -------------------------------------------------------- -- -- Table structure for table `tbl_term` -- CREATE TABLE `tbl_term` ( `id` int(11) NOT NULL, `name` varchar(255) NOT NULL, `slug` varchar(255) NOT NULL ) ENGINE=InnoDB DEFAULT CHARSET=latin1; -- -- Dumping data for table `tbl_term` -- INSERT INTO `tbl_term` (`id`, `name`, `slug`) VALUES (1, 'cup', 'cup-1'), (2, 'star', 'star-2'), (3, 'tree', 'tree-3'), (4, 'truck', 'truck-4'), (5, 'key', 'key-5'), (6, 'car', 'car-6'), (7, 'heart', 'heart-7'), (8, 'house', 'house-8'), (9, 'flag', 'flag-9'), (10, 'plane', 'plane-10'); -- -- Indexes for dumped tables -- -- -- Indexes for table `tbl_captcha_images` -- ALTER TABLE `tbl_captcha_images` ADD PRIMARY KEY (`id`); -- -- Indexes for table `tbl_term` -- ALTER TABLE `tbl_term` ADD PRIMARY KEY (`id`); -- -- AUTO_INCREMENT for dumped tables -- -- -- AUTO_INCREMENT for table `tbl_captcha_images` -- ALTER TABLE `tbl_captcha_images` MODIFY `id` int(11) NOT NULL AUTO_INCREMENT, AUTO_INCREMENT=11; -- -- AUTO_INCREMENT for table `tbl_term` -- ALTER TABLE `tbl_term` MODIFY `id` int(11) NOT NULL AUTO_INCREMENT, AUTO_INCREMENT=11; COMMIT;

This screenshot shows the output of this PHP contact form example. It displays the custom image captcha in the form.

It focuses on the captcha section because of the form submitted with invalid captcha.

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Posted on January 7, 2020 by sick skills — Leave a comment

Python Regex Flags

In many functions, you see a third argument flags. What are they and how do they work?

Flags allow you to control the regular expression engine. Because regular expressions are so powerful, they are a useful way of switching on and off certain features (e.g. whether to ignore capitalization when matching your regex).

For example, here’s how the third argument flags is used in the re.findall() method:

re.findall(pattern, string, flags=0)

So the flags argument seems to be an integer argument with the default value of 0. To control the default regex behavior, you simply use one of the predefined integer values. You can access these predefined values via the re library:

Syntax	Meaning
re.ASCII	If you don’t use this flag, the special Python regex symbols \w, \W, \b, \B, \d, \D, \s and \S will match Unicode characters. If you use this flag, those special symbols will match only ASCII characters — as the name suggests.
re.A	Same as re.ASCII
re.DEBUG	If you use this flag, Python will print some useful information to the shell that helps you debugging your regex.
re.IGNORECASE	If you use this flag, the regex engine will perform case-insensitive matching. So if you’re searching for [A-Z], it will also match [a-z].
re.I	Same as re.IGNORECASE
re.LOCALE	Don’t use this flag — ever. It’s depreciated—the idea was to perform case-insensitive matching depending on your current locale. But it isn’t reliable.
re.L	Same as re.LOCALE
re.MULTILINE	This flag switches on the following feature: the start-of-the-string regex ‘^’ matches at the beginning of each line (rather than only at the beginning of the string). The same holds for the end-of-the-string regex ‘$’ that now matches also at the end of each line in a multi-line string.
re.M	Same as re.MULTILINE
re.DOTALL	Without using this flag, the dot regex ‘.’ matches all characters except the newline character ‘\n’. Switch on this flag to really match all characters including the newline character.
re.S	Same as re.DOTALL
re.VERBOSE	To improve the readability of complicated regular expressions, you may want to allow comments and (multi-line) formatting of the regex itself. This is possible with this flag: all whitespace characters and lines that start with the character ‘#’ are ignored in the regex.
re.X	Same as re.VERBOSE

How to Use These Flags?

Simply include the flag as the optional flag argument as follows:

import re text = ''' Ha! let me see her: out, alas! he's cold: Her blood is settled, and her joints are stiff; Life and these lips have long been separated: Death lies on her like an untimely frost Upon the sweetest flower of all the field. ''' print(re.findall('HER', text, flags=re.IGNORECASE))
# ['her', 'Her', 'her', 'her']

As you see, the re.IGNORECASE flag ensures that all occurrences of the string ‘her’ are matched—no matter their capitalization.

How to Use Multiple Flags?

Yes, simply add them together (sum them up) as follows:

import re text = ''' Ha! let me see her: out, alas! he's cold: Her blood is settled, and her joints are stiff; Life and these lips have long been separated: Death lies on her like an untimely frost Upon the sweetest flower of all the field. ''' print(re.findall(' HER # Ignored', text, flags=re.IGNORECASE + re.VERBOSE))
# ['her', 'Her', 'her', 'her']

You use both flags re.IGNORECASE (all occurrences of lower- or uppercase string variants of ‘her’ are matched) and re.VERBOSE (ignore comments and whitespaces in the regex). You sum them together re.IGNORECASE + re.VERBOSE to indicate that you want to take both.

What is inside?

What is Shipping API?

Capabilities of Shipping APIs

Existing shipping API available

About Australia Post API

About this example

File Structure

Australia Post shipping API integration steps

How to get the Australia Post PAC API key

Web interface to enter details to calculate shipping rates

CSS created to present the payment form

jQuery script to validate the shipping details

PHP code with Australia Post shipping API request-response handlers

Australia Post shipping API integration output

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