Tag: Using Software

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The pieces of Fedora Silverblue

Fedora Silverblue provides a useful workstation build on an immutable operating system. In “What is Silverblue?“, you learned about the benefits that an immutable OS provides. But what pieces go into making it? This article examines some of the technology that powers Silverblue.

The filesystem

Fedora Workstation users may find the idea of an immutable OS to be the most brain-melting part of Silverblue. What does that mean? Find some answers by taking a look at the filesystem.

At first glance, the layout looks pretty much the same as a regular Fedora file system. It has some differences, like making /home a symbolic link to /var/home. And you can get more answers by looking at how libostree works. libostree treats the whole tree like it’s an object, checks it into a code repository, and checks out a copy for your machine to use.

libostree

The libostree project supplies the goods for managing Silverblue’s file system. It is an upgrade system that the user can control using rpm-ostree commands.

libostree knows nothing about packages—an upgrade means replacing one complete file system with another complete file system. libostree treats the file system tree as one atomic object (an unbreakable unit). In fact, the forerunner to Silverblue was named Project Atomic.

The libostree project provides a library and set of tools. It’s an upgrade system that carries out these tasks.

  1. Pull in a new file system
  2. Store the new file system
  3. Deploy the new file system

Pull in a new file system

Pulling in a new file system means copying an object (the entire file system) from a remote source to its own store. If you’ve worked with virtual machine image files, you already understand the concept of a file system object that you can copy.

Store the new file system

The libostree store has some source code control qualities—it stores many file system objects, and checks one out to be used as the root file system. libostree’s store has two parts:

  • a repository database at /sysroot/ostree/repo/
  • file systems in /sysroot/ostree/deploy/fedora/deploy/

libostree keeps track of what’s been checked in using commit IDs. Each commit ID can be found in a directory name, nested deep inside /sysroot .A libostree commit ID is a long checksum, and looks similar to a git commit ID.

$ ls -d /sysroot/ostree/deploy/fedora/deploy/*/
/sysroot/ostree/deploy/fedora/deploy/c4bf7a6339e6be97d0ca48a117a1a35c9c5e3256ae2db9e706b0147c5845fac4.0/

rpm-ostree status gives a little more information about that commit ID. The output is a little confusing; it can take a while to see this file system is Fedora 31.

$ rpm-ostree status
State: idle
AutomaticUpdates: disabled
Deployments:
● ostree://fedora:fedora/31/x86_64/silverblue Version: 31.1.9 (2019-10-23T21:44:48Z) Commit: c4bf7a6339e6be97d0ca48a117a1a35c9c5e3256ae2db9e706b0147c5845fac4 GPGSignature: Valid signature by 7D22D5867F2A4236474BF7B850CB390B3C3359C4

Deploy the new filesystem

libostree deploys a new file system by checking out the new object from its store. libostree doesn’t check out a file system by copying all the files—it uses hard links instead. If you look inside the commit ID directory, you see something that looks suspiciously like the root directory. That’s because it is the root directory. You can see these two directories are pointing to the same place by checking their inodes.

$ ls -di1 / /sysroot/ostree/deploy/fedora/deploy/*/
260102 /
260102 /sysroot/ostree/deploy/fedora/deploy/c4bf7a6339e6be97d0ca48a117a1a35c9c5e3256ae2db9e706b0147c5845fac4.0/

This is a fresh install, so there’s only one commit ID. After a system update, there will be two. If more copies of the file system are checked into libostree’s repo, more commit IDs appear here.

Upgrade process

Putting the pieces together, the update process looks like this:

  1. libostree checks out a copy of the file system object from the repository
  2. DNF installs packages into the copy
  3. libostree checks in the copy as a new object
  4. libostree checks out the copy to become the new file system
  5. You reboot to pick up the new system files

In addition to more safety, there is more flexibility. You can do new things with libostree’s repo, like store a few different file systems and check out whichever one you feel like using.

Silverblue’s root file system

Fedora keeps its system files in all the usual Linux places, such as /boot for boot files, /etc for configuration files, and /home for user home directories. The root directory in Silverblue looks much like the root directory in traditional Fedora, but there are some differences.

  • The filesystem has been checked out by libostree
  • Some directories are now symbolic links to new locations. For example, /home is a symbolic link to /var/home
  • /usr is a read-only directory
  • There’s a new directory named /sysroot. This is libostree’s new home

Juggling file systems

You can store many file systems and switch between them. This is called rebasing, and it’s similar to git rebasing. In fact, upgrading Silverblue to the next Fedora version is not a big package install—it’s a pull from a remote repository and a rebase.

You could store three copies with three different desktops: one KDE, one GNOME, and one XFCE. Or three different OS versions: how about keeping the current version, the nightly build, and an old classic? Switching between them is a matter of rebasing to the appropriate file system object.

Rebasing is also how you upgrade from one Fedora release to the next. See “How to rebase to Fedora 32 on Silverblue” for more information.

Flatpak

The Flatpak project provides a way of installing applications like LibreOffice. Applications are pulled from remote repositories like Flathub. It’s a kind of package manager, although you won’t find the word package in the docs. Traditional Fedora variants like Fedora Workstation can also use Flatpak, but the sandboxed nature of flatpaks make it particularly good for Silverblue. This way you do not have to do the entire ostree update process every time you wish to install an application.

Flatpak is well-suited to desktop applications, but also works for command line applications. You can install the vim editor with the command flatpak install flathub org.vim.Vim and run it with flatpak run org.vim.Vim.

toolbox

The toolbox project provides a traditional operating system inside a container. The idea is that you can mess with the mutable OS inside your toolbox (the Fedora container) as much as you like, and leave the immutable OS outside your toolbox untouched. You pack as many toolboxes as you want on your system, so you can keep work separated. Behind the scenes, the executable /usr/bin/toolbox is a shell script that uses podman.

A fresh install does not include a default toolbox. The toolbox create command checks the OS version (by reading /usr/lib/os-release), looks for a matching version at the Fedora container registry, and downloads the container.

$ toolbox create
Image required to create toolbox container.
Download registry.fedoraproject.org/f31/fedora-toolbox:31 (500MB)? [y/N]: y
Created container: fedora-toolbox-31
Enter with: toolbox enter

Hundreds of packages are installed inside the toolbox. The dnf command and the usual Fedora repos are set up, ready to install more. The ostree and rpm-ostree commands are not included – no immutable OS here.

Each user’s home directory is mounted on their toolbox, for storing content files outside the container.

Put the pieces together

Spend some time exploring Fedora Silverblue and it will become clear how these components fit together. Like other Fedora variants, all these of tools come from open source projects. You can get as up close and personal as you want, from reading their docs to contributing code. Or you can contribute to Silverblue itself.

Join the Fedora Silverblue conversations on discussion.fedoraproject.org or in #silverblue on Freenode IRC.

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4 cool new projects to try in COPR for May 2020

COPR is a collection of personal repositories for software that isn’t carried in Fedora. Some software doesn’t conform to standards that allow easy packaging. Or it may not meet other Fedora standards, despite being free and open source. COPR can offer these projects outside the Fedora set of packages. Software in COPR isn’t supported by Fedora infrastructure or signed by the project. However, it can be a neat way to try new or experimental software.

This article presents a few new and interesting projects in COPR. If you’re new to using COPR, see the COPR User Documentation for how to get started.

Ytop

Ytop is a command-line system monitor similar to htop. The main difference between them is that ytop, on top of showing processes and their CPU and memory usage, shows graphs of system CPU, memory, and network usage over time. Additionally, ytop shows disk usage and temperatures of the machine. Finally, ytop supports multiple color schemes as well as an option to create new ones.

Installation instructions

The repo currently provides ytop for Fedora 30, 31, 32, and Rawhide, as well as EPEL 7. To install ytop, use these commands with sudo:

sudo dnf copr enable atim/ytop
sudo dnf install ytop

Ctop

Ctop is yet another command-line system monitor. However, unlike htop and ytop, ctop focuses on showing resource usage of containers. Ctop shows both an overview of CPU, memory, network and disk usage of all containers running on your machine, and more comprehensive information about a single container, including graphs of resource usage over time. Currently, ctop has support for Docker and runc containers.

Installation instructions

The repo currently provides ctop for Fedora 31, 32 and Rawhide, EPEL 7, as well as for other distributions. To install ctop, use these commands:

sudo dnf copr enable fuhrmann/ctop
sudo dnf install ctop

Shortwave

Shortwave is a program for listening to radio stations. Shortwave uses a community database of radio stations www.radio-browser.info. In this database, you can discover or search for radio stations, add them to your library, and listen to them. Additionally, Shortwave provides information about currently playing song and can record the songs as well.

Installation instructions

The repo currently provides Shortwave for Fedora 31, 32, and Rawhide. To install Shortwave, use these commands:

sudo dnf copr enable atim/shortwave
sudo dnf install shortwave

Setzer

Setzer is a LaTeX editor that can build pdf documents and view them as well. It provides templates for various types of documents, such as articles or presentation slides. Additionally, Setzer has buttons for a lot of special symbols, math symbols and greek letters.

Installation instructions

The repo currently provides Setzer for Fedora 30, 31, 32, and Rawhide. To install Setzer, use these commands:

sudo dnf copr enable lyessaadi/setzer
sudo dnf install setzer
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How to contribute to Folding@home on Fedora

What is Folding@home?

Folding@home is a distributed computing network for performing biomedical research. Its intent is to help further understand and develop cures for a range of diseases. Their current priority is understanding the behavior of COVID-19 and the virus that causes COVID-19. This article will show you how you can get involved by donating your computer’s idle time.

Sounds cool, how do I help?

In order to donate your computational power to Folding@home, download the FAHClient package from this page. Once you’ve downloaded the package, open your Downloads folder and double click it to open. For instance, on standard Fedora Workstation, this opens GNOME Software, which prompts you to install the package.

Click install and enter your password to continue from here.

How to start Folding@home

Folding@home starts folding as soon as it is installed. In order to control how much CPU/GPU is using you must open the web control interface, available here.

The interface contains information about what project you are contributing to. In order to track “points,” the scoring system of Folding@home, you must set up a user account with Folding@home.

Tracking your work

Now that everything’s done, you may be wondering how you can track the work your computer is doing. All you need to is request a passkey from this page. Enter your email and your desired username. Once you have received the passkey in email, you can enter that into the client settings.

Click on the Change Identity button, and this page appears:

You can also put in a team number here like I have. This allows your points to go towards a group that you support.

Enter the username you gave when you requested a passkey, and then enter the passkey you received.

What next?

That’s all there is to it. Folding@home runs in the background automatically on startup. If you need to pause or lower how much CPU/GPU power it uses, you can change that via the web interface linked above.

You may notice that you don’t receive many work units. That’s because there is currently a shortage of work units to distribute due to a spike of computers being put onto the network. However, different efforts are emerging all the time.

You can visually see the spike in computers on the network from last year at the same time to 4/4/2020

Photo by Joshua Sortino on Unsplash.

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Using data from spreadsheets in Fedora with Python

Python is one of the most popular and powerful programming languages available. Because it’s free and open source, it’s available to everyone — and most Fedora systems come with the language already installed. Python is useful for a wide variety of tasks, but among them is processing comma-separated value (CSV) data. CSV files often start off life as tables or spreadsheets. This article shows how to get started working with CSV data in Python 3.

CSV data is precisely what it sounds like. A CSV file includes one row of data at a time, with data values separated by commas. Each row is defined by the same fields. Short CSV files are often easily read and understood. But longer data files, or those with more fields, may be harder to parse with the naked eye, so computers work better in those cases.

Here’s a simple example where the fields are Name, Email, and Country. In this example, the CSV data includes a field definition as the first row, although that is not always the case.

Name,Email,Country
John Q. Smith,jqsmith@example.com,USA
Petr Novak,pnovak@example.com,CZ
Bernard Jones,bjones@example.com,UK

Reading CSV from spreadsheets

Python helpfully includes a csv module that has functions for reading and writing CSV data. Most spreadsheet applications, both native like Excel or Numbers, and web-based such as Google Sheets, can export CSV data. In fact, many other services that can publish tabular reports will also export as CSV (PayPal for instance).

The Python csv module has a built in reader method called DictReader that can deal with each data row as an ordered dictionary (OrderedDict). It expects a file object to access the CSV data. So if our file above is called example.csv in the current directory, this code snippet is one way to get at this data:

f = open('example.csv', 'r')
from csv import DictReader
d = DictReader(f)
data = []
for row in d: data.append(row)

Now the data object in memory is a list of OrderedDict objects :

[OrderedDict([('Name', 'John Q. Smith'), ('Email', 'jqsmith@example.com'), ('Country', 'USA')]), OrderedDict([('Name', 'Petr Novak'), ('Email', 'pnovak@example.com'), ('Country', 'CZ')]), OrderedDict([('Name', 'Bernard Jones'), ('Email', 'bjones@example.com'), ('Country', 'UK')])]

Referencing each of these objects is easy:

>>> print(data[0]['Country'])
USA
>>> print(data[2]['Email'])
bjones@example.com

By the way, if you have to deal with a CSV file with no header row of field names, the DictReader class lets you define them. In the example above, add the fieldnames argument and pass a sequence of the names:

d = DictReader(f, fieldnames=['Name', 'Email', 'Country'])

A real world example

I recently wanted to pick a random winner from a long list of individuals. The CSV data I pulled from spreadsheets was a simple list of names and email addresses.

Fortunately, Python also has a helpful random module good for generating random values. The randrange function in the Random class from that module was just what I needed. You can give it a regular range of numbers — like integers — and a step value between them. The function then generates a random result, meaning I could get a random integer (or row number!) back within the total number of rows in my data.

So this small program worked well:

from csv import DictReader
from random import Random d = DictReader(open('mydata.csv'))
data = []
for row in d: data.append(row) r = Random()
winner = data[r.randrange(0, len(data), 1)]
print('The winner is:', winner['Name'])
print('Email address:', winner['Email'])

Obviously this example is extremely simple. Spreadsheets themselves include sophisticated ways to analyze data. However, if you want to do something outside the realm of your spreadsheet app, Python may be just the trick!

Photo by Isaac Smith on Unsplash.

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Control the firewall at the command line

A network firewall is more or less what it sounds like: a protective barrier that prevents unwanted network transmissions. They are most frequently used to prevent outsiders from contacting or using network services on a system. For instance, if you’re running a laptop at school or in a coffee shop, you probably don’t want strangers poking around on it.

Every Fedora system has a firewall built in. It’s part of the network functions in the Linux kernel inside. This article shows you how to change its settings using firewall-cmd.

Network basics

This article can’t teach you everything about computer networks. But a few basics suffice to get you started.

Any computer on a network has an IP address. Think of this just like a mailing address that allows correct routing of data. Each computer also has a set of ports, numbered 0-65535. These are not physical ports; instead, you can think of them as a set of connection points at the address.

In many cases, the port is a standard number or range depending on the application expected to answer. For instance, a web server typically reserves port 80 for non-secure HTTP communications, and/or 443 for secure HTTPS. The port numbers under 1024 are reserved for system and well-known purposes, ports 1024-49151 are registered, and ports 49152 and above are usually ephemeral (used only for a short time).

Each of the two most common protocols for Internet data transfer, TCP and UDP, have this set of ports. TCP is used when it’s important that all data be received and, if it arrives out of order, reassembled in the right order. UDP is used for more time-sensitive services that can withstand losing some data.

An application running on the system, such as a web server, reserves one or more ports (as seen above, 80 and 443 for example). Then during network communication, a host establishes a connection between a source address and port, and the destination address and port.

A network firewall can block or permit transmissions of network data based on rules like address, port, or other criteria. The firewall-cmd utility lets you interact with the rule set to view or change how the firewall works.

Firewall zones

To verify the firewall is running, use this command with sudo. (In fairness, you can run firewall-cmd without the sudo command in environments where PolicyKit is running.)

$ sudo firewall-cmd --state
running

The firewalld service supports any number of zones. Each zone can have its own settings and rules for protection. In addition, each network interface can be placed in any zone individually The default zone for an external facing interface (like the wifi or wired network card) on a Fedora Workstation is the FedoraWorkstation zone.

To see what zones are active, use the –get-active-zones flag. On this system, there are two network interfaces, a wired Ethernet card wlp2s0 and a virtualization (libvirt) bridge interface virbr0:

$ sudo firewall-cmd --get-active-zones
FedoraWorkstation interfaces: wlp2s0
libvirt interfaces: virbr0

To see the default zone, or all the defined zones:

$ sudo firewall-cmd --get-default-zone
FedoraWorkstation
$ sudo firewall-cmd --get-zones
FedoraServer FedoraWorkstation block dmz drop external home internal libvirt public trusted work

To see the services the firewall is allowing other systems to access in the default zone, use the –list-services flag. Here is an example from a customized system; you may see something different.

$ sudo firewall-cmd --list-services
dhcpv6-client mdns samba-client ssh

This system has four services exposed. Each of these has a well-known port number. The firewall recognizes them by name. For instance, the ssh service is associated with port 22.

To see other port settings for the firewall in the current zone, use the –list-ports flag. By the way, you can always declare the zone you want to check:

$ sudo firewall-cmd --list-ports --zone=FedoraWorkstation
1025-65535/udp 1025-65535/tcp

This shows that ports 1025 and above (both UDP and TCP) are open by default.

Changing zones, ports, and services

The above setting is a design decision.* It ensures novice users can use network facing applications they install. If you know what you’re doing and want a more protective default, you can move the interface to the FedoraServer zone, which prohibits any ports not explicitly allowed. (Warning: if you’re using the host via the network, you may break your connection — meaning you’ll have to go to that box physically to make further changes!)

$ sudo firewall-cmd --change-interface=<ifname> --zone=FedoraServer
success

* This article is not the place to discuss that decision, which went through many rounds of review and debate in the Fedora community. You are welcome to change settings as needed.

If you want to open a well-known port that belongs to a service, you can add that service to the default zone (or use –zone to adjust a different zone). You can add more than one at once. This example opens up the well-known ports for your web server for both HTTP and HTTPS traffic, on ports 80 and 443:

$ sudo firewall-cmd --add-service=http --add-service=https
success

Not all services are defined, but many are. To see the whole list, use the –get-services flag.

If you want to add specific ports, you can do that by number and protocol as well. (You can also combine –add-service and –add-port flags, as many as necessary.) This example opens up the UDP service for a network boot service:

$ sudo firewall-cmd --add-port=67/udp
success

Important: If you want your changes to be effective after you reboot your system or restart the firewalld service, you must add the –permanent flag to your commands. The examples here only change the firewall until one of those events next happens.

These are just some of the many functions of the firewall-cmd utility and the firewalld service. There is much more information on firewalld at the project’s home page that’s worth reading and trying out.

Photo by Jakob Braun on Unsplash.

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Connect your Google Drive to Fedora Workstation

There are plenty of cloud services available where you can store important documents. Google Drive is undoubtedly one of the most popular. It offers a matching set of applications like Docs, Sheets, and Slides to create content. But you can also store arbitrary content in your Google Drive. This article shows you how to connect it to your Fedora Workstation.

Adding an account

Fedora Workstation lets you add an account either after installation during first startup, or at any time afterward. To add your account during first startup, follow the prompts. Among them is a choice of accounts you can add:

Online account listing

Select Google and a login prompt appears for you to login, so use your Google account information.

Online account login dialog

Be aware this information is only transmitted to Google, not to the GNOME project. The next screen asks you to grant access, which is required so your system’s desktop can interact with Google. Scroll down to review the access requests, and choose Allow to proceed.

You can expect to receive notifications on mobile devices and Gmail that a new device — your system — accessed your Google account. This is normal and expected.

Online account access request dialog

If you didn’t do this at first startup, or you need to re-add your account, open the Settings tool, and select Online Accounts to add the account. The Settings tool is available through the dropdown at right side of the Top Bar (the “gear” icon), or by opening the Overview and typing settings. Then proceed as described above.

Using the Files app with Google Drive

Open the Files app (formerly known as nautilus). Locations the Files app can access appear on the left side. Locate your Google account in the list.

When you select this account, the Files app shows the contents of your Google drive. Some files can be opened using your Fedora Workstation local apps, such as sound files or LibreOffice-compatible files (including Microsoft Office docs). Other files, such as Google app files like Docs, Sheets, and Slides, open using your web browser and the corresponding app.

Remember that if the file is large, it will take some time to receive over the network so you can open it.

You can also copy and paste files in your Google Drive storage from or to other storage connected to your Fedora Workstation. You can also use the built in functions to rename files, create folders, and organize them.

Be aware that the Files app does not refresh contents in real time. If you add or remove files from other Google connected devices like your mobile phone or tablet, you may need to hit Ctrl+R to refresh the Files app view.

Photo by Beatriz Pérez Moya on Unsplash.

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Manage tasks and projects on Fedora with Taskwarrior

There are a multitude of applications to manage your todo list. One of these apps is Taskwarrior, it allows you to manage your task in the terminal without a GUI. This article will show you how to get started using it.

What is Taskwarrior?

Taskwarrior is CLI task manager and organizer. It is flexible, fast, and unobtrusive. It does its job then gets out of your way.

Taskwarrior uses $HOME/.taskrc and $HOME/.task to store your settings and tasks respectively.

Getting started with Taskwarrior

It’s easy to use the Taskwarrior to add your daily missions. These are some simple commands. To add tasks:

$ task add buy milk Created task 1. $ task add buy eggs Created task 2. $ task add bake cake Created task 3.

To list your tasks, you can use the task command on its own for the simplest listing:

$ task ID Age Description Urg 1 17s buy milk 0 2 14s buy eggs 0 3 11s bake cake 0 3 tasks.

To mark a task as complete, use the done keyword:

$ task 1 done Completed task 1 'buy milk'. Completed 1 task.
$ task 2 done Completed task 2 'buy eggs'. Completed 1 task.
$ task [task next] ID Age Description Urg 1 57s bake cake 0 1 task

Diving deeper into Taskwarrior

Priority management

Taskwarrior (task) is designed to help prioritize your tasks. To do this, task has multiple implicit and explicit variables it can use to determine an “Urgency” value.

Consider the following list.

$ task [task next] ID Age Description Urg 1 2min buy eggs 0 2 2min buy flour 0 3 2min bake cake 0 4 2min pay rent 0 5 3s install fedora 0 5 tasks

One could argue that paying your rent and installing Fedora have a higher priority than baking a cake. You can tell task about this by using the pri modifier. 

$ task 4 mod pri:H Modifying task 4 'pay rent'. Modified 1 task.
$ task 5 mod pri:M Modifying task 5 'install fedora'. Modified 1 task.
$ task [task next] ID Age P Description Urg  4 4min H pay rent 6
 5 2min M install fedora 3.9 1 4min buy eggs 0 2 4min buy flour 0 3 4min bake cake 0 5 tasks

Rent is very important, it has a due date that we need to pay it by, such as within 3 days from the 1st of the month. You can tell task this by using the due modifier. 

$ task 4 mod due:3rd Modifying task 4 'pay rent'. Modified 1 task.
$ task [task next] ID Age P Due Description Urg 4 12min H 2d pay rent 13.7 5 10min M install fedora 3.9 1 12min buy eggs 0 2 12min buy flour 0 3 12min bake cake 0 5 tasks
$ date Sat Feb 29 11:59:29 STD 2020

Because the 3rd of next month is nearby, the urgency value of rent has skyrocketed, and will continue to do so once we have reached and passed the due date.

However, not all tasks need to be done right away. Say for example you don’t want to worry about paying your rent until it is posted on the first of the month. You can tell taskwarrior about this using the wait modifier. (Hint: in the following example, som is short for “start of month,” one of the shortcuts taskwarrior understands.)

$ task 4 mod wait:som Modifying task 4 'pay rent'. Modified 1 task.
$ task [task next] ID Age P Description Urg 5 14min M install fedora 3.9 1 16min buy eggs 0 2 16min buy flour 0 3 16min bake cake 0 4 tasks

You will no longer be able to see the pay rent task until the start of the month. You can view waiting tasks by using task waiting:

$ task waiting ID Age P Wait Remaining Due Description 4 18min H 2020-03-01 11h 2020-03-03 pay rent 1 task

There are a few other modifiers you can define. Schedule and until will place a “start” date and remove a task after a date respectfully.

You may have tasks that require other tasks to be completed. To add a dependency for other tasks, use the dep modifier:

$ task [task next] ID Age P Description Urg 5 30min M install fedora 3.9 1 33min buy eggs 0 2 33min buy flour 0 3 33min bake cake 0 4 tasks
$ task 3 mod dep:1,2 Modifying task 3 'bake cake'. Modified 1 task. $ task [task next] ID Age Deps P Description Urg 1 33min buy eggs 8 2 33min buy flour 8 5 31min M install fedora 3.9 3 33min 1 2 bake cake -5 4 tasks

This will modify the priorities of any tasks that is blocking a task. Now buying eggs and flour is more urgent because it is preventing you from performing a task.

Annotations

You can add notes to a task using task <number> annotate: 

$ task 3 anno No blueberries Annotating task 3 'bake cake'. Annotated 1 task. $ task [task next] ID Age Deps P Description Urg 1 1h buy eggs 8 2 1h buy flour 8 5 1h M install fedora 3.9 3 1h 1 2 bake cake -4.2 2020-02-29 No blueberries 4 tasks

Organizing tasks

Tasks can being assigned to projects and tags by using the project modifier and adding a tag using the + sign followed by the tag name, such as +problem.

Putting it all together

You can combine everything you learned to create a task in one line with all the required options. 

$ task add Write Taskwarrior post \
pri:M due:1m wait:som until:due+2w sche:15th \
project:magazine +taskwarrior +community +linux Created task 6. The project 'magazine' has changed. Project 'magazine' is 0% complete (1 task remaining).
$ task 6 No command specified - assuming 'information'. Name Value ID 6 Description Write Taskwarrior post Status Waiting Project magazine Entered 2020-02-29 13:50:27 (6s) Waiting until 2020-03-01 00:00:00 Scheduled 2020-03-15 00:00:00 Due 2020-03-30 14:50:27 Until 2020-04-13 14:50:27 Last modified 2020-02-29 13:50:27 (6s) Tags taskwarrior community linux Virtual tags SCHEDULED TAGGED UDA UNBLOCKED UNTIL WAITING YEAR LATEST PROJECT PRIORITY UUID 27768737-f6a2-4515-af9d-4f58773c76a5 Urgency 5.3 Priority M

Installing Taskwarrior on Fedora

Taskwarrior is available in the default Fedora repository. To install it use this command with sudo:

$ sudo dnf install task

For rpm-ostree based distributions like Fedora Silverblue:

$ sudo rpm-ostree install task

Tips and tricks

  • Taskwarrior has a hook system, meaning that there are many tools you can plug in, such as bugwarrior!
  • Taskwarrior can connect to a taskserver for server/client setups. (This is left as an exercise for the reader for now.)

Photo by Bogdan Kupriets on Unsplash.

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Make free encrypted backups to the cloud on Fedora

Most free cloud storage is limited to 5GB or less. Even Google Drive is limited to 15GB. While not heavily advertised, IBM offers free accounts with a whopping 25GB of cloud storage for free. This is not a limited time offer, and you don’t have to provide a credit card. It’s absolutely free! Better yet, since it’s S3 compatible, most of the S3 tools available for backups should work fine.

This article will show you how to use restic for encrypted backups onto this free storage. Please also refer to this previous Magazine article about installing and configuring restic. Let’s get started!

Creating your free IBM account and storage

Head over to the IBM cloud services site and follow the steps to sign up for a free account here: https://cloud.ibm.com/registration. You’ll need to verify your account from the email confirmation that IBM sends to you.

Then log in to your account to bring up your dashboard, at https://cloud.ibm.com/.

Click on the Create resource button.

Click on Storage and then Object Storage.

Next click on the Create Bucket button.

This brings up the Configure your resource section.

Next, click on the Create button to use the default settings.

Under Predefined buckets click on the Standard box:

A unique bucket name is automatically created, but it’s suggested that you change this.

In this example, the bucket name is changed to freecloudstorage.

Click on the Next button after choosing a bucket name:

Continue to click on the Next button until you get the the Summary page:

Scroll down to the Endpoints section.

The information in the Public section is the location of your bucket. This is what you need to specify in restic when you create your backups. In this example, the location is s3.us-south.cloud-object-storage.appdomain.cloud.

Making your credentials

The last thing that you need to do is create an access ID and secret key. To start, click on Service credentials.

Click on the New credential button.

Choose a name for your credential, make sure you check the Include HMAC Credential box and then click on the Add button. In this example I’m using the name resticbackup.

Click on View credentials.

The access_key_id and secret_access_key is what you are looking for. (For obvious reasons, the author’s details here are obscured.)

You will need to export these by calling them with the export alias in the shell, or putting them into a backup script.

Preparing a new repository

Restic refers to your backup as a repository, and can make backups to any bucket on your IBM cloud account. First, setup the following environment variables using your access_key_id and secret_access_key that you retrieved from your IBM cloud bucket. These can also be set in any backup script you may create.

$ export AWS_ACCESS_KEY_ID=<MY_ACCESS_KEY>
$ export AWS_SECRET_ACCESS_KEY=<MY_SECRET_ACCESS_KEY>

Even though you are using IBM Cloud and not AWS, as previously mentioned, IBM Cloud storage is S3 compatible, and restic uses its interal AWS commands for any S3 compatible storage. So these AWS keys really refer to the keys from your IBM bucket.

Create the repository by initializing it. A prompt appears for you to type a password for the repository. Do not lose this password because your data is irrecoverable without it!

restic -r s3:http://PUBLIC_ENDPOINT_LOCATION/BUCKET init

The PUBLIC_ENDPOINT_LOCATION was specified in the Endpoint section of your Bucket summary.

For example:

$ restic -r s3:http://s3.us-south.cloud-object-storage.appdomain.cloud/freecloudstorage init

Creating backups

Now it’s time to backup some data. Backups are called snapshots. Run the following command and enter the repository password when prompted.

restic -r s3:http://PUBLIC_ENDPOINT_LOCATION/BUCKET backup files_to_backup

For example:

$ restic -r s3:http://s3.us-south.cloud-object-storage.appdomain.cloud/freecloudstorage backup Documents/
Enter password for repository: repository 106a2eb4 opened successfully, password is correct Files: 51 new, 0 changed, 0 unmodified Dirs: 0 new, 0 changed, 0 unmodified Added to the repo: 11.451 MiB processed 51 files, 11.451 MiB in 0:06 snapshot 611e9577 saved

Restoring from backups

Now that you’ve backed up some files, it’s time to make sure you know how to restore them. To get a list of all of your backup snapshots, use this command:

restic -r s3:http://PUBLIC_ENDPOINT_LOCATION/BUCKET snapshots

For example:

$ restic -r s3:http://s3.us-south.cloud-object-storage.appdomain.cloud/freecloudstorage snapshots
Enter password for repository: ID Date Host Tags Directory ------------------------------------------------------------------- 106a2eb4 2020-01-15 15:20:42 client /home/curt/Documents

To restore an entire snapshot, run a command like this:

restic -r s3:http://s3.us-south.cloud-object-storage.appdomain.cloud/freecloudstorage restore snapshotID --target restoreDirectory

For example:

$ restic -r s3:http://s3.us-south.cloud-object-storage.appdomain.cloud/freecloudstorage restore 106a2eb4 --target ~
Enter password for repository: repository 106a2eb4 opened successfully, password is correct
restoring <Snapshot 106a2eb4 of [/home/curt/Documents]

If the directory still exists on your system, be sure to specify a different location for the restoreDirectory. For example:

restic -r s3:http://s3.us-south.cloud-object-storage.appdomain.cloud/freecloudstorage restore 106a2eb4 --target /tmp

To restore an individual file, run a command like this:

restic -r s3:http://PUBLIC_ENDPOINT_LOCATION/BUCKET restore snapshotID --target restoreDirectory --include filename

For example:

$ restic -r s3:http://s3.us-south.cloud-object-storage.appdomain.cloud/freecloudstorage restore 106a2eb4 --target /tmp --include file1.txt Enter password for repository: restoring <Snapshot 106a2eb4 of [/home/curt/Documents] at 2020-01-16 15:20:42.833131988 -0400 EDT by curt@client> to /tmp

Photo by Alex Machado on Unsplash.

[EDITORS NOTE: The Fedora Project is sponsored by Red Hat, which is owned by IBM.]

[EDITORS NOTE: Updated at 1647 UTC on 24 February 2020 to correct a broken link.]

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Playing Music on your Fedora Terminal with MPD and ncmpcpp

MPD, as the name implies, is a Music Playing Daemon. It can play music but, being a daemon, any piece of software can interface with it and play sounds, including some CLI clients.

One of them is called ncmpcpp, which is an improvement over the pre-existing ncmpc tool. The name change doesn’t have much to do with the language they’re written in: they’re both C++, but ncmpcpp is called that because it’s the NCurses Music Playing Client Plus Plus.

Installing MPD and ncmpcpp

The ncmpmpcc client can be installed from the official Fedora repositories with DNF directly with

$ sudo dnf install ncmpcpp

On the other hand, MPD has to be installed from the RPMFusion free repositories, which you can enable, as per the official installation instructions, by running

$ sudo dnf install https://download1.rpmfusion.org/free/fedora/rpmfusion-free-release-$(rpm -E %fedora).noarch.rpm

and then you can install MPD by running

$ sudo dnf install mpd

Configuring and Starting MPD

The most painless way to set up MPD is to run it as a regular user. The default is to run it as the dedicated mpd user, but that causes all sorts of issues with permissions.

Before we can run it, we need to create a local config file that will allow it to run as a regular user.

To do that, create a subdirectory called mpd in ~/.config:

$ mkdir ~/.config/mpd

copy the default config file into this directory:

$ cp /etc/mpd.conf ~/.config/mpd

and then edit it with a text editor like vim, nano or gedit:

$ nano ~/.config/mpd/mpd.conf

I recommend you read through all of it to check if there’s anything you need to do, but for most setups you can delete everything and just leave the following:

db_file "~/.config/mpd/mpd.db" log_file "syslog"

At this point you should be able to just run

$ mpd

with no errors, which will start the MPD daemon in the background.

Using ncmpcpp

Simply run

$ ncmpcpp

and you’ll see a ncurses-powered graphical user interface in your terminal.

Press 4 and you should see your local music library, be able to change the selection using the arrow keys and press Enter to play a song.

Doing this multiple times will create a playlist, which allows you to move to the next track using the > button (not the right arrow, the > closing angle bracket character) and go back to the previous track with <. The + and – buttons increase and decrease volume. The Q button quits ncmpcpp but it doesn’t stop the music. You can play and pause with P.

You can see the current playlist by pressing the 1 button (this is the default view). From this view you can press i to look at the information (tags) about the current song. You can change the tags of the currently playing (or paused) song by pressing 6.

Pressing the \ button will add (or remove) an informative panel at the top of the view. In the top left, you should see something that looks like this:

[------]

Pressing the r, z, y, R, x buttons will respectively toggle the repeat, random, single, consume and crossfade playback modes and will replace one of the – characters in that little indicator to the initial of the selected mode.

Pressing the F1 button will display some help text, which contains a list of keybindings, so there’s no need to write a complete list here. So now go on, be geeky, and play all your music from your terminal!

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Connect Fedora to your Android phone with GSConnect

Both Apple and Microsoft offer varying levels of integration of their desktop offerings with your mobile devices. Fedora offers a similar if not greater degree of integration with GSConnect. It lets you pair your Android phone with your Fedora desktop and opens up a lot of possibilities. Keep reading to discover more about what it is and how it works.

What is GSConnect?

GSConnect is an implementation of the KDE Connect project tailored for the GNOME desktop. KDE Connect makes it possible for your devices to communicate with each other. However, installing it on Fedora’s default GNOME desktop requires pulling in a large number of KDE dependencies.

GSConnect is a complete implementation of KDE Connect, but in the form of a GNOME shell extension. Once installed, GSConnect lets you do the following and a lot more:

  • Receive phone notifications on your desktop and reply to messages
  • Use your phone as a remote control for your desktop
  • Share files and links between devices
  • Check your phone’s battery level from the desktop
  • Ring your phone to help find it

Setting up the GSConnect extension

Setting up GSConnect requires installing two components: the GSConnect extension on your desktop and the KDE Connect app on your Android device.

First, install the GSConnect extension from the GNOME Shell extensions website: GSConnect. (Fedora Magazine has a handy article on How to install a GNOME Shell extension to help you with this step.)

The KDE Connect app is available on Google’s Play Store. It’s also available on the FOSS Android apps repository, F-Droid.

Once you have installed both these components, you can pair your two devices. Installing the extension makes it show up in your system menu as Mobile Devices. Clicking on it displays a drop down menu, from which you can access Mobile Settings.

GSConnect menu within system menu

Here’s where you can view your paired devices and manage the features offered by GSConnect. Once you are on this screen, launch the app on your Android device.

You can initiate pairing from either device, but here you’ll be connecting to your desktop from the Android device. Simply hit refresh on the app, and as long as both devices are on the same wireless network, your desktop shows up in your Android device. You can now send a pair request to the desktop. Accept the pair request on your desktop to complete the pairing.

Pair request from Android app to desktop

Using GSConnect

Once paired, you’ll need to grant permissions on your Android device to make use of the many features available on GSConnect. Click on the paired device in the list of devices to see all available functions and enable or disable them according to your preferences.

GSConnect device preferences

Remember that you’ll also need to grant corresponding permissions in the Android app to be able to use these functions. Depending upon the features you’ve enabled and the permissions you’ve granted, you can now access your mobile contacts on your desktop, get notified of messages and reply to them, and even sync the desktop and Android device clipboards.

Integration with Files and your web browsers

GSConnect allows you to directly send files to your Android device from your desktop file explorer’s context menu.

On Fedora’s default GNOME desktop, you will need to install the nautilus-python package in order to make your paired devices show up in the context menu. Installing this is as straightforward as running the following command from your preferred terminal:

$ sudo dnf install nautilus-python

Once done, the Send to Mobile Device entry appears in the context menu of the Files app.

Context menu entry to send file to mobile device

Similarly, install the corresponding WebExtension for your browser, be it Firefox or Chrome, to send links to your Android device. You have the option to send the link to launch directly in your browser or to deliver it as SMS.

Running Commands

GSConnect lets you define commands which you can then run on your desktop, from your remote device. This allows you to do things such as take a screenshot of your desktop, or lock and unlock your desktop from your Android device, remotely.

Define commands to be run from the mobile device, on the desktop

To make use of this feature, you can use standard shell commands and the CLI exposed by GSConnect. Documentation on this is provided in the project’s GitHub repository: CLI Scripting.

The KDE UserBase Wiki has a list of example commands. These examples cover controlling the brightness and volume on your desktop, locking the mouse and keyboard, and even changing the desktop theme. Some of the commands are specific for KDE Plasma, and modifications are necessary to make it run on the GNOME desktop.

Explore and have fun

GSConnect makes it possible to enjoy a great degree of convenience and comfort. Dive into the preferences to see all that you can do and get creative with the commands function. Feel free to share all the possibilities this utility unlocked in your workflow in the comments below.

Photo by Pathum Danthanarayana on Unsplash.