Tag: Development

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PHP Development on Fedora with Eclipse

Eclipse is a full-featured free and open source IDE developed by the Eclipse Foundation. It has been around since 2001. You can write anything from C/C++ and Java to PHP, Python, HTML, JavaScript, Kotlin, and more in this IDE.

Installation

The software is available from Fedora’s official repository. To install it, invoke: 

sudo dnf install eclipse

This will install the base IDE and Eclipse platform, which enables you to develop Java applications. In order to add PHP development support to the IDE, run this command: 

sudo dnf install eclipse-pdt

This will install PHP development tools like PHP project wizard, PHP server configurations, composer support, etc.

Features

This IDE has many features that make PHP development easier. For example, it has a comprehensive project wizard (where you can configure many options for your new projects). It also has built-in features like composer support, debugging support, a browser,a terminal, and more.

Sample project

Now that the IDE is installed, let’s create a simple PHP project. Go to File →New → Project. From the resulting dialog, select PHP project. Enter a name for your project. There are some other options you might want to change, like changing the project’s default location, enabling JavaScript, and changing PHP version. See the following screenshot.

Create A New PHP Project in Eclipse

You can click the Finish button to create the project or press Next to configure other options like adding include and build paths. You don’t need to change those in most cases.

Once the project is created, right click on the project folder and select New → PHP File to add a new PHP file to the project. For this tutorial I named it index.php, the conventionally-recognized default file in every PHP project.

Then add the your code to the new file.

Demo PHP code

In the example above, I used CSS, JavaScript, and PHP tags on the same page mainly to show that the IDE is capable of supporting all of them together.

Once your page is ready, you can see the result output by moving the file to your web server document root or by creating a development PHP server in the project directory.

Thanks to the built-in terminal in Eclipse, we can launch a PHP development server right from within the IDE. Simply click the terminal icon on the toolbar (Terminal Icon) and click OK. In the new terminal, change to the project directory and run the following command:

php -S localhost:8080 -t . index.php
Terminal output

Now, open a browser and head over to http://localhost:8080. If everything has been done correctly per instructions and your code is error-free, you will see the output of your PHP script in the browser.

PHP output in Fedora
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Develop GUI apps using Flutter on Fedora

When it comes to app development frameworks, Flutter is the latest and greatest. Google seems to be planning to take over the entire GUI app development world with Flutter, starting with mobile devices, which are already perfectly supported. Flutter allows you to develop cross-platform GUI apps for multiple targets — mobile, web, and desktop — from a single codebase.

This post will go through how to install the Flutter SDK and tools on Fedora, as well as how to use them both for mobile development and web/desktop development.

Installing Flutter and Android SDKs on Fedora

To get started building apps with Flutter, you need to install

  • the Android SDK;
  • the Flutter SDK itself; and,
  • optionally, an IDE and its Flutter plugins.

Installing the Android SDK

Flutter requires the installation of the Android SDK with the entire Android Studio suite of tools. Google provides a tar.gz archive. The Android Studio executable can be found in the android-studio/bin directory and is called studio.sh. To run it, open a terminal, cd into the aforementioned directory, and then run:

$ ./studio.sh

Installing the Flutter SDK

Before you install Flutter you may want to consider what release channel you want to be on.

The stable channel is least likely to give you a headache if you just want to build a mobile app using mainstream Flutter features.

On the other hand, you may want to use the latest features, especially for desktop and web app development. In that case, you might be better off installing either the latest version of the beta or even the dev channel.

Either way, you can switch between channels after you install using the flutter channel command explained later in the article.

Head over to the official SDK archive page and download the latest installation bundle for the release channel most appropriate for your use case.

The installation bundle is simply a xz-compressed tarball (.tar.xz extension). You can extract it wherever you want, given that you add the flutter/bin subdirectory to the PATH environment variable.

Installing the IDE plugins

To install the plugin for Visual Studio Code, you need to search for Flutter in the Extensions tab. Installing it will also install the Dart plugin.

The same will happen when you install the plugin for Android Studio by opening the Settings, then the Plugins tab and installing the Flutter plugin.

Using the Flutter and Android CLI Tools on Fedora

Now that you’ve installed Flutter, here’s how to use the CLI tool.

Upgrading and Maintaining Your Flutter Installations

The flutter doctor command is used to check whether your installation and related tools are complete and don’t require any further action.

For example, the output you may get from flutter doctor right after installing on Fedora is:

Doctor summary (to see all details, run flutter doctor -v): [✓] Flutter (Channel stable, v1.12.13+hotfix.5, on Linux, locale it_IT.UTF-8) [!] Android toolchain - develop for Android devices (Android SDK version 29.0.2) ✗ Android licenses not accepted. To resolve this, run: flutter doctor --android-licenses [!] Android Studio (version 3.5) ✗ Flutter plugin not installed; this adds Flutter specific functionality. ✗ Dart plugin not installed; this adds Dart specific functionality. [!] Connected device ! No devices available ! Doctor found issues in 3 categories.

Of course the issue with the Android toolchain has to be resolved in order to build for Android. Run this command to accept the licenses:

$ flutter doctor --android-licenses

Use the flutter channel command to switch channels after installation. It’s just like switching branches on Git (and that’s actually what it does). You use it in the following way:

$ flutter channel <channel_name>

…where you’d replace <channel_name> with the release channel you want to switch to.

After doing that, or whenever you feel the need to do it, you need to update your installation. You might consider running this every once in a while or when a major update comes out if you follow Flutter news. Run this command:

$ flutter upgrade

Building for Mobile

You can build for Android very easily: the flutter build command supports it by default, and it allows you to build both APKs and newfangled app bundles.

All you need to do is to create a project with flutter create, which will generate some code for an example app and the necessary android and ios folders.

When you’re done coding you can either run:

  • flutter build apk or flutter build appbundle to generate the necessary app files to distribute, or
  • flutter run to run the app on a connected device or emulator directly.

When you run the app on a phone or emulator with flutter run, you can use the R button on the keyboard to use stateful hot reload. This feature updates what’s displayed on the phone or emulator to reflect the changes you’ve made to the code without requiring a full rebuild.

If you input a capital R character to the debug console, you trigger a hot restart. This restart doesn’t preserve state and is necessary for bigger changes to the app.

If you’re using a GUI IDE, you can trigger a hot reload using the bolt icon button and a hot restart with the typical refresh button.

Building for the Desktop

To build apps for the desktop on Fedora, use the flutter-desktop-embedding repository. The flutter create command doesn’t have templates for desktop Linux apps yet. That repository contains examples of desktop apps and files required to build on desktop, as well as examples of plugins for desktop apps.

To build or run apps for Linux, you also need to be on the master release channel and enable Linux desktop app development. To do this, run:

$ flutter config --enable-linux-desktop

After that, you can use flutter run to run the app on your development workstation directly, or run flutter build linux to build a binary file in the build/ directory.

If those commands don’t work, run this command in the project directory to generate the required files to build in the linux/ directory:

$ flutter create .

Building for the Web

Starting with Flutter 1.12, you can build Web apps using Flutter with the mainline codebase, without having to use the flutter_web forked libraries, but you have to be running on the beta channel.

If you are (you can switch to it using flutter channel beta and flutter upgrade as we’ve seen earlier), you need to enable web development by running flutter config –enable-web.

After doing that, you can run flutter run -d web and a local web server will be started from which you can access your app. The command returns the URL at which the server is listening, including the port number.

You can also run flutter build web to build the static website files in the build/ directory.

If those commands don’t work, run this command in the project directory to generate the required files to build in the web/ directory:

$ flutter create .

Packages for Installing Flutter

Other distributions have packages or community repositories to install and update in a more straightforward and intuitive way. However, at the time of writing, no such thing exists for Flutter. If you have experience packaging RPMs for Fedora, consider contributing to this GitHub repository for this COPR package.

The next step is learning Flutter. You can do that in a number of ways:

  • Read the good API reference documentation on the official site
  • Watching some of the introductory video courses available online
  • Read one of the many books out there today. [Check out the author’s bio for a suggestion! — Ed.]

Photo by Randall Ruiz on Unsplash.

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A quick introduction to Toolbox on Fedora

Toolbox allows you to sort and manage your development environments in containers without requiring root privileges or manually attaching volumes. It creates a container where you can install your own CLI tools, without installing them on the base system itself. You can also utilize it when you do not have root access or cannot install programs directly. This article gives you an introduction to toolbox and what it does.

Installing Toolbox

Silverblue includes Toolbox by default. For the Workstation and Server editions, you can grab it from the default repositories using dnf install toolbox.

Creating Toolboxes

Open your terminal and run toolbox enter. The utility will automatically request permission to download the latest image, create your first container, and place your shell inside this container. 

$ toolbox enter
No toolbox containers found. Create now? [y/N] y
Image required to create toolbox container.
Download registry.fedoraproject.org/f30/fedora-toolbox:30 (500MB)? [y/N]: y

Currently there is no difference between the toolbox and your base system. Your filesystems and packages appear unchanged. Here is an example using a repository that contains documentation source for a resume under a ~/src/resume folder. The resume is built using the pandoc tool.

$ pwd /home/rwaltr $ cd src/resume/ $ head -n 5 Makefile all: pdf html rtf text docx pdf: init pandoc -s -o BUILDS/resume.pdf markdown/* $ make pdf
bash: make: command not found
$ pandoc -v
bash: pandoc: command not found

This toolbox does not have the programs required to build the resume. You can remedy this by installing the tools with dnf. You will not be prompted for the root password, because you are running in a container.

$ sudo dnf groupinstall "Authoring and Publishing" -y && sudo dnf install pandoc make -y
... $ make all #Successful builds
mkdir -p BUILDS
pandoc -s -o BUILDS/resume.pdf markdown/*
pandoc -s -o BUILDS/resume.html markdown/*
pandoc -s -o BUILDS/resume.rtf markdown/*
pandoc -s -o BUILDS/resume.txt markdown/*
pandoc -s -o BUILDS/resume.docx markdown/*
$ ls BUILDS/
resume.docx resume.html resume.pdf resume.rtf resume.txt

Run exit at any time to exit the toolbox.

$ cd BUILDS/
$ pandoc --version || ls
pandoc 2.2.1
Compiled with pandoc-types 1.17.5.4, texmath 0.11.1.2, skylighting 0.7.5
...
for a particular purpose.
resume.docx resume.html resume.pdf resume.rtf resume.txt
$ exit logout
$ pandoc --version || ls
bash: pandoc: command not found...
resume.docx resume.html resume.pdf resume.rtf resume.txt

You retain the files created by your toolbox in your home directory. None of the programs installed in your toolbox will be available outside of it.

Tips and tricks

This introduction to toolbox only scratches the surface. Here are some additional tips, but you can also check out the official documentation.

  • Toolbox –help will show you the man page for Toolbox
  • You can have multiple toolboxes at once. Use toolbox create -c Toolboxname and toolbox enter -c Toolboxname
  • Toolbox uses Podman to do the heavy lifting. Use toolbox list to find the IDs of the containers Toolbox creates. Podman can use these IDs to perform actions such as rm and stop. (You can also read more about Podman in this Magazine article.)

Photo courtesy of Florian Richter from Flickr.

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Make your Python code look good with Black on Fedora

The Python programing language is often praised for its simple syntax. In fact the language recognizes that code is read much more often than it is written. Black is a tool that automatically formats your Python source code making it uniform and compliant to the PEP-8 style guide.

How to install Black on Fedora

Installing Black on Fedora is quite simple. Black is maintained in the official repositories.

$ sudo dnf install python3-black

Black is a command line tool and therefore it is run from the terminal.

$ black --help

Format your Python code with Black

Using Black to format a Python code base is straight forward.

$ black myfile.py
All done! ✨ 🍰 ✨ 1 file left unchanged.
$ black path_to_my_python_project/
All done! ✨ 🍰 ✨
165 files reformatted, 24 files left unchanged.

By default Black allows 88 characters per line, meaning that the code will be reformatted to fit within 88 characters per line. It is possible to change this to a custom value, for example :

$ black --line-length 100 my_python_file.py

This will set the line length to allow 100 characters.

Run Black as part of a CI pipeline

Black really shines when it is integrated with other tools, like a continuous integration pipeline.

The –check option allows to verify if any files need to be reformatted. This is useful to run as a CI test to ensure all your code is formatted in consistent manner.

$ black --check myfile.py
would reformat myfile.py
All done! 💥 💔 💥
1 file would be reformatted.

Integrate Black with your code editor

Running Black during the continuous integration tests is a great way to keep the code base correctly formatted. But developers really wants to forget about formatting and have the tool managing it for them.

Most of the popular code editors support Black. It allows developers to run the format tool every time a file is saved. The official documentation details the configuration needed for each editor.

Black is a must-have tool in the Python developer toolbox and is easily available on Fedora.

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CodeReady Containers: complex solutions on OpenShift + Fedora

Want to experiment with (complex) solutions on OpenShift 4.1+? CodeReady Containers (CRC) on a physical Fedora server is a great choice. It lets you:

  • Configure the RAM available to CRC / OpenShift (this is key as we’ll deploy Machine Learning, Change Data Capture, Process Automation and other solutions with significant memory requirements)
  • Avoid installing anything on your laptop
  • Standardize (on Fedora 30) so that you get the same results every time

Start by installing CRC and Ansible Agnostic Deployer (AgnosticD) on a Fedora 30 physical server. Then, you’ll use AgnosticD to deploy Open Data Hub on the OpenShift 4.1 environment created by CRC. Let’s get started!

Set up CodeReady Containers

$ dnf config-manager --set-enabled fedora
$ su -c 'dnf -y install git wget tar qemu-kvm libvirt NetworkManager jq libselinux-python'
$ sudo systemctl enable --now libvirtd

Let’s also add a user.

$ sudo adduser demouser
$ sudo passwd demouser
$ sudo usermod -aG wheel demouser

Download and extract CodeReady Containers:

$ su demouser
$ cd /home/demouser
$ wget https://mirror.openshift.com/pub/openshift-v4/clients/crc/1.0.0-beta.3/crc-linux-amd64.tar.xz
$ tar -xvf crc-linux-amd64.tar.xz
$ cd crc-linux-1.0.0-beta.3-amd64/
$ sudo cp ./crc /usr/bin

Set the memory available to CRC according to what you have on your physical server. For example, on a physical server with around 100GB you can allocate 80G to CRC as follows:

$ crc config set memory 81920
$ crc setup

You’ll need your pull secret from https://cloud.redhat.com/openshift/install/metal/user-provisioned.

$ crc start

That’s it — you can now login to your OpenShift environment: 

eval $(crc oc-env) && oc login -u kubeadmin -p <password> https://api.crc.testing:6443

Set up Ansible Agnostic Deployer

github.com/redhat-cop/agnosticd is a fully automated two-phase deployer. Let’s deploy it!

$ su demouser
$ cd /home/demouser
$ git clone https://github.com/redhat-cop/agnosticd.git
$ cd agnosticd/ansible
$ python -m pip install --upgrade --trusted-host files.pythonhosted.org -r requirements.txt
$ python3 -m pip install --upgrade --trusted-host files.pythonhosted.org -r requirements.txt
$ pip3 install kubernetes
$ pip3 install openshift
$ pip install kubernetes
$ pip install openshift

Set up Open Data Hub on Code Ready Containers

Open Data Hub is a machine-learning-as-a-service platform built on OpenShift and Kafka/Strimzi. It integrates a collection of open source projects.

First, create an Ansible inventory file with the following content.

$ cat inventory
$ 127.0.0.1 ansible_connection=local

Set up the WORKLOAD environment variable so that Ansible Agnostic Deployer knows that we want to deploy Open Data Hub.

$ export WORKLOAD="ocp4-workload-open-data-hub"
$ sudo cp /usr/local/bin/ansible-playbook /usr/bin/ansible-playbook

We are only deploying one Open Data Hub project, so set user_count to 1. You can set up workshops for many students by setting user_count.

An OpenShift project (with Open Data Hub in our case) will be created for each student.

$ eval $(crc oc-env) && oc login -u kubeadmin -p <password> https://api.crc.testing:6443
$ ansible-playbook -i inventory ./configs/ocp-workloads/ocp-workload.yml -e"ocp_workload=${WORKLOAD}" -e"ACTION=create" -e"user_count=1" -e"ocp_username=kubeadmin" -e"ansible_become_pass=<password>" -e"silent=False"
$ oc project open-data-hub-user1
$ oc get route
NAME HOST/PORT PATH SERVICES PORT TERMINATION WILDCARD
jupyterhub jupyterhub-open-data-hub-user1.apps-crc.testing jupyterhub 8080-tcp edge/Redirect None

On your laptop, add jupyterhub-open-data-hub-user1.apps-crc.testing to your /etc/hosts file. For example:

127.0.0.1 localhost fedora30 console-openshift-console.apps-crc.testing oauth-openshift.apps-crc.testing mapit-app-management.apps-crc.testing mapit-spring-pipeline-demo.apps-crc.testing jupyterhub-open-data-hub-user1.apps-crc.testing jupyterhub-open-data-hub-user1.apps-crc.testing

On your laptop:

$ sudo ssh marc@fedora30 -L 443:jupyterhub-open-data-hub-user1.apps-crc.testing:443

You can now browse to https://jupyterhub-open-data-hub-user1.apps-crc.testing.

Now that we have Open Data Hub ready, you could deploy something interesting on it. For example, you could deploy IBM’s Qiskit open source framework for quantum computing. For more information, refer to Video no. 9 at this YouTube playlist, and the Github repo here.

You could also deploy plenty of other useful tools for Process Automation, Change Data Capture, Camel Integration, and 3scale API Management. You don’t have to wait for articles on these, though. Step-by-step short videos are already available on YouTube.

The corresponding step-by-step instructions are also on YouTube. You can also follow along with this article using the GitHub repo.

Photo by Marta Markes on Unsplash.

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Announcing the release of Fedora 30 Beta

The Fedora Project is pleased to announce the immediate availability of Fedora 30 Beta, the next big step on our journey to the exciting Fedora 30 release.

Download the prerelease from our Get Fedora site:

Or, check out one of our popular variants, including KDE Plasma, Xfce, and other desktop environments, as well as images for ARM devices like the Raspberry Pi 2 and 3:

Beta Release Highlights

New desktop environment options

Fedora 30 Beta includes two new options for desktop environment. DeepinDE and Pantheon Desktop join GNOME, KDE Plasma, Xfce, and others as options for users to customize their Fedora experience.

DNF performance improvements

All dnf repository metadata for Fedora 30 Beta is compressed with the zchunk format in addition to xz or gzip. zchunk is a new compression format designed to allow for highly efficient deltas. When Fedora’s metadata is compressed using zchunk, dnf will download only the differences between any earlier copies of the metadata and the current version.

GNOME 3.32

Fedora 30 Workstation Beta includes GNOME 3.32, the latest version of the popular desktop environment. GNOME 3.32 features updated visual style, including the user interface, the icons, and the desktop itself. For a full list of GNOME 3.32 highlights, see the release notes.

Other updates

Fedora 30 Beta also includes updated versions of many popular packages like Golang, the Bash shell, the GNU C Library, Python, and Perl. For a full list, see the Change set on the Fedora Wiki. In addition, many Python 2 packages are removed in preparation for Python 2 end-of-life on 2020-01-01.

Testing needed

Since this is a Beta release, we expect that you may encounter bugs or missing features. To report issues encountered during testing, contact the Fedora QA team via the mailing list or in #fedora-qa on Freenode. As testing progresses, common issues are tracked on the Common F30 Bugs page.

For tips on reporting a bug effectively, read how to file a bug.

What is the Beta Release?

A Beta release is code-complete and bears a very strong resemblance to the final release. If you take the time to download and try out the Beta, you can check and make sure the things that are important to you are working. Every bug you find and report doesn’t just help you, it improves the experience of millions of Fedora users worldwide! Together, we can make Fedora rock-solid. We have a culture of coordinating new features and pushing fixes upstream as much as we can. Your feedback improves not only Fedora, but Linux and free software as a whole.

More information

For more detailed information about what’s new on Fedora 30 Beta release, you can consult the Fedora 30 Change set. It contains more technical information about the new packages and improvements shipped with this release.