Start by getting the code:
git clone https://github.com/cockpit-project/cockpit
cd cockpit/
The remainder of the commands assume you're in the top level of the Cockpit git repository checkout.
Do not clone a fork! This will not work for various reasons (missing tags,
determining version, integration with bots commands). Please keep origin as
the read-only actual upstream project, and add your fork as a separate writable
remote, for example with
git remote add my [email protected]:yourgithubid/cockpit.git
The cockpit team maintains a cockpit/tasks container for both local development and CI. If you can install toolbx or distrobox on your system, it is highly recommended to do that:
- It is the official environment for CI, known to work, and gives you reproducible results.
- It avoids having to install development packages on your main machine.
- It avoids having to map the build and test dependencies to package names of various distributions.
-
Install
toolbox-
Fedora/CentOS/RHEL based distributions:
sudo dnf install toolbox -
Debian/Ubuntu based distributions:
sudo apt install podman-toolbox
-
-
Create a development toolbox for Cockpit
toolbox create --image ghcr.io/cockpit-project/tasks -c cockpit -
Enter the toolbox:
toolbox enter cockpit
Your home directory, user D-Bus, etc. are shared with the host, so you can
edit files as you normally would. Building and running tests happens inside the
toolbox container. If desired, you can install additional packages with
sudo dnf install.
The Cockpit team occasionally refreshes the tasks container image.
To re-create your development container from the latest image, run:
podman pull ghcr.io/cockpit-project/tasks
toolbox rm cockpit
...and then repeat steps 2 and 3 from above.
Most contributors want to work on the web (HTML, JavaScript, CSS) parts of Cockpit.
First, install Cockpit on your local machine as described in:
https://cockpit-project.org/running.html
Next, run this command from your top level Cockpit checkout directory, and make sure to run it as the same user that you'll use to log into Cockpit below.
mkdir -p ~/.local/share/
ln -s $(pwd)/dist ~/.local/share/cockpit
This will cause Cockpit to read JavaScript, HTML, and CSS files directly from the locally built package output directory instead of using the system-installed Cockpit files.
The recommended way to build bundles is to use the "watch" mode
(-w or--watch) on the page you are working on. For example, if you want to
work on anything in pkg/systemd, run:
./build.js -w systemd
See pkg/ for a list of all pages.
If you work on a change that affects multiple pages (such as a file in pkg/lib/), you can also build all pages:
./build.js -w
Now you can log into Cockpit on your local Linux machine at the following address, using the same username and password as your desktop login:
Watch mode automatically rebuilds when source files are modified. Once it
finishes building, refresh your browser to see the changes in Cockpit.
Press Ctrl-C to stop watch mode when you are done changing the code.
You often need to test code changes in a VM. You can set the $RSYNC env
variable to copy the built page into the given SSH target's
/usr/local/share/cockpit/ directory. If you use Cockpit's own test VMs and set up the
SSH c alias as described in test/README.md, you can use
one of these commands:
RSYNC=c ./build.js -w kdump
RSYNC=c ./build.js -w
To make Cockpit use system packages again, instead of your checkout directory, remove the symlink with the following command and log back into Cockpit:
rm ~/.local/share/cockpit
Cockpit uses autotools, so there are familiar ./configure script and
Makefile targets.
After a fresh clone of the Cockpit sources, you need to prepare them by running
autogen.sh like this:
./autogen.sh --prefix=/usr --enable-debug
As shown, autogen.sh runs 'configure' with the given options, and it also
prepares the build tree by downloading various nodejs dependencies.
When working with a Git clone, it is best to always run ./autogen.sh
instead of ./configure.
Then run
make
to build everything. Cockpit has a single non-recursive Makefile. You can only
run make from the top-level and it will always rebuild the whole project.
You can run unit tests of the current checkout:
make check
These should finish very quickly. It is a good practice to do this often.
For debugging individual tests, there are compiled binaries in the build directory. For QUnit tests (JavaScript), you can run
./test-server
which will output a URL to connect to with a browser, such as http://localhost:8765/qunit/base1/test-dbus.html. Adjust the path for different tests and inspect the results there.
QUnit tests are run as part of a pytest test called test_browser. You can
run individual tests via pytest -k, like so:
pytest -k test-fsinfo.html
You can see JavaScript code coverage information for QUnit tests. For a summary table:
pytest -k test_browser --js-cov
And for detailed output on uncovered sections in a specific file, something like:
pytest -k test-fsinfo.html --js-cov-files='*/fsinfo.ts'
Coverage information is gathered into the pytest tmpdir, regardless of which coverage-related commandline flags are given, so it's also possible to drill down after the fact — without re-running tests — using something like:
test/common/js_coverage.py -m '*/fsinfo.ts' /tmp/pytest-of-*/pytest-current/js-coverage/*
There are also static code and syntax checks which you should run often:
test/common/static-code
It is highly recommended to set up a git pre-push hook, to avoid pushing PRs that will fail on trivial errors:
ln -s ../../tools/git-hook-pre-push .git/hooks/pre-push
This calls test/common/static-code for each commit you're trying to push.
You can also set up a post-commit hook to do the same, after each commit:
ln -s ../../tools/git-hook-post-commit .git/hooks/post-commit
We also have a hook to ameliorate one of the more annoying drawbacks of using git submodules:
ln -s ../../tools/git-hook-pre-rebase .git/hooks/pre-rebase
Refer to the testing README for details on running the Cockpit integration tests locally.
The Cockpit bridge is the initial program launched in a Cockpit Linux session: Its stdin/out is connected to the web socket (and thus to JavaScript in the pages), where it speaks a JSON protocol that multiplexes "channels" -- abstractions of operating system APIs that the pages use to implement their functionality. This protocol is translated into operating system calls such as opening or writing files, D-Bus calls, or HTTP queries. Think of the bridge as the moral equivalent of "bash" in a human SSH session.
The bridge resides in src/cockpit with most of its rules in src/Makefile.am.
This directory was chosen because it matches the standard so-called "src
layout" convention for Python packages, where each package (cockpit) is a
subdirectory of the src directory.
The bridge can be used interactively on a local machine out of the source tree:
PYTHONPATH=src python3 -m cockpit.bridge
To make it easy to test out channels without having to write out messages
manually, cockpit.misc.print can be used:
PYTHONPATH=src python3 -m cockpit.misc.print open fsinfo path=/etc 'attrs=["type", "entries"]' | PYTHONPATH=src python3 -m cockpit.bridge
These shell aliases might be useful when experimenting with the protocol:
alias cpy='PYTHONPATH=src python3 -m cockpit.bridge'
alias cpf='PYTHONPATH=src python3 -m cockpit.misc.print'
To enable debug logging in journal on a test image, you can pass --debug to
image-prepare. This will set COCKPIT_DEBUG=all to /etc/environment, if
you are only interested channel debug messages change all to
cockpit.channel.
There are a growing number of pytest tests being written to test
the bridge code. You can run these with make pytest or
make pytest-cov. Those are both just rules to make sure that the
systemd_ctypes submodule is checked out before running pytest from the
source directory.
The tests require at least pytest 7.0.0 or higher to run.
Cockpit uses ESLint to automatically check JavaScript
code style in .js and .jsx files.
The linter is executed as part of test/common/static-code.
For developer convenience, the ESLint can be started explicitly by:
npm run eslint
Most rule violations can be automatically fixed by running:
npm run eslint:fix
Rules configuration can be found in the .eslintrc.json file.
During fast iterative development, you can also choose to not run eslint, by
running ./build.js with the -e/--no-eslint option. This
speeds up the build and avoid build failures due to ill-formatted comments,
unused identifiers, and other JavaScript-related issues.
Cockpit uses Stylelint to automatically check CSS code
style in .css and .scss files.
The linter is executed as part of test/common/static-code.
For developer convenience, the Stylelint can be started explicitly by:
npm run stylelint
But note that this only covers files in pkg/. test/common/static-code covers
all (S)CSS files tracked in git.
Some rule violations can be automatically fixed by running:
npm run stylelint:fix
Rules configuration can be found in the .stylelintrc.json file.
During fast iterative development, you can also choose to not run stylelint, by
running ./build.js with the -s/--no-stylelint option. This speeds up the
build and avoids build failures due to ill-formatted CSS or other issues.
If you want to safely test your local changes directly on it, Cockpit supports
installation as a systemd-sysext.
This covers all parts of Cockpit (ws, tls, session, bridge, login page, systemd
units, PAM configuration, and the session pages) except for the SELinux policy.
It gets installed into /run/extensions/, so nothing ever hits the disk and
this also works on read-only installations (CoreOS, OSTree, bootc).
Just run:
tools/make-sysext
This runs ./autogen.sh if necessary, and then just re-makes your tree,
re-installs it into /run/extensions, and reloads the sysext in systemd.
Afterwards you can connect to http://localhost:9090 as usual.
To remove this, reboot or run
tools/make-sysext stop
Attention: This is not currently compatible with SELinux in enforcing mode. If you have that, you need to disable it:
sudo setenforce 0
If the above systemd-sysext approach does not work for you, you can also test changes with some bind mounts.
To test changes to the login page, you can bind-mount the build tree's
dist/static/ directory over the system one:
sudo mount -o bind dist/static/ /usr/share/cockpit/static/
Likewise, to test changes to the branding, use:
sudo mount -o bind src/branding/ /usr/share/cockpit/branding/
After that, run systemctl stop cockpit.service to ensure that the web server
restarts on the next browser request.
To make Cockpit use system-installed code again, umount the paths:
sudo umount /usr/share/cockpit/static/ /usr/share/cockpit/branding/
systemctl stop cockpit.service
Similarly, if you change cockpit-ws itself, you can make the system (systemd
units, cockpit-tls, etc.) use this:
sudo mount -o bind cockpit-ws /usr/libexec/cockpit-ws
On Debian-based OSes (including Ubuntu), the path will be
/usr/lib/cockpit/cockpit-ws instead.
On Fedora, CentOS, Red Hat Enterprise Linux, and related distributions, you also need to disable SELinux with:
sudo setenforce 0
for this to work, as your local build tree does not otherwise have the expected SELinux type.
Some cockpit binaries rely on specific paths in /usr/share or libexecdir to be
set correctly. By default they are set to /usr/local.
On RPM based systems, this can be set using an autogen.sh argument; afterwards you need to rebuild:
./autogen.sh rpm
make
sudo make install
This will install Cockpit and all support files. If you have a Fedora/RHEL/CentOS based distribution, install a PAM configuration with
sudo cp tools/cockpit.pam /etc/pam.d/cockpit
If you have a Debian/Ubuntu based distribution, install this PAM config instead:
sudo cp tools/cockpit.debian.pam /etc/pam.d/cockpit
For other distributions you need to create a PAM config yourself.
If you prefer to install to a different --prefix and would prefer
that make install not write outside that prefix, then specify the
--enable-prefix-only option to autogen.sh. This will result in an
installation of Cockpit that does not work without further tweaking.
For advanced users only.
Instead of a direct make install as above, you can also build distribution
packages and install them. This is generally more robust, as they upgrade and
remove cleanly, and don't interfere with distribution packages in /usr.
In a Fedora/RHEL build environment you can build binary RPMs with
tools/make-rpms --quick
In a Debian/Ubuntu build environment you can build debs with
tools/make-debs --quick
During a normal build from a git checkout, the node_modules will be
automatically unpacked from a cache kept in a separate git repository. You can
force the unpack to occur using the tools/node-modules checkout command, but
this shouldn't be necessary. In the event that you need to modify
package.json (to install a new module, for example) then you'll need to run
tools/node-modules install to create a new cache from the result of running
npm install on your new package.json.
Your locally rebuilt changes to node_modules won't be used by others. A new
version will be created by a GitHub workflow when you open your pull request.
The tools/node-modules script inspects the GITHUB_BASE environment variable
to determine the correct repository to use when fetching and pushing. It will
strip the repository name (leaving the project- or username) and use the
node-cache.git repository in that namespace. If GITHUB_BASE is unset, it
will default to cockpit-project/node-cache.git.
A local cache is maintained in ~/.cache/cockpit-dev.
Make a pull request on github.com with your change. All changes get reviewed, tested, and iterated on before getting into Cockpit. The general workflow is described in the wiki.
You need to be familiar with git to contribute a change. Do your changes on a branch. Your change should be one or more git commits that each contain one single logical simple reviewable change, without modifications that are unrelated to the commit message.
Don't feel bad if there's multiple steps back and forth asking for changes or tweaks before your change gets in. If you fix your commits after getting a review, just force-push to your branch -- this will update the pull request automatically. Do not close it and open a new one; that would destroy the conversation and reviews.
Cockpit is a designed project. Anything that the user will see should have design done first. This is done on the wiki and mailing list.
Bigger changes need to be discussed on the #cockpit:fedoraproject.org Matrix channel or our mailing list [email protected] before you invest too much time and energy.
Feature changes should have a video and/or screenshots that show the change. This video should be uploaded directly to GitHub on the pull request or issue or uploaded to YouTube or another service that allows video embedding.
Use a command like this to record a video including the browser frame:
recordmydesktop -x 1 -y 200 --width 1024 --height 576 \
--fps 24 --freq 44100 --v_bitrate 2000000
(This command only works on X11 and requires the recordmydesktop program to
be installed.)
You can also resize your browser window and move it to the right location with
a script. In Firefox you can open the Scratchpad (Shift+F4) and enter the
following commands:
window.resizeTo(1024, 576);
window.moveTo(1, 200);
Then run it with Ctrl+R when the browser is showing an empty tab, e.g.
about:newtab. You may need to adjust the positions for your environment.
All messages from the various cockpit processes go to the journal and can be seen with commands like:
sudo journalctl -f
Much of Cockpit has verbose internal debug logging that can be enabled when trying to track down a problem. To turn it on add a file to your system like this:
sudo mkdir -p /etc/systemd/system/cockpit.service.d
sudo sh -c 'printf "[Service]\nEnvironment=G_MESSAGES_DEBUG=cockpit-ws,cockpit-bridge\nUser=root\nGroup=\n" > /etc/systemd/system/cockpit.service.d/debug.conf'
sudo systemctl daemon-reload
sudo systemctl restart cockpit
In the above command you'll notice the string "cockpit-ws". This is a log domain. There are various log domains you can enable:
- cockpit-bridge: Cockpit bridge detailed debug messages
- cockpit-protocol: Very verbose low level traffic logging
- cockpit-ws: Cockpit Web Service detailed debug messages
- WebSocket: Verbose low level WebSocket logging
To revert the above logging changes:
sudo rm /etc/systemd/system/cockpit.service.d/debug.conf
sudo systemctl daemon-reload
sudo systemctl restart cockpit
Various javascript methods in Cockpit can show debug messages. You can turn them
on by setting a window.debugging global, or setting up a debugging property
in the browser storage. To do this run the following in your javascript console:
>> sessionStorage.debugging = "all"
You'll notice that there's a ton of messages that get shown. If you want to be more specific, instead of "all" use one or more of the following specific types:
"all" // All available debug messages
"channel" // All channel messages sent to server
"dbus" // DBus related debug messages
"http" // HTTP (via the server) related debug messages
"spawn" // Debug messages related to executing processes
There are other strings related to the code you may be working on. For example,
the metrics page shows debug information with the value metrics. Do
git grep window.debugging pkg to find out all available ones.
In addition, if you want your debug setting to survive a browser refresh or Cockpit log out, use something like:
>> localStorage.debugging = "spawn"
Cockpit uses React for the JavaScript frontend, React Developer Tools is a browser extension to inspect React components, edit props and state. Out of the box the developer tools do not work with Cockpit due to the pages being loaded in a separate iframe. A workaround is to load the page directly by embedding, for example for the system overview page:
http://localhost:9090/cockpit/@localhost/system/index.html
This loads the system overview as a standalone page allowing React Developer tools to inspect its state.
You may want to run cockpit-ws under a debugger such as valgrind or gdb. You can run these processes as your own user, although you won't be able to debug all the authentication logic in those cases.
First of all, make sure Cockpit is correctly installed. Even though we will be
running cockpit-ws from the built sources, this still relies on some of the right
software being installed in order for Cockpit to work. (Such as: PAM stack,
UI files, cockpit-bridge, etc.)
This is how you would run cockpit-ws under gdb:
export G_DEBUG=fatal-criticals
export G_MESSAGES_DEBUG=cockpit-ws,cockpit-wrapper,cockpit-bridge
gdb --args ./cockpit-ws --port 10000 --no-tls
And you can run cockpit-ws and cockpit-bridge under valgrind like this:
export G_DEBUG=fatal-criticals
export G_MESSAGES_DEBUG=cockpit-ws,cockpit-wrapper,cockpit-bridge
valgrind --trace-children=yes --trace-children-skip='*unix_chkpwd*' \
./cockpit-ws --port 10000 --no-tls
Note that cockpit-session and cockpit-bridge will run from the installed prefix, rather than your build tree.
If at all possible, use the cockpit/tasks container with toolbox/distrobox as documented above. Installing all necessary development packages manually on your machine is intrusive, error prone, difficult, and hard to debug.
You will need at least node.js and NPM.
On Fedora or CentOS (>= 9):
sudo dnf install npm
On Debian/Ubuntu:
sudo apt install npm
For running tests, the following dependencies are required:
sudo dnf install curl expect xz rpm-build chromium-headless dbus-daemon \
libvirt-daemon-driver-storage-core libvirt-daemon-driver-qemu libvirt-client python3-libvirt \
python3-pyyaml
For compiling the C parts, you will need the package build dependencies:
sudo dnf install dnf-utils python-srpm-macros
sudo dnf builddep --spec tools/cockpit.spec