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
the read-only actual upstream project, and add your fork as a separate writable
remote, for example with
git remote add my firstname.lastname@example.org:yourgithubid/cockpit.git
Setting up development container
- 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.
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 quay.io/cockpit/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 quay.io/cockpit/tasks toolbox rm cockpit
…and then repeat steps 2 and 3 from above.
Working on Cockpit’s session pages
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
Now you can log into Cockpit on your local Linux machine at the following address. Use the same user and password that you used to log into your Linux desktop.
After every change to the source files, bundles need to be rebuilt. The
recommended and fastest way is to do that is using the “watch” mode (
--watch) on the page that 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:
Note that this enables eslint and stylelint by default – if you want to
disable them, run it with
Reload cockpit in your browser after page is built. Press
stop watch mode once you are done with changing the code.
You often need to test code changes in a VM. You can set the
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
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:
Working on the non-web parts of Cockpit
Cockpit uses autotools, so there are familiar
./configure script and
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
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
to build everything. Cockpit has a single non-recursive Makefile. You can only
make from the top-level and it will always rebuild the whole project.
You can run unit tests of the current checkout:
These should finish very quickly. It is a good practice to do this often.
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.
You can also run individual tests by specifying the
make check TESTS=qunit/base1/test-chan.html
There are also static code and syntax checks which you should run often:
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
test/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
Running the integration test suite
Refer to the testing README for details on running the Cockpit integration tests locally.
Most distro releases now ship a replacement for the C bridge written in Python.
It resides in
src/cockpit with most of its rules in
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
Running the bridge
The Python bridge can be used interactively on a local machine:
PYTHONPATH=src python3 -m cockpit.bridge
To make it easy to test out channels without having to write out messages
cockpit.misc.print can be used:
PYTHONPATH=src python3 -m cockpit.misc.print open fslist1 path=/etc watch=False | 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'
When working with the Python bridge on test images, note that
ubuntu-2204 still use the C bridge. So if you want to
explicitly have the Python bridge on those images use:
To enable debug logging in journal on a test image, you can pass
image-prepare. This will set
you are only interested channel debug messages change
Testing the Python bridge
There are a growing number of Python
unittest tests being written to test
parts of the new 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
The tests require at least
pytest 7.0.0 or higher to run.
code style in
The linter is executed on every build.
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
During fast iterative development, you can also choose to not run eslint, by
./build.js with the
--no-eslint option. This
speeds up the build and avoid build failures due to ill-formatted comments,
Cockpit uses Stylelint to automatically check CSS code
The linter is executed on every build.
For developer convenience, the Stylelint can be started explicitly by:
npm run stylelint
Some rule violations can be automatically fixed by running:
npm run stylelint:fix
Rules configuration can be found in the
During fast iterative development, you can also choose to not run stylelint, by
./build.js with the
--no-stylelint option. This speeds up the
build and avoids build failures due to ill-formatted CSS or other issues.
Working on your local machine: Web server
To test changes to the login page or any other resources, you can bind-mount the
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
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
On RPM based systems, this can be set using an autogen.sh argument; afterwards you need to rebuild:
Installation from upstream sources
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
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.
Build distribution packages
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
In a Fedora/RHEL build environment you can build binary RPMs with
In a Debian/Ubuntu build environment you can build debs with
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
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.
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
A local cache is maintained in
Contributing a change
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. Don’t feel bad if there’s multiple steps back and forth asking for changes or tweaks before your change gets in.
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.
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.
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
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
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.
Debug logging of Cockpit processes
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
on by setting a
window.debugging global, or setting up a
>> 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
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"
Running Cockpit processes under a debugger
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
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.
Manually installing the development dependencies
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
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-flake8 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