Contribution Guide
How to contribute to the project
We’re happy you’re interested in contributing to the Tetragon project.
This section of the Tetragon documentation will help you make sure you
have an environment capable of testing changes to the Tetragon source code,
and that you understand the workflow of getting these changes reviewed and
merged upstream.
Clone and provision an environment
Make sure you have a GitHub account.
Fork the Tetragon repository to your GitHub user or organization.
Turn off GitHub actions for your fork as described in the
GitHub Docs.
This is recommended to avoid unnecessary CI notification failures on the fork.
Clone your ${YOUR_GITHUB_USERNAME_OR_ORG}/tetragon
fork into your
GOPATH
, and set up the base repository as upstream
remote:
mkdir -p "${GOPATH}/src/github.com/cilium"
cd "${GOPATH}/src/github.com/cilium"
git clone https://github.com/${YOUR_GITHUB_USERNAME_OR_ORG}/tetragon.git
cd tetragon
git remote add upstream https://github.com/cilium/tetragon.git
Prepare your Development setup,
see section below.
Check the GitHub issues for good tasks to get
started.
Follow the steps in Making changes to start contributing. Welcome :)!
1 - Development setup
This will help you getting started with your development setup to build Tetragon
Building and Running Tetragon
For local development, you will likely want to build and run bare-metal Tetragon.
Requirements:
- go 1.18
- GNU make
- A running docker service
libcap
and libelf
(in Debian systems, e.g., install libelf-dev
and
libcap-dev
)
You can build Tetragon as follows:
If you want to use podman
instead of docker
, you can do the following (assuming you
need to use sudo
with podman
):
CONTAINER_ENGINE='sudo podman' make
You can ignore /bin/sh: docker: command not found
in the output.
To build using the local clang, you can use:
CONTAINER_ENGINE='sudo podman' LOCAL_CLANG=1 LOCAL_CLANG_FORMAT=1 make
See
Dockerfile.clang
for the minimal required version of clang
.
You should now have a ./tetragon
binary, which can be run as follows:
sudo ./tetragon --bpf-lib bpf/objs
Notes:
The --bpf-lib
flag tells Tetragon where to look for its compiled BPF
programs (which were built in the make
step above).
If Tetragon fails with an error "BTF discovery: candidate btf file does not exist"
, then make sure that your kernel support BTF,
otherwise place a BTF file where Tetragon can read it and specify its path
with the --btf
flag.
Running Code Generation
Tetragon uses code generation based on protoc to generate large amounts of
boilerplate code based on our protobuf API. We similarly use automatic
generation to maintain our k8s CRDs. Whenever you make changes to these files,
you will be required to re-run code generation before your PR can be accepted.
To run codegen from protoc, run the following command from the root of the
repository:
And to run k8s CRD generation, run the following command from the root of the repository:
Finally, should you wish to modify any of the resulting codegen files (ending
in .pb.go
), do not modify them directly. Instead, you can edit the files in
cmd/protoc-gen-go-tetragon
and then re-run make codegen
.
Building and running a Docker image
The base kernel should support BTF
or a BTF file should be bind mounted on top of /var/lib/tetragon/btf
inside
container.
To build Tetragon image:
To run the image:
docker run --name tetragon \
--rm -it -d --pid=host \
--cgroupns=host --privileged \
-v /sys/kernel/btf/vmlinux:/var/lib/tetragon/btf \
cilium/tetragon:latest \
bash -c "/usr/bin/tetragon"
Run the tetra
binary to get Tetragon events:
docker exec -it tetragon \
bash -c "/usr/bin/tetra getevents -o compact"
Building and running as a systemd service
To build Tetragon tarball:
Running Tetragon in kind
The scripts in contrib/localdev will help you run Tetragon locally in a kind
cluster. First, ensure that docker, kind, kubectl, and helm are installed on
your system. Then, run the following commands:
# Build Tetragon agent and operator images
make LOCAL_CLANG=0 image image-operator
# Bootstrap the cluster
contrib/localdev/bootstrap-kind-cluster.sh
# Install Tetragon
contrib/localdev/install-tetragon.sh --image cilium/tetragon:latest --operator cilium/tetragon-operator:latest
Verify that Tetragon is installed by running:
kubectl get pods -n kube-system
Local Development in Vagrant Box
If you are on a Mac, use Vagrant to create a dev VM:
vagrant up
vagrant ssh
make
If you are getting an error, you can try to run sudo launchctl load /Library/LaunchDaemons/org.virtualbox.startup.plist
(from a Stackoverflow
answer).
Local Development in Minikube
You can also run the tetragon agent directly (instead of in a pod). Here we
describe how this can be done in minikube:
minikube start --driver=kvm2
minikube mount $HOME:$HOME # so that we can use .kube/config
./tetragon-operator --kube-config ~/.kube/config
make STATIC=1 tetragon
minikube ssh -- 'sudo mkdir -p /var/run/cilium/tetragon'
minikube ssh sudo "sh -c 'NODE_NAME=minikube /home/kkourt/src/tetragon/tetragon --bpf-lib /home/kkourt/src/tetragon/bpf/objs --server-address unix:///var/run/cilium/tetragon/tetragon.sock --enable-k8s-api --k8s-kubeconfig-path /home/kkourt/.kube/config'"
What’s next
2 - Making changes
Learn how to make your first changes to the project
Make sure the main branch of your fork is up-to-date:
git fetch upstream
git checkout main
git merge upstream/main
For further reference read
github syncing a fork
documentation.
Create a PR branch with a descriptive name, branching from main:
git switch -c pr/${GITHUB_USERNAME_OR_ORG}/changes-to-something main
Make the changes you want.
Separate the changes into logical commits.
- Describe the changes in the commit messages. Focus on answering the
question why the change is required and document anything that might be
unexpected.
- If any description is required to understand your code changes, then those
instructions should be code comments instead of statements in the commit
description.
- For submitting PRs, all commits need to be signed off
(git commit -s)
.
See the section Developer’s Certificate of Origin
Make sure your changes meet the following criteria:
- New code is covered by Integration Testing.
- End to end integration / runtime tests have been extended or added. If not
required, mention in the commit message what existing test covers the new
code.
- Follow-up commits are squashed together nicely. Commits should separate
logical chunks of code and not represent a chronological list of changes.
Run git diff --check
to catch obvious white space violations
Build Tetragon with your changes included.
What’s next
4 - Submitting a pull request
Learn how to submit a pull request to the project
Submitting a pull request
Contributions must be submitted in the form of pull requests against the
upstream GitHub repository at https://github.com/cilium/tetragon.
Fork the Tetragon repository.
Push your changes to the topic branch in your fork of the repository.
Submit a pull request on https://github.com/cilium/tetragon.
Before hitting the submit button, please make sure that the following
requirements have been met:
Each commit compiles and is functional on its own to allow for bisecting of
commits.
All code is covered by unit and/or runtime tests where feasible.
All changes have been tested and checked for regressions by running the
existing testsuite against your changes.
All commits contain a well written commit description including a title,
description and a Fixes: #XXX
line if the commit addresses a particular
GitHub issue identified by its number. Note that the GitHub issue will be
automatically closed when the commit is merged.
doc: add contribution guideline and how to submit pull requests
Tetragon Open Source project was just released and it does not include
default contributing guidelines.
This patch fixes this by adding:
1. CONTRIBUTING.md file in the root directory as suggested by github documentation: https://docs.github.com/en/communities/setting-up-your-project-for-healthy-contributions/setting-guidelines-for-repository-contributors
2. Development guide under docs directory with a section on how to submit pull requests.
3. Moves the DEVELOP.md file from root directory to the `docs/contributing/development/` one.
Fixes: #33
Signed-off-by: Djalal Harouni <djalal@cilium.io>
Note: Make sure to include a blank line in between commit title and commit description.
All commits are signed off. See the section Developer’s Certificate of
Origin.
All important steps in Making changes have been followed.
5 - Developer's certificate of origin
Learn about the “sign-off” procedure
To improve tracking of who did what, we’ve introduced a “sign-off” procedure,
make sure to read and apply the
Developer’s Certificate of Origin.