Welcome! We’re excited that you’re interested in contributing. Below are some basic guidelines.
Cortex follows a standard GitHub pull request workflow. If you’re unfamiliar with this workflow, read the very helpful Understanding the GitHub flow guide from GitHub.
You are welcome to create draft PRs at any stage of readiness - this can be helpful to ask for assistance or to develop an idea. But before a piece of work is finished it should:
- Be organised into one or more commits, each of which has a commit message that describes all changes made in that commit (‘why’ more than ‘what’ - we can read the diffs to see the code that changed).
- Each commit should build towards the whole - don’t leave in back-tracks and mistakes that you later corrected.
- Have tests for new functionality or tests that would have caught the bug being fixed.
- Include a CHANGELOG message if users of Cortex need to hear about what you did.
- If you have made any changes to flags or config, run
make docand commit the changed files to update the config file documentation.
Cortex projects uses
goimports tool (
go get golang.org/x/tools/cmd/goimports to install) to format the Go files, and sort imports. We use goimports with
-local github.com/cortexproject/cortex parameter, to put Cortex internal imports into a separate group. We try to keep imports sorted into three groups: imports from standard library, imports of 3rd party packages and internal Cortex imports. Goimports will fix the order, but will keep existing newlines between imports in the groups. We try to avoid extra newlines like that.
You’re using an IDE you may find useful the following settings for the Cortex project:
Developer Certificates of Origin (DCOs)
Before submitting your work in a pull request, make sure that all commits are signed off with a Developer Certificate of Origin (DCO). Here’s an example:
git commit -s -m "Here is my signed commit"
You can find further instructions here.
(By default, the build runs in a Docker container, using an image built
with all the tools required. The source code is mounted from where you
make into the build container as a Docker volume.)
To run the test suite:
You may need to load the Docker images into your minikube environment. There is a convenient rule in the Makefile to do this:
Then run Cortex in minikube:
kubectl apply -f ./k8s
(these manifests use
latest tags, i.e. this will work if you have
just built the images and they are available on the node(s) in your
Cortex will sit behind an nginx instance exposed on port 30080. A job is deployed to scrape itself. Try it:
If that doesn’t work, your Minikube might be using a different ip address. Check with
To add or update a new dependency, use the
go get command:
# Pick the latest tagged release. go get example.com/some/module/pkg # Pick a specific version. go get example.com/some/module/[email protected]
Tidy up the
go mod tidy go mod vendor git add go.mod go.sum vendor git commit
You have to commit the changes to
go.sum before submitting the pull request.
You will find a docs folder in this project that is turned into the website that you will find at cortexmetrics.io.
Note: If you attempt to view pages on Github it’s likely that you might find broken links or pages. That is expected and should not be address unless it is causing issues with the site that is produced as part of the build.
To build the Hugo based documentation web site
make clean-doc check-doc web-build
To run the site locally
- After building the site above
- Install Hugo
Execute the following command to start the web server