brigdrake

BrigDrake

BrigDrake provides Drake pipeline support for Brigade.

THIS PROJECT HIGHLY VOLATILE!

brigdrake implements the highly volatile DrakeSpec and, as such is, itself, highly volatile. Users are warned that breaking changes to this software are likely at any point up until its eventual 1.0 release.

Installation

Currently, BrigDrake recommends creating a new Brigade instance that is separate from any existing Brigade instance you may already have. This is because BrigDrake requires specific Brigade configuration that would not be conducive to building traditional, brigade.js-based Brigade projects.

The BrigDrake installation process is somewhat involved, but this is owed to the complexity of creating a new GitHub App and isn't attributable to Brigade or BrigDrake itself.

The installation process takes this general shape:

1. Install the brigdrake Helm chart.
2. Create a GitHub "app."
3. Update brigdrake with details generated during the GitHub app creation process.

The next few sections cover each of these in greater detail.

Prerequisites

This documentation assumes you're installing BrigDrake into a Kuberntes cluster that is capable of provisioning internet-facing load balancers. i.e. It is easiest to follow along using a cluster deployed to one of the public clouds.

Do not expect these instructions to work with minikube.

Install the Helm Chart

This documentation counts a detailed Helm overview as out of scope, so some basic Helm knowledge is assumed.

Start by adding the brigdrake chart repository to Helm:

$ helm repo add brigdrake https://lovethedrake.github.io/brigdrake

Proceed by installing the brigdrake chart. Initial installation can usually be carried out using the chart's default configuration. We'll re-configure it later once critical values are known.

$ helm install brigdrake/brigdrake --name brigdrake --namespace brigdrake

Post-installation, wait for the brigdrake-brigade-github-app service in the brigdrake namespace to obtain an external IP. Take note of this IP. You will it in subsequent steps.

$ kubectl get service brigdrake-brigade-github-app -n brigdrake

Create a GitHub "App"

Proceed to the settings page for the GitHub user or organization that owns the repositories you wish to build using BrigDrake. A menu on the left should contain a Developer settings sub-section. The options in that section may be different depending on whether you're viewing settings for a user or an organization, but in either case, drill down into this section until you find an option to create a new Github App. (Do not create a new OAuth App. This is a different thing.)

1. Select a GitHub App Name. This name must be globally unique. When the form is submitted, validation will inform you if the name you have selected is already in use by another Github App.

2. The value of the Homepage URL field is largely unimportant. It can be set to any valid URL. Consider using the GitHub user or organization's GitHub page.

3. Similarly, the User authorization callback URL will be unused in our scenario and can be set to any valid URL. Again, consider using the GitHub user or organization's GitHub page.

4. Webhook URL should incorporate the external IP of the brigdrake-brigade-github-app service (see previous section) and take the following form: http://<IP>/events/github.

5. Webhook secret should be a strong password. Take note of whatever value you use. You will need it in subsequent steps.

6. Set the following permissions:

   • Checks: Read & write
     • Only needed if you want job statuses reported back to GitHub. This requires additional project-level setup that isn't currently documented.
   • Repository contents: Read-only
   • Repository metadata: Read-only
   • Pull requests: Read-only

7. Subscribe to the following events:

   • Pull request
   • Push

8. Submit the form.

9. When the App has been successfully created, you will be taken to a confirmation page.

   1. The page will prompt you to generate a private key. Follow the link to do so and download the key. Note this is your only opportunity to do so. You cannot retrieve the key later; you can only replace it with a new one.

Update the BrigDrake Installation

Now that the GitHub App has been created, GitHub users, GitHub organizations, or individual GitHub repositories that install/enable that app will securely transmit events to BrigDrake's brigade-github-app gateway. This gateway, requires some re-configuration with details from the previous section in order to decrypt those secure payloads.

Extract the full set up configuration options from the brigdrake chart and save them to a file:

$ helm inspect values brigdrake/brigdrake > my-brigdrake-values.yaml

Open the my-brigdrake-values.yaml in your favorite editor and find the brigade-github-app section. Under that section is another named github. Here, you will override three default values with details from the previous section.

• key must be configured with the entire contents of the private key file downloaded in the previous section. Pay special attention to syntax and indentation when setting the value for this field. (See example below.)

• defaultSharedSecret must be set to the same shared secret we used when creating the GitHub App.

Example:

  brigade-github-app:
    # ...
    github:
      key: |
        -----BEGIN RSA PRIVATE KEY-----
        MIIEpQIBAAKCAQEA/O4FNQYB2boyyO++cGMSawSzoKGNCIZ0J3NiS+y+CIsK7EXn
        mskOJY3.........................................................
        ................................................................
        ................................................................
        ................................................................
        ................................................................
        ................................................................
        ................................................................
        ................................................................
        ........................... This is a ..........................
        ........................... fake key. ..........................
        ................................................................
        ................................................................
        ................................................................
        ................................................................
        ................................................................
        ................................................................
        ................................................................
        ................................................................
        ................................................................
        ................................................................
        ................................................................
        ................................................................
        ................................................................
        ....................................RfVw9nXXvmgyT0=
        -----END RSA PRIVATE KEY-----
      # ...
      defaultSharedSecret: UXn+lZdEvLXpPCQOfoRR

Now update the brigdrake installation with this new configuration:

$ helm upgrade brigdrake brigdrake/brigdrake --values my-brigdrake-values.yaml

Use

After following all the installation instructions, GitHub users, GitHub organizations, or individual GitHub repositories that install/enable the GitHub App will securely transmit events to your installation of BrigDrake.

Ultimately, BrigDrake is just Brigade pre-configured with Drake pipeline support, so a Brigade project must be created for any project you wish to build using BrigDrake. Absent corresponding project configuration, Brigade (and thus, brigdrake) will not respond to any of the events it receives.

To create a Brigade project, use the brig tool. Pre-built binaries for common OSes and CPU architectures can be found on the Brigade releases page.

$ brig project create --namespace brigdrake

This is an interactive process. Follow the prompts. Default options and values should be acceptable for nearly all fields, but when prompted for the shared secret source, select Leave undefined. This will ensure the default shared secret for the entire Brigade instance is used.

With the project created, related events emitted from GitHub should trigger Drake pipelines according to triggers defined in the project's Drakefile.yaml.

For an example Drakefile.yaml, refer to the brigdrake-demo project. If desired, you can fork that repository and push commits to the fork to see BrigDrake in action.

Once triggered, a Drake pipeline built by BrigDrake is little different from any typical Brigade build. All knowledge of Brigade and associated tools carries over to BrigDrake.

These instructions count a complete overview of Brigade as out of scope, but do check out Kashti (the Brigade UI) to see events and the builds and pipeline executions they triggered. You can get the IP for Kashti as follows:

$ kubectl get service brigdrake-kashti -n brigdrake

Limitations

At present, BrigDrake only integrates with GitHub. i.e. Pipeline execution can only be triggered, at this time, by events emitted by GitHub and received by Brigade via the brigade-github-app gateway.

This may change in the near future as both the BrigDrake project and the DrakeSpec mature.

Contributing

This project accepts contributions via GitHub pull requests. The Contributing document outlines the process to help get your contribution accepted.

Code of Conduct

Although not a CNCF project, this project abides by the CNCF Code of Conduct.