# GitLab Serverless Events TL;DR; 1. Work on GitLab Event Source that is deployable from within GitLab (a managed application) 1. Installing the event source from GitLab deploys it along with a secret / key to a cluster. 1. Installing the event source configures GitLab Webhook and sets the event source sink address. 1. Installing the event source connects the webhook secret / private key with the cluster secret / public key. 1. Event source controller transform a webhook in a cloud event payload and propagates it within the cluster. 1. A user configures `events: ` in `serverless.yaml` and defines relationships between functions and events. 1. `gitlabktl` creates all necessary resources when deploying functions to make sure that events are being routed through a valid broker to a valid function. ## Description In GitLab Serverless we currently do not support triggering functions when some kind of an event occurs. We also do not support configuring / defining relationships between events and functions. ## The Event Source In order to propagate events in a Knative cluster we need GitLab Event Source. We do have two GitLab Event Sources that we might work on more: 1. Triggermesh `gitlabsource` :arrow_right: https://gitlab.com/triggermesh/gitlabsource 1. Knative-source GitLab Event Source :arrow_right: https://github.com/knative/eventing-sources/pull/382 We need to work on one of them, and make them installable from the GitLab UI. ## Integration Once someone clicks "Install" button, next to the even source app, we are going to: 1. Create a secret token or public/private key pair and deploy one of these (token or a public key) to a cluster. 1. Create a webhook in GitLab and connect it with a GitLab Event Source Controller / Manager endpoint in a cluster. 1. Create a webhook token or transform webhook into a signed JWT 1. Create a resource of `GitLabSource` and later (during deployment) `Trigger` / `Broker` to route events to a function / set of functions ## Configuration We need to make it possible for users to define relationship between events and functions. We do have a few issues mentioning events: 1. https://gitlab.com/gitlab-org/gitlab-ce/issues/61709 1. https://gitlab.com/gitlab-org/gitlab-ce/issues/61171 Current proposal for configuration: ```yaml functions: echo: handler: MyEcho.my_function source: echo-rb/ runtime: runtimes/ruby description: "echo function using Ruby runtime" trigger: - new_merge_request_created events: new_merge_request_created: cloud_event: type: knative.gitlab.merge_request.created # or, both ways correct gitlab: webhook: new_merge_request_created # or however we call that in a webhook payload ``` There are some technical details that I decided to skip when creating this issue, but perhaps this is a good start to foster discussion about it and eventually moving forward. /cc @danielgruesso @DylanGriffith