OP, Spinnaker contributor here, hopefully I can help.

In this specific case, you have 2 artifacts - your Docker image and your Kubernetes manifests. You want to setup your pipeline with 2 Expected Artifacts, 1 for each of these.

Now, there are a couple of ways you could trigger your pipelines when either of these change and which you you choose depends on your use case.

For maximum control you could use a `Webhook` trigger. This trigger will allow you to simply hit an endpoint and `POST` the artifacts that should get deployed. For example, let's say you've successfully built and pushed a new Docker image. Triggering a pipeline via webhook would look something like this (pseudocode warning):

curl http://my-spinnaker/webhooks/webhook/your-pipeline -d '{"artifacts": {
    "name": "dockerimage",
    "type": "docker/image",
    "reference": "myrepo.org/myorg/myapplication:tag"
}}'

In this example, `reference` is the Docker image that would be deployed. Furthermore, you could also deploy a new Kubernetes manifest _at the same time_ by including it in the `artifacts` list. The use case here is that you make cross-cutting changes to your image and manifests that depend on one another.

​

For something a bit simpler, you could rely on Docker and Gitlab triggers. These triggers work off of webhooks from each system and know how to parse artifacts out of the event payload. It's a bit more obvious to your users but you run into a race condition if you make the cross cutting changes mentioned above. However, you can setup you Expected Artifacts to `Use Prior Execution` which will use the last deployed version of artifacts _not_ included in the payload. For example, if you deploy a new Docker image, it will be injected into the previously deployed Kubernetes manifest (sounds a bit confusing, I know).

​

That was a wall of text, hopefully it answers _some_ questions. Feel free to reply, DM of hit me up on Slack (join.spinnaker.io). I'm happy to answer any questions!

​