[installer] Make ws-manager-bridge configurable

[andrew-farries]

Description

One of the Webapp team's epics for Q2 is to use the Gitpod installer to deploy to Gitpod SaaS. In order to do that we will need to add additional configuration to the installer to make the output suitable for a SaaS deployment as opposed to a self-hosted deployment.

This PR allows the ws-manager-bridge component to control whether or not it should register itself as a workspace cluster. For self hosted installations it should do so but for SaaS, where we run separate workspace clusters, it should not.

Related Issue(s)

Part of #9097

How to test

Create an installer config file containing this experimental section:

experimental:
  webapp:
    wsManagerBridge:
      skipSelf: true

Get a versions.yaml for use with the installer:

docker run -it --rm "eu.gcr.io/gitpod-core-dev/build/versions:${version}" cat versions.yaml > versions.yaml

Then invoke the installer as:

go run . render --debug-version-file versions.yaml --config /path/to/config --use-experimental-config

The ws-manager-bridge config will contain the following when skipSelf is false:

  ws-manager-bridge.json: |-
    {
      "installation": "default",
      "staticBridges": [
        {
          "name": "default",
          "url": "dns:///ws-manager:8080",
          "tls": {
            "ca": "/ws-manager-client-tls-certs/ca.crt",
            "crt": "/ws-manager-client-tls-certs/tls.crt",
            "key": "/ws-manager-client-tls-certs/tls.key"
          },
          "state": "available",
          "maxScore": 100,
          "score": 50,
          "govern": true,
          "admissionConstraints": null
        }
      ],

and the staticBridges key will be [] when skipSelf is true.

Likewise the WSMAN_CFG_MANAGERS env var in the server component will change according to the value of skipSelf (but the json is bas64 encoded).

Release Notes

Allow `ws-manager-bridge` service to skip registering itself as a workspace, via the installer.

Documentation

None.

[geropl]

Nice 👍