Strict schema for k8s objects for values.yaml

[mik-laj]

Some fields in values.yml accept value that complies with the Kubernetes API, so we can verify that too.

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[mik-laj]

We are now only missing a few types to have full and strict coverage.
Before:

$ cat chart/values.schema.json | jq 'recurse | objects | select(.type == "object") | select(.properties == null) | select(.["$ref"] == null) | select(.additionalProperties == null)' | jq -s 'length'
57
$ cat chart/values.schema.json | jq 'recurse | objects | select(.type  == "array") | select(.items == null)' | jq -s 'length'
51

After:

$ cat chart/values.schema.json | jq 'recurse | objects | select(.type == "object") | select(.properties == null) | select(.["$ref"] == null) | select(.additionalProperties == null)' | jq -s 'length'
3
$ cat chart/values.schema.json | jq 'recurse | objects | select(.type  == "array") | select(.items == null)' | jq -s 'length'
10

[mik-laj]

CC: @simplylizz

[0ex-d]

Still looks like WIP to me, keep it up

[mik-laj]

@mrbaguvix I have currently solved all the issues with the structure of objects. Now only the issues with the structures of the array remain, but I think we can solve that as a separate contribution. It is important to me that most of the problems are resolved, so following contributions that follow the conventions in this file will also declare the complete structure of the objects. Previously, even when someone wanted to use a reference, they weren't sure if it was a good idea. Here is example: #19175 (comment)

[mik-laj]

I have resolved all the problems except the following

$ cat chart/values.schema.json | jq 'recurse | objects | select(.type  == "array") | select(.items == null)'

{
  "description": "HTTP paths to add to the web Ingress before the default path.",
  "type": "array",
  "default": []
}
{
  "description": "HTTP paths to add to the web Ingress after the default path.",
  "type": "array",
  "default": []
}
{
  "description": "Additional mappings for StatsD exporter.",
  "type": "array",
  "default": []
}

1 and 2: I don't know the correct structure. This field is also not covered by tests.
3: I did not find the schema.json file for this parameter.

[jedcunningham]

Overall LGTM.

I'm wondering if we should hold this until after we cut 1.3.0 and have our next release be 2.0.0. I could easily see folks having extra config in their values and this stricter schema being surprising. Thoughts?

[github-actions]

The PR is likely OK to be merged with just subset of tests for default Python and Database versions without running the full matrix of tests, because it does not modify the core of Airflow. If the committers decide that the full tests matrix is needed, they will add the label 'full tests needed'. Then you should rebase to the latest main or amend the last commit of the PR, and push it with --force-with-lease.

[mik-laj]

I could easily see folks having extra config in their values and this stricter schema being surprising. Thoughts?

As for fields that have a structure defined with an external reference, users cannot define additional fields as this will cause an invalid k8s object to be generated. Here is an example: #19379

The problem is only with the objects that are defined in this schema, but we can remove them from this contribution and change them in the future.

[mik-laj]

I deleted all added additionalProperties fields. It should be safe now.

[potiuk]

LGTM. There are some helm unit tests failures though.

[mik-laj]

I looked at the CI problem and I think the OpenAPI specification has a bug.

ResourceQuotaSpec has the following definition:
https://github.com/yannh/kubernetes-json-schema/blob/master/v1.21.0/resourcequotaspec.json

{
  "properties": {
    "hard": {
      "additionalProperties": {
        "$ref": "https://raw.githubusercontent.com/yannh/kubernetes-json-schema/master/v1.21.0/_definitions.json#/definitions/io.k8s.apimachinery.pkg.api.resource.Quantity"
      },
      "type": [
        "object",
        "null"
      ]
    },
...

and
quantity has been defined as follow:
https://github.com/yannh/kubernetes-json-schema/blob/master/v1.21.0/quantity.json

{
  "oneOf": [
    {
      "type": "string"
    },
    {
      "type": "number"
    }
  ],
  "$schema": "http://json-schema.org/schema#",
  "type": "object"
}

The fields oneOf and type are mutually exclusive. For now, I've copied the type definitions directly into the spec.

[mik-laj]

Here issue: yannh/kubernetes-json-schema#11