feat(proposal): in-memory database without mlmd service

[Al-Pragliola]

Description

Builds on top of #425

In this proposal, I have added a new datastore as an alternative to mlmd for testing/development/static scenarios. This datastore acts as an in-memory database, it supports all actions possible on mlmd and specified in the openapi spec, and a seeding mechanism to have a common baseline in case of process exit/disturbance.

How Has This Been Tested?

docker build . -f Dockerfile -t docker.io/mr/mr:0.1.0

kind create cluster

kind load docker-image docker.io/mr/mr:0.1.0

kubectl create ns kubeflow

kubectl apply -k "./manifests/kustomize/overlays/inmemory"

kubectl patch deployment -n kubeflow model-registry-deployment --patch '{"spec": {"template": {"spec": {"containers": [{"name": "rest-container", "image": "mr/mr:0.1.0", "imagePullPolicy": "IfNotPresent"}]}}}}'

kubectl port-forward --namespace kubeflow svc/model-registry-service 8080:8080 &

curl -s -X 'POST' "localhost:8080/api/model_registry/v1alpha3/registered_models" -H 'accept: application/json' -H 'Content-Type: application/json' -d '{
      "description": "Iris scikit-learn model",
      "name": "iris"
}'

curl -s 'http://localhost:8080/api/model_registry/v1alpha3/registered_models?pageSize=100&orderBy=ID&sortOrder=DESC' -H 'accept: application/json' | jq

expected output:

{
  "items": [
    {
      "description": "loreum ipsum",
      "id": "1",
      "name": "test"
    },
    {
      "description": "loreum ipsum",
      "id": "2",
      "name": "test2"
    },
    {
      "description": "Iris scikit-learn model",
      "id": "3",
      "name": "iris",
      "state": "LIVE"
    }
  ],
  "nextPageToken": "",
  "pageSize": 1,
  "size": 3
}

Merge criteria:

• All the commits have been signed-off (To pass the DCO check)

• The commits have meaningful messages; the author will squash them after approval or in case of manual merges will ask to merge with squash.
• Testing instructions have been added in the PR body (for PRs involving changes that are not immediately obvious).
• The developer has manually tested the changes and verified that the changes work.
• Code changes follow the kubeflow contribution guidelines.

[google-oss-prow]

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