Model Registry

Model registry provides a central repository for model developers to store and manage models, versions, and artifacts metadata. A Go-based application that leverages ml_metadata project under the hood.

Red Hat's Pledge

• Red Hat drives the project's development through Open Source principles, ensuring transparency, sustainability, and community ownership.
• Red Hat values the Kubeflow community and commits to providing a minimum of 12 months' notice before ending project maintenance after the initial release.

Alpha

This Kubeflow component has alpha status with limited support. See the Kubeflow versioning policies. The Kubeflow team is interested in your feedback about the usability of the feature.

Documentation links:

1. Introduction

• What is Kubeflow Model Registry
• Blog KF 1.9 introducing Model Registry

2. Installation

• installing Model Registry standalone
• installing Model Registry with Kubeflow manifests
• installing Model Registry using ODH Operator

3. Concepts

• Logical Model

4. Python client

• installing and using the Model Registry Python client

5. Tutorials

• end-to-end tutorial
• demonstration video

6. FAQs
7. Development

• introduction to local build and development
• contributing
• Kubeflow community and the Model Registry working group
• REST API
  • OpenAPI definition
  • playground
• license scanning
• monitoring image quality

Pre-requisites:

• go >= 1.21
• protoc v24.3 - Protocol Buffers v24.3 Release
• npm >= 10.2.0 - Installing Node.js and npm
• Java >= 11.0
• python 3.9

OpenAPI Proxy Server

The model registry proxy server implementation follows a contract-first approach, where the contract is identified by model-registry.yaml OpenAPI specification.

You can also easily display the latest OpenAPI contract for model-registry in a Swagger-like editor directly from this repository; for example, here.

Starting the OpenAPI Proxy Server

Run the following command to start the OpenAPI proxy server from source:

make run/proxy

The proxy service implements the OpenAPI defined in model-registry.yaml to create a Model Registry specific REST API on top of the existing ml-metadata server.

NOTE The ml-metadata server must be running and accessible from the environment where model-registry starts up.

Model registry logical model

For a high-level documentation of the Model Registry logical model, please check this guide.

Model Registry Core

The model registry core is the layer which implements the core/business logic by interacting with the underlying ml-metadata server. It provides a model registry domain-specific api that is in charge to proxy all, appropriately transformed, requests to ml-metadata using gRPC calls.

Model registry library

For more background on Model Registry Go core library and instructions on using it, please check getting started guide.

Development

Building

Run the following command to build the server binary:

make build

The generated binary uses spf13 cmdline args. More information on using the server can be obtained by running the command:

./model-registry --help

Run the following command to clean the server binary, generated models and etc.:

make clean

Testing

Run the following command to trigger all tests:

make test

or, to see the statement coverage:

make test-cover

Docker Image

Building the docker image

The following command builds a docker image for the server with the tag model-registry:

docker build -t model-registry .

Note that the first build will be longer as it downloads the build tool dependencies. Subsequent builds will re-use the cached tools layer.

Running the proxy server

NOTE: ml-metadata server must be running and accessible, see more info on how to start the gRPC server in the official ml-metadata documentation.

The following command starts the proxy server:

docker run -d -p <hostname>:<port>:8080 --user <uid>:<gid> --name server model-registry proxy -n 0.0.0.0

Where, <uid>, <gid>, and <host-path> are the same as in the migrate command above. And <hostname> and <port> are the local ip and port to use to expose the container's default 8080 listening port. The server listens on localhost by default, hence the -n 0.0.0.0 option allows the server port to be exposed.

Running model registry & ml-metadata

NOTE: Docker compose must be installed in your environment.

There are two docker-compose files that make the startup of both model registry and ml-metadara easier, by simply running:

docker compose -f docker-compose[-local].yaml up

The main difference between the two docker compose files is that -local one build the model registry from source, the other one, instead, download the latest pushed quay.io image.

When shutting down the docker compose, you might want to clean-up the SQLite db file generated by ML Metadata, for example ./test/config/ml-metadata/metadata.sqlite.db

Testing architecture

The following diagram illustrate testing strategy for the several components in Model Registry project:

Go layers components are tested with Unit Tests written in Go, as well as Integration Tests leveraging Testcontainers. This allows to verify the expected "Core layer" of logical data mapping developed implemented in Go, matches technical expectations.

Python client is also tested with Unit Tests and Integration Tests written in Python.

End-to-end testing is developed with Pytest and Robot Framework; this higher-lever layer of testing is used to demonstrate User Stories from high level perspective.

FAQ

How do I delete metadata resources using the Model Registry API?

MR utilizes a common ARCHIVED status for all types. To delete something, simply update its status.

Tips

Pull image rate limiting

Ocassionally you may encounter an 'ImagePullBackOff' error when deploying the Model Registry manifests. See example below for the model-registry-db container.

Failed to pull image “mysql:8.3.0”: rpc error: code = Unknown desc = fetching target platform image selected from image index: reading manifest sha256:f9097d95a4ba5451fff79f4110ea6d750ac17ca08840f1190a73320b84ca4c62 in docker.io/library/mysql: toomanyrequests: You have reached your pull rate limit. You may increase the limit by authenticating and upgrading: https://www.docker.com/increase-rate-limit

This error is triggered by the rate limits from docker.io; in this example specifically about the image mysql:8.3.0 (the expanded reference is docker.io/library/mysql:8.3.0). To mitigate against this error you could authenticate using image pull secrets for local development; or replace the image used with alternative mirrored images, for instance with the following example:

manifests/kustomize/overlays/db/model-registry-db-deployment.yaml file.

spec.template.spec.containers.image: public.ecr.aws/docker/library/mysql:8.3.0