distribution/BUILDING.md

Building the registry source

Use-case

This is useful if you intend to actively work on the registry.

Alternatives

Most people should use the official Registry docker image.

People looking for advanced operational use cases might consider rolling their own image with a custom Dockerfile inheriting FROM registry:2.

The latest updates to main branch are automatically pushed to distribution Docker Hub repository with edge tag.

Gotchas

You are expected to know your way around with Go & git.

If you are a casual user with no development experience, and no preliminary knowledge of Go, building from source is probably not a good solution for you.

Configure the development environment

The first prerequisite of properly building distribution targets is to have a Go development environment setup. Please follow How to Write Go Code for proper setup. If done correctly, you should have a GOROOT and GOPATH set in the environment.

Next, fetch the code from the repository using git:

git clone https://github.com/distribution/distribution
cd distribution

If you are planning to create a pull request with changes, you may want to clone directly from your fork.

Build and run from source

First, build the binaries:

$ make
+ bin/registry
+ bin/digest
+ bin/registry-api-descriptor-template
+ binaries

Now create the directory for the registry data (this might require you to set permissions properly)

mkdir -p /var/lib/registry

... or alternatively export REGISTRY_STORAGE_FILESYSTEM_ROOTDIRECTORY=/somewhere if you want to store data into another location.

The registry binary can then be run with the following:

$ ./bin/registry --version
./bin/registry github.com/distribution/distribution/v3 v2.7.0-1993-g8857a194

The registry can be run with a development config using the following incantation:

$ ./bin/registry serve cmd/registry/config-dev.yml
INFO[0000] debug server listening :5001
WARN[0000] No HTTP secret provided - generated random secret. This may cause problems with uploads if multiple registries are behind a load-balancer. To provide a shared secret, fill in http.secret in the configuration file or set the REGISTRY_HTTP_SECRET environment variable.  environment=development go.version=go1.18.3 instance.id=e837df62-a66c-4e04-a014-b063546e82e0 service=registry version=v2.7.0-1993-g8857a194
INFO[0000] endpoint local-5003 disabled, skipping        environment=development go.version=go1.18.3 instance.id=e837df62-a66c-4e04-a014-b063546e82e0 service=registry version=v2.7.0-1993-g8857a194
INFO[0000] endpoint local-8083 disabled, skipping        environment=development go.version=go1.18.3 instance.id=e837df62-a66c-4e04-a014-b063546e82e0 service=registry version=v2.7.0-1993-g8857a194
INFO[0000] using inmemory blob descriptor cache          environment=development go.version=go1.18.3 instance.id=e837df62-a66c-4e04-a014-b063546e82e0 service=registry version=v2.7.0-1993-g8857a194
INFO[0000] providing prometheus metrics on /metrics
INFO[0000] listening on [::]:5000                        environment=development go.version=go1.18.3 instance.id=e837df62-a66c-4e04-a014-b063546e82e0 service=registry version=v2.7.0-1993-g8857a194

If it is working, one should see the above log messages.

Build reference

The regular go commands, such as go test, should work per package.

A Makefile has been provided as a convenience to support repeatable builds.

Run make to build the binaries:

$ make
+ bin/registry
+ bin/digest
+ bin/registry-api-descriptor-template
+ binaries

The above provides a repeatable build using the contents of the vendor directory. We can verify this worked by running the registry binary generated in the "./bin" directory:

$ ./bin/registry --version
./bin/registry github.com/distribution/distribution v2.0.0-alpha.2-80-g16d8b2c.m

Run make test to run all of the tests.

Run make validate to run the validators, including the linter and vendor validation. You must have docker with the buildx plugin installed to run the validators.

Optional build tags

Optional build tags can be provided using the environment variable BUILDTAGS.

noresumabledigest

Compiles without resumable digest support

include_gcs

Adds support for Google Cloud Storage

Local cloud storage environment

You can run an S3 API compatible storage locally with minio.

You must have docker compose installed on your workstation.

Start the local cloud environment:

make start-cloud-storage

There is a sample registry configuration file that lets you point the registry to the started storage:

AWS_ACCESS_KEY=distribution \
        AWS_SECRET_KEY=password \
        AWS_REGION=us-east-1 \
        S3_BUCKET=images-local \
        S3_ENCRYPT=false \
        REGION_ENDPOINT=http://127.0.0.1:9000 \
        S3_SECURE=false \
./bin/registry serve tests/conf-local-cloud.yml

Stop the local storage when done:

make stop-cloud-storage