Docker Hub Proxy

A simple Python Flask REST server to proxy calls to Docker Hub.

Usage

The Docker Hub API is implemented using agithub and supports authenticated calls using these environment variables:

• DOCKERHUB_USERNAME: a valid Docker Hub username
• DOCKERHUB_PASSWORD: password for the same Docker Hub account
• DOCKERHUB_TOKEN: alternatively an authenticated Docker Hub token can be used instead of username and password

To get a reference to the DockerHub class use something like:

api = DockerHub(username=os.environ.get('DOCKERHUB_USERNAME'),
                password=os.environ.get('DOCKERHUB_PASSWORD'),
                token=os.environ.get('DOCKERHUB_TOKEN'))

The api.DockerHub class wraps endpoints with the following methods:

• get_user_details(username): Returns the details of a Docker Hub user.
• get_repositories(username, <page_size>, <limit>): Returns all the repositories of a user.
  It will paginate through pages having page_size results at most (default: 100) and will limit the total maximum results to limit (default: 10000)
• get_repository(username, repository_name): Returns the details of a single repository.
• get_tags(username, repository_name, <page_size>, <limit>): Returns all the available tags of a repository.
  It will paginate through pages having page_size results at most (default: 100) and will limit the total maximum results to limit (default: 1000)
• get_dockerfile(username, repository_name): Returns the contents of the raw Dockerfile of a repository.
• get_autobuild_settings(username, repository_name): Returns the autobuild settings of a repository.
  It will only work for autobuilds.
• get_comments(username, repository_name, <page_size>, <limit>): Returns all the comments of a repository. It will paginate through pages having page_size results at most (default: 100) and will limit the total maximum results to limit (default: 1000)
• get_build_history(username, repository_name, <page_size>, <limit>): Returns the details for all the builds of a repository. It will paginate through pages having page_size results at most (default: 100) and will limit the total maximum results to limit (default: 1000)
• get_build_details(username, repository_name, build_code): Returns the details of a single build of a repository.

The app module is responsible for the REST presentation layer exposing JSON endpoints. The exposed endpoints are cached using Flask-Cache.

Configuration options:

• HTTP_HOST: the host (interface) for Flask to bind to (default: 127.0.0.1)
• HTTP_PORT: the port to bind to (default: 5000)
• CORS_ORIGINS: comma separated list of origins to allow cross-domain GET requests from (default: http://localhost:?.*)

To allow connections from other hosts apart from localhost set the HTTP_PORT environment variable to 0.0.0.0 or as appropriate.

List of endpoints:

• /users/<username>: returns the Docker Hub user's details
• /repositories/<username>: returns the user's repositories
• /repositories/<username>/<repository>: returns the details of a single repository
• /repositories/<username>/<repository>/tags: returns the available tags of a repository
• /repositories/<username>/<repository>/dockerfile: returns the raw Dockerfile of a repository (for autobuilds)
• /repositories/<username>/<repository>/autobuild: returns the autobuild settings of a repository
• /repositories/<username>/<repository>/comments: returns the comments of a repository
• /repositories/<username>/<repository>/builds: returns the list of builds for a repository
• /repositories/<username>/<repository>/builds/<build_code>: returns the details of a single build for a repository

Docker

The web application is built as a Docker image too based on Alpine Linux for 3 architectures with the following tags:

• latest: for x86 hosts
  
• armhf: for 32-bits ARM hosts
  
• aarch64: for 64-bits ARM hosts
  

latest is auto-built on Docker Hub while the ARM builds are uploaded from Travis.

To run it:

docker run -d --name="dockerhub-proxy" -p 5000:5000          \
  -e DOCKERHUB_USERNAME='user' -e DOCKERHUB_PASSWORD='pass'  \
  -e CORS_ORIGINS='http://site.example.com,*.website.com'    \
  rycus86/dockerhub-proxy:latest

Or with docker-compose (for a Raspberry Pi for example):

version: '2'
services:

  dockerhub-proxy:
    image: rycus86/dockerhub-proxy:armhf
    read_only: true
    expose:
      - "5000"
    restart: always
    environment:
      - HTTP_HOST=0.0.0.0
    env_file:
      - dockerhub-secrets.env

This way you can keep the secrets in the env_file instead of passing them to the Docker client from the command line.