mock-DRS

Connexion-based mockup service implementing parts of the GA4GH Data Repository Service (DRS) API schema. The service was developed to implement and test TEStribute, a task distribution logic package for TES instances.

Usage

Once deployed and started (see below), the service is available at:
http://localhost:9101/ga4gh/drs/v1/

You can explore the service via the Swagger UI:

firefox http://localhost:9101/ga4gh/drs/v1/ui/

The specifications, in JSON format, can be retrieved with:

wget http://localhost:9101/ga4gh/drs/v1/swagger.json

Note that host and port can be set manually in the config file. In that case, the values in the URLs above need to be replaced as well.

The client DRS-cli can be used to send requests to the service.

Deployment

mock-DRS can be deployed via containers (preferred) or after manual installation of all dependencies.

In both cases, the repository first needs to be cloned with:

git clone git@github.com:elixir-europe/mock-DRS.git

Afterwards traverse to the repository's root directory:

cd mock-DRS

Containerized Deployment

"Production-like" containerized deployment without HTTP server/load balancer etc.

Requirements (containerized deployment)

• Git (tested with version 2.17.1)
• Docker (tested with version 18.09.6)
• docker-compose (tested with version 1.24.0)

Building & starting the service

# Build application image
# [NOTE] Image re-building is not always necessary. Inspect the `Dockerfile`
#        to check which changes will need re-building.
docker-compose build
# Start service
docker-compose up -d

Other useful commands

# Check logs
docker-compose logs
# Shut down service
docker-compose down

Non-containerized deployment

Deployment for local development without containers, HTTP server/load balancer etc.

Requirements (non-containerized deployment)

• Git (tested with version 2.17.1)
• Python (tested with versions 2.7.15+ & 3.6.8)
• pip (tested with version 19.1.1)
• virtualenv (tested with version 15.1.0)

Installing & starting the service

# Set up Python virtual environment
virtualenv -p `which python3` venv
source venv/bin/activate

# Install dependencies
pip install -r requirements.txt

# Install app
python setup.py develop

# Run service
python mock_drs/Server.py

IMPORTANT: You will also need to replace host mongo with localhost in the database section of the config file.

Implementation details

Note that only those parts of the service are implemented that are required for developing, testing and debugging TEStribute. For all other endpoints only stubs are implemented that return the most basic valid response (typically an "empty" JSON object).

Assumptions not warranted by DRS specifications

• As the current DRS specifications do not provide a means to identify identical objects across DRS instances (e.g., via a mandatory checksum), TEStribute assumes that DRS identifiers (property id of Object model) are globally unique across the network of DRS instances. While this assumption is not warranted by the specifications, it might perhaps be possible to enforce a common naming scheme at least within a given organization, until a more sustainable solution arises.

The DRS Database

When starting the service, the DRS is automatically populated with a set of objects from a data objects file. The identifiers of the objects that the database is populated with are in turn specified in the config file.

Custom data objects

IMPORTANT: When populating DRS instances for the use with TEStribute in the manner described here, you must ensure that all object identfiers are globally unique across the entire network of connected/used DRS services. See the section on assumptions not warranted by DRS specifications for details.

The service can be configured to be started with different data objects by first editing/amending the data objects file and then editing the database -> objects section of the config file before starting the service. Only objects specified in data objects are available to the DRS service at startup, so make sure that any object that is added to the config file has a corresponding entry in the data objects file.

Alternatively (and preferably), objects available to the DRS can be modified in the running service via the /update-db endpoint, which is particularly useful for setting up environments for various testing scenarios for TEStribute. The endpoint is defined in a dedicated OpenAPI specification:

    /update-db:
    post:
      summary: Object id's in the array that need to be added to the db
      operationId: updateDatabaseObjects
      consumes:
        - application/json
      produces:
        - application/json
      parameters:
        - name: body
          in: body
          description: ''
          schema:
            $ref: '#/definitions/UpdateObject'
          required: true
      responses:
        200:
          description: "200 response"
          schema:
              $ref: '#/definitions/UpdatedDB'
      tags:
        - DataRepositoryService
      x-swagger-router-controller: ga4gh.drs.server

It relies on the following models:

UpdatedDB:
  type: object
  properties:The service can be configured with different unit costs for CPU and memory
    objects:
      type: ausage, data transfer and storage. Default values for the corresponding
      items:
        type:parameters are listed in `task_info` section of the service's [config] and they
UpdateObject:can be edited by the user before starting the service.
  type: object
  properties:
    clear:
      type: boolean
    data_objects:
      type: array
      items:
        $ref: '#/definitions/Object'

The model UpdateObject in turn relies on the Object model of the DRS specifications, commit cd0186f, a snapshot of which is also shipped with this repository.

DRS-cli can be used to communicate with the /update-db endpoint.

Note that while the /update-db endpoint can be accessed via the same root URI (and explored via the Swagger UI), it was not included in the DRS specifications, but rather is added to it on the fly when the service service is started.

Contributing

This project is a community effort and lives off your contributions, be it in the form of bug reports, feature requests, discussions, or fixes and other code changes. Please read the contributing guidelines if you want to contribute. And please mind the code of conduct for all interactions with the community.

Versioning

Development of the app is currently still in alpha stage, and current versioning is for internal use only. In the future, we are aiming to adopt semantic versioning that is synchronized to the versioning of TEStribute and DRS-cli in order to ensure that these apps will be compatible as long as both their major and minor versions match.

License

This project is covered by the Apache License 2.0 also available shipped with this repository.

Contact

Please contact the project leader for inquiries, proposals, questions etc. that are not covered by the Contributing section.

Acknowledgments

The project is a collaborative effort under the umbrella of the ELIXIR Cloud and AAI group. It was started during the 2019 Google Summer of Code as part of the Global Alliance for Genomics and Health organization.