Mu Ruby template

Template for running Ruby/Sinatra microservices

Using the template

Extend the semtech/mu-ruby-template and set a maintainer. That's it.

Configure your entrypoint through the environment variable APP_ENTRYPOINT (default: web.rb). You can use the Gemfile as you would expect.

Example Dockerfile

FROM semtech/mu-ruby-template:1.2.0-ruby2.1 
MAINTAINER Erika Pauwels <erika.pauwels@gmail.com>
# ONBUILD of mu-ruby-template takes care of everything

Configuration

The SPARQL endpoint can be configured through the MU_SPARQL_ENDPOINT environment variable. By default this is set to http://database:8890/sparql. In that case the triple store used in the backend should be linked to the login service container as database.

The MU_APPLICATION_GRAPH environment variable specifies the graph in the triple store the microservice will work in. By default this is set to http://mu.semte.ch/application. The graph name can be used in the service via settings.graph.

Develop a microservice using the template

To use the template while developing your app, start a container in development mode with your code folder mounted in /app:

docker run --volume /path/to/your/code:/app
            -e RACK_ENV=development
        -d semtech/mu-ruby-template:1.2.0-ruby2.1 

Changes will be automatically picked up by Sinatra.

Helper methods

The template provides the user with several helper methods.

log

The template provides a log object to the user for logging. Just do log.info "Hello world". The log level can be set through the LOG_LEVEL environment variable (default: info, values: debug, info, warn, error, fatal).

Logs are written to the /logs directory in the docker container.

generate_uuid()

Generate a random UUID (String).

session_id_header(request)

Get the session id from the request headers.

rewrite_url_header(request)

Get the rewrite URL from the request headers.

validate_json_api_content_type(request)

Validate whether the Content-Type header contains the JSONAPI Content-Type. Returns a 400 otherwise.

validate_resource_type(expected_type, data)

Validate whether the type specified in the JSON data is equal to the expected type. Returns a 409 otherwise.

error(title, status = 400)

Returns a JSONAPI compliant error response with the given status code (default: 400).

query(query)

Executes the given SPARQL select query.

update(query)

Executes the given SPARQL update query.

update_modified(subject, modified = DateTime.now.xmlschema)

Executes a SPARQL query to update the modification date of the given subject URI (string). The date defaults to now.

Writing tests for your microservice

To test your app, run the container with RACK_ENV set to test. All rspec tests matching *_spec.rb in spec/ and its subdirectories will be executed.

docker run --rm -e RACK_ENV=test microservice-image

To run the tests while developing, start an interactive container in the test enviroment with your code folder mounted in /app:

docker run --volume /path/to/your/code:/app
            -e RACK_ENV=test
            -it semtech/mu-ruby-template:1.2.0-ruby2.1 /bin/bash

You can now run your tests inside the container with:

bundle install
rspec -c