Finding a Rate with Ruby - delivered with Rails.
You can run this app locally or on Docker, please run make in the project root dir to find out more about the menu options.
As of this writing, the following menu options are available:
% make
console Jump into the Rails console and interact with the services
docker-hop-on Jump on the docker instance
docker-remove-container Stops and removes the container
docker-run-container Run the container (one right now)
docker-run-tests Run the tests in the container
docker-setup Sets up the app using Docker and Docker Compose
generate-swagger-doc Generate Swagger documentation
run-example-no-result Run an example that finds a rate
run-example Run an example that finds a rate
run Run the Rails app with an example JSON file locally
test Run the tests
The app needs Ruby 2.6.3 with bundler installed. Run bundle install in the project root directory, that will install all the necessary gems into the vendor/bundle directory.
Run the app with make run, navigate to http://localhost:3000 and you should see the Swagger documentation.
Use the make docker-setup command to build the image from the provided Dockerfile and to create the instance. Once it's completed, navigate to http://localhost:3000 with your browser, that will redirect your request to the Swagger generated API documentation.
The application business logic is in app/models/entities directory. The tests to exercise the logic is in the corresponding spec dir.
The JSON rates are parsed into ParkingRate objects. These objects are pivoted to TimeslotsForDay entities when the app is loaded and stored in the Globals class. The RateFinder class is responsible finding the rate for the provided start time and end time.
The application was developed as a console app, it can be extract into a different component if needed, Ruby on Rails was used as an API layer to deliver this functionality over http.
I don't have an endpoint to reload the rates from JSON on the fly. The user has to alter the JSON rates locally, and restart the Rails process to load the updated configuration values into memory.
The Swagger documentation is generated from integration tests. Right now there is only one, to exercise the rates/find POST endpoint. The make generate-swagger-doc makefile target can regenerate the documentation JSON file.
You can run examples against the API using the Swagger tool. Another easy option is to use curl. I included two examples, one for a match and one for no match, they are named run-example and run-example-no-result respectively .
Here is what you should see when you run make run-example:
% make run-example
curl -i -X POST "http://localhost:3000/api/v1/rates/find" \
-H "accept: application/json" -H "Content-Type: application/json" -d \
"{ \"start_time\": \"2015-07-01T07:00:00-05:00\", \"end_time\": \"2015-07-01T12:00:00-05:00\"}"
HTTP/1.1 200 OK
Content-Type: application/json; charset=utf-8
ETag: W/"87820f968fa7488d92c1883e8d01ab65"
Cache-Control: max-age=0, private, must-revalidate
X-Request-Id: e7b39d7e-c795-4017-a372-b97abcec83d0
X-Runtime: 0.009540
Transfer-Encoding: chunked
{"result":1750,"msg":null}%