Shortest flight route

This application provides an API for searching the shortest routes between airports.

User Stories (Requirements)

• As a user I can make a GET request to an endpoint with an origin and destination query parameter, and receive back the shortest route between the two, as an array of connecting flights. A shortest route is defined as the route with the fewest connections. If there are mulitple routes with the same number of connections, you may choose any of them.
• As a user I am provided meaningful feedback should no route exist between the airports.
• As a user I am provided meaningful feedback if an error occurred with my request.

NOTE: THE SHORTEST PATH FUNCTIONALITY MAY NOT RELY ON AN EXTERNAL LIBRARY. YOU MUST DEVELOP THIS ON YOUR OWN.

Testing

Within the data folder you will find two subdirectories, test and full. test offers a small subset of the data found in full which you may use when developing your solution. Your final solution however must be performant with the full set.

Some test cases to consider on the test data set.

Origin	Destination	Expected Result
YYZ	JFK	YYZ -> JFK
YYZ	YVR	YYZ -> JFK -> LAX -> YVR
YYZ	ORD	No Route
XXX	ORD	Invalid Origin
ORD	XXX	Invalid Destination

Running and testing the app

Requirements

1. Docker
2. Docker compose
3. Go 1.12+

Building and executing

Open a terminal window, navigate to the source root and run the following command:

docker-compose up

This will spin up a MySQL container, populate the database, build the application and execute it.

To stop the application run the following command:

docker-compose down

It is also possible to execute the application alone, or targeting another db host or container, updating the config file and executing the application as follows:

docker build --tag sfp-api .
docker run -d sfp-api

Testing the app

The server listens on port 5000 by default. You can change this in config.toml file.

The app contains unit tests for the core logic. Those tests can be run from the source root path with:

go test ./...

Routes

All routes are prefixed using the prefix option in the server section of the config file.

GET /v1/routes

This route returns the shortest route between two airports if one exists.

Params

origin: (query) The route origin airport IATA 3 code destination: (query) The route destination airport IATA 3 code

Results

200 OK: Success

{"flights": [{"origin":"JFK","destination":"YYZ","airline":"AA"}]}

404 Not Found: No route exists

{"error":true,"message":"no route exists between origin and destination"}

422 Unprocessable Entity: Validation error

{"error":true,"message":"invalid origin"}

503 Service Unavailable: Other errors, like database connections, etc.

{"error":true,"message":"Service Unavailable"}

Configuration

Note: This application uses a single configuration file config.toml to run. Although there are secrets in the config file, kept there for simplicity in this project, this is not suitable for production. A better way of handling that is to use environment variables or a configuration service, storing only configuration keys in the config file.

The config file contains options for setting DB connection and server options.

The server also supports loading configuration values from environment variables, overriding the config file values. For example, it is possible to override the database password with an environment variable named API_DB_PASSWORD. It is also possible to change the server prefix with API_SERVER_PREFIX. This feature is available for all configuration options.

TODO: Improvements

• Add integration tests
• Add caching on services
• Add caching on API results