This application is meant to be a black-box data api to provide data at various time-delays. It is not meant to show good practice!

This application was built to use minimal dependencies. The only dependencies should be installable through NPM. I wrote the application with node version 8.9.4 and npm 5.6.0 which should be fine despite them not being the latest versions. I didn't do anything crazy with the javascript. I left out typescript to keep things simple.

To install the application, just navigate to the directory with the package.json file and run:

npm install

This should install the application. You can then run the server using:

npm run start

I also included a testing framework in case you want to do anything with that. Run the tests with:

npm run test

The "database" for this application is really just a few JSON files which are never modified. This way, the server database is refreshed on every restart. Instead, the "database" service maintains live in-memory references to the JSON which is loaded and parsed on startup. All API actions work with these in-memory references to appear to function like a real database without us having to install one.

Application configuration can be found in the config/development.json file. Currently there are two properties. app.port determines what port the application listens on, and db.maxDelay determines the maximum delay in milliseconds that the system might wait for before responding. The database system waits a random amount of time from 0 to db.maxDelay milliseconds before responding.

The websocket system is designed to mimic an RPC-like format. Open a websocket to localhost:3000 and send stringified JSON messages with the following format:

{
    "entityType": "user | project",
    "userId": 0,
    "projectId": 0
    "action": "one of the below actions",
    "data": {
        "arguments": "to the command as JSON"
    }
}

Responses: The websocket system will respond to commands in the following format:

{
    "type": "userActionResponse | projectActionResponse",
    "result": {
        "JSON response": "from the server"
    }
}

Available Actions for commands

USERS:
getAll
getById
create
update
delete

PROJECTS:
getAll
getById
getByUserId
create
update
delete

EXAMPLE COMMAND: Update user's first name to Harold. Will log "{ type: 'userActionResponse', result: { message: 'User updated successfully' } }" when complete.

var websocket = new WebSocket('ws://localhost:3000');
websocket.onmessage = (message) => { console.log(JSON.parse(message.data)); };
websocket.send(JSON.stringify({
    "entityType": "user",
    "userId": 3,
    "action": "update",
    "data": {
        "fname": "Harold"
    }
}));