Description

Weather forecast service

The service exposes two API endpoints:

• /v1/cities returns a list of cities, predefined by the admin in a configuration file
• /v1/cities/:id returns the corresponding city

Both accept a query param limit for limiting the forecasted days in the response, e.g: /v1/cities/:id?limit=5

Example of the response:

{
  "id": "603e45c0cf2c7cfe404cb0d9",
  "name": "Paris",
  "country": "FR",
  "lowTempLimit": 1,
  "forecast": [
    {
      "date": "2021-03-03T00:00:00.000Z",
      "minTemp": 7.94,
      "isLowExceeded": false
    },
    {
      "date": "2021-03-04T00:00:00.000Z",
      "minTemp": 7.51,
      "isLowExceeded": false
    },
    {
      "date": "2021-03-05T00:00:00.000Z",
      "minTemp": 3.04,
      "isLowExceeded": false
    },
    {
      "date": "2021-03-06T00:00:00.000Z",
      "minTemp": 0.92,
      "isLowExceeded": true
    },
    {
      "date": "2021-03-07T00:00:00.000Z",
      "minTemp": 0.91,
      "isLowExceeded": true
    }
  ]
}

• lowTempLimit: is the lower temperature limit specified by the admin in a configuration file
• date: the date when the weather is forecasted
• minTemp: the minimum temperature on the date in question
• isLowExceeded: a true or false value, indicating whether the temperature on that day exceeds lowTempLimit

Also the service supports Healthchecks by exposing /health endpoint to determine the status of the application.

Configuration

1. Check that Docker and Docker CLI are installed

2. Copy the content of of .env.example to .env by running the following command:

cp .env.example .env

3. Obtain an API key from OpenWeather

4. Fill in the missing variables in .env file

Note: the application will not run if the values provided in .env don't match the described patterns in the .env.example file

Installation

$ yarn

Running the app

1. Make sure that the port 3000 is not already allocated

2. Run the following command after configuring the application properly

# watch mode
$ docker-compose up

3. From your browser go to http://localhost:3000/v1/cities to see the forecast of the specified cities in the next five days

   • Alternatively you can use Postman for testing the API

4. The service fetches from Open Weather the forecast automatically when the interval specified in .env passes

Testing

# run tests
$ yarn test