test-assignment-parcellab/src/integration/weather/openmeteo.ts

import fetch from 'node-fetch';
import PQueue from 'p-queue';
import { WeatherProvider } from './types';

const requestedFields = [
    'temperature_2m',
    'relativehumidity_2m',
    'apparent_temperature',
    'is_day',
    'precipitation',
    'rain',
    'showers',
    'snowfall',
    'weathercode',
    'cloudcover',
    'pressure_msl',
    'surface_pressure',
    'windspeed_10m',
    'winddirection_10m',
    'windgusts_10m',
] as const;

type OpenmeteoKey = (typeof requestedFields)[number];
type OpenmeteoResponse =
    | {
          current_units?: Record<OpenmeteoKey, string | undefined>;
          current?: Record<OpenmeteoKey, string | number | undefined>;
      }
    | undefined;

export const createOpenmeteoClient = (): WeatherProvider => {
    // Rate limit (according to https://open-meteo.com/en/terms it's 10k per day;
    // here we set it 1 per second, should be enough for the demo app goal)
    const queue = new PQueue({
        interval: 1000,
        intervalCap: 1,
        timeout: 2000,
        throwOnTimeout: true,
    });

    return {
        getCurrentWeather: async ({ latitude, longitude }) =>
            queue.add(async () => {
                const response = await fetch(
                    `https://api.open-meteo.com/v1/forecast?latitude=${latitude}&longitude=${longitude}&current=${requestedFields.join(
                        ',',
                    )}`,
                );
                const body = (await response.json()) as OpenmeteoResponse;
                if (!body || !body.current || !body.current_units) {
                    throw new Error('cannot load weather');
                }

                const { current, current_units } = body;
                const getReadableValue = (key: OpenmeteoKey) =>
                    `${current[key]}${current_units[key]}`;

                return {
                    temperature: getReadableValue('temperature_2m'),
                    apparentTemperature: getReadableValue(
                        'apparent_temperature',
                    ),
                    relativeHumidity: getReadableValue('relativehumidity_2m'),
                    //...
                };
            }),
    };
};