yr.no-interface

HTTP request wrapper for the yr.no/api.met.no weather service API with support for streams.

Install

npm install yr.no-interface --save

Examples

All of these are in the /examples folder of this project.

Callback Example

const yrno = require('yr.no-interface')({
  request: {
    timeout: 25000
  }
});

yrno.locationforecast({
  query: {
    // Get weather for Dublin, Ireland
    lat: 53.3478,
    lon: 6.2597
  },

  // The locationforecast API version to call
  version: 1.9
}, function (err, xml) {
  if (err) {
    // Something went wrong...
  } else {
    // We got an XML response!
  }
});

Streaming Example

Streams are one of the most powerful features in node.js. They allow you to perform I/O while using a tiny amount of memory since they pass data through the process in small "chunks".

Using streams is useful for certain response types such as the radar API since it returns a large GIF file that could use a large amount of the node.js process memory if loaded into a callback

Below we use a stream to pipe the HTTP respone from the yr.no API to a file on our machine.

const fs = require('fs');
const path = require('path');
const yrno = require('yr.no-interface')({
  request: {
    timeout: 25000
  }
});

// response data will be written to a file called res.xml in the
// directory this script is being run from
const filepath = path.join(process.cwd(), 'weather.xml');

yrno.locationforecast({
  query: {
    lat: 53.3478,
    lon: 6.2597
  },
  version: 1.9
})
  .pipe(fs.createWriteStream(filepath));

Promises Example

This module does not support promises by default. Here's how you could get Promise support:

const Promise = require('bluebird');

// Now all functions will return promises. Can also use a module like "pify"
const yrno = Promise.promisifyAll(
  require('yr.no-interface')({
    request: {
      timeout: 25000
    }
  })
);

// Note the "Async" added to use teh promise version
yrno.locationforecastAsync({
  query: {
    lat: 53.3478,
    lon: 6.2597
  },
  version: 1.9
})
   .then((xml) => {
    console.log('weather xml is - ', xml);
  })

API

module

This module exports a single function that must be called to get an API wrapper.

// Get an API wrapper instance with a default request timeout of 25 seconds
const yrno = require('yr.no-interface')({
  request: {
    // Can pass anything supported by the request module here.
    // Passing "qs" or "url" will fail since the module will overwrite them
    timeout: 25000
  }
});

Returns an API instance.

instance

An instance is an object with functions attached. The functions are listed below.

instance.FUNCTION

All functions on an instance contain the same signature of yrno.func([params[, callback]), e.g yrno.locationforecast(params, callback).

callback is optional. If no callback is provided a stream is returned so you can use node's stream awesomeness to pass data around. params should contain the querystring params as specified at the yr.no docs.

Each request must specify params.version as the met.no API requires this.

instance functions

errornotifications
extremeforecast
extremesWWC
forestfireindex
geosatellite
gribfiles
icemap
locationforecast
locationforecastlts
metgm
mountaineasterobservations
oceanforecast
polarsatellite
probabilityforecast
radar
seaapproachforecast
seasonforecast
subjectiveforecast
sunrise
temperatureverification
textforecast
textlocation
tidalwater
trondheimsleia
turbulence
uvforecast
weatherformetnosite
weathericon
windforecast

ktrance/yr.no-interface