google-maps-api-stream

A streaming, rate-limited, and caching interface to Google Maps APIs

npm install google-maps-api-stream --save

Usage

ES6 Syntax

import {Geocoding} from 'google-maps-api-stream';
 
const geocoder = new Geocoding({
  googleMaps: {
    key: 'your-api-key'
  },
  cacheFile: 'geocache.db'
});
 
geocoder.on('data', data => console.log(data));
geocoder.on('end', () => console.log('Done.'));
 
geocoder.write('Hamburg, Germany');
geocoder.write('Las Vegas');
geocoder.end();

ES5 Syntax

var mapsApi = require('google-maps-api-stream');
var Geocoding = mapsApi.Geocoding;
 
var geocoder = new Geocoding({
  googleMaps: {
    key: 'your-api-key'
  },
  cacheFile: 'geocache.db'
});
 
geocoder.on('data', data => console.log(data));
geocoder.on('end', () => console.log('Done.'));
 
geocoder.write('Hamburg, Germany');
geocoder.write('Las Vegas');
geocoder.end();

Further examples can be found in examples/

Response Format

All interfaces share the following response format:

{
  input: '', // input data, before the accessor was applied
  query: '', // input data, after the accessor was applied
  stats: {current: 1},
  response: ... // response format depends on the interface
  error: false,
  cached: false
}

API Documentation

All interfaces are NodeJS transform streams. Input data can be passed in by writing or piping to them. They emit the data, and end events. All interfaces accept an options object upon initialisation. The following options may be set:

options.googleMaps: Type: <Object>, default: {}. Options passed to the googlemaps module. You must set either a key property, containing a Google Maps API key, or a clientId and privateKey. Consult the googlemaps package documentation for other options.

options.queriesPerSecond: Type: <Number>, default: 35. Maximum number of queries per second.

options.cacheFile: Type: <String>, default: null. Path to a file for caching queries. A cache will not be used if this path is set to null.

options.accessor: Type: <Function>, default: function(data) { return data; }. This function can be used to transform data written to the stream before it is passed to the API.

options.stats: Type: <Object>, default: {current: 0}. A stats object which will be attached to every result. The value of stats.current is incremented with every query.

The Google Maps API stream module currently provides streaming interfaces to the following Google Maps APIs:

Directions

var directionsInterface = new mapsApi.Directions(options);

Required query parameters:

const query = {
  origin: 'address || lat,lng',
  destination: 'address || lat,lng'
};

Refer to Request Parameters for optional parameters.

Response format:
Google Directions Response

Geocoding

var geocoder = new mapsApi.Geocoding(options);

Required query parameters:

const query = {
  address: 'Some address, Sometown, Earth'
};

or

const query = 'Some address, Sometown, Earth';

Refer to Request Parameters for optional parameters.

Response format:
Google Geocoding Response

Reverse Geocoding

const query = {
  latlng: '53.5610771,9.9569145'
};

or

const query = {
  place_id: 'ChIJa76xwh5ymkcRW-WRjmtd6HU'
};

Refer to Request Parameters for optional parameters.

Response format:
Google Reverse Geocoding Response

Static Maps Images

Required query parameters:

const query = {
  center: 'lat,lng',
  zoom: number
  size: '{width}x{height}'
};

Refer to URL Parameters for optional parameters.

Response format:
A binary blob containing the static maps image

Static Maps URLs

Required query parameters:

const query = {
  center: 'lat,lng',
  zoom: number
  size: '{width}x{height}'
};

Refer to URL Parameters for optional parameters.

Response format:
A string containing the URL to the static maps image

Street View Images

Required query parameters:

const query = {
  location: '51.507868,-0.087689',
  size: '1200x1600'
};

or

const query = {
  pano: '<pano id>',
  size: '1200x1600'
};

Refer to URL Parameters for optional parameters.

Response format:
A binary blob containing the static maps image