appbase-js

appbase-js

Appbase.io streaming client lib for Node.JS and Javascript (browser builds in /browser/), can be used with elasticsearch.js.

Quick Example

Working code snippets where each step builds on the previous ones.

Step 1: Add some data into the app (uses elasticsearch.js)

// app and authentication configurations 
const HOSTNAME = "scalr.api.appbase.io"
const APPNAME = "createnewtestapp01"
const USERNAME = "RIvfxo1u1"
const PASSWORD = "dee8ee52-8b75-4b5b-be4f-9df3c364f59f"

// Add data into our ES "app index"
var elasticsearch = require('elasticsearch')
var client = new elasticsearch.Client({
			host: 'https://'+USERNAME+":"+PASSWORD+"@"+HOSTNAME,
			apiVersion: '1.6'
		});
client.index({
    index: APPNAME,
    type: "product",
    id: "1",
    body: {
        name: 'A green door',
        price: 12.50,
        tags: ['home', 'green'],
        stores: ['Walmart', 'Target']
    }
}, function(err, res) {
    if (!err)
      console.log(res);
});

Step 2: Stream the Document Updates

var appbase = require('appbase-js')
var streamingClient = appbase.newClient({
      url: 'https://'+HOSTNAME,
      appname: APPNAME,
      username: USERNAME,
      password: PASSWORD
});
streamingClient.streamDocument({
      type: 'product',
      id: '1'
}).on('data', function(res) {
      // client would emit "data" event every time there is a document update.
      console.log(res)
}).on('error', function(err) {
      console.log(err)
      return
})

Console Output

{ _index: 'app`248',
  _type: 'product',
  _id: '1',
  _version: 4,
  found: true,
  _source: 
   { name: 'A green door',
     price: 12.5,
     tags: [ 'home', 'green' ],
     stores: [ 'Walmart', 'Target' ] } }

streamDocument() returns a stream.Readable object, which can be conveniently listened via the 'on("data")' event listener. Check out the get_test.js where we make an update to the document and see it stream.

Step 3: Streaming Queries

While streaming documents is straightforward, streaming queries touch the entire breadth of ElasticSearch Query DSL - boolean, regex, geo, fuzzy to name a few. We will stream the results of a simple match_all query on the product type:

streamingClient.streamSearch({
	type: 'product',
	body: {
		query: {
			match_all: {}
		}
	}
}).on('data', function(res, err) {
	console.log(res);
}).on('error', function(err) {
	console.log("caught a stream error", err)
	return
})

Console Output

{ took: 1,
  timed_out: false,
  _shards: { total: 1, successful: 1, failed: 0 },
  hits: 
   { total: 4,
     max_score: 1,
     hits: [ [Object], [Object], [Object], [Object] ] } }

streamSearch() also returns a stream.Readable object, which can be conveniently listened via the 'on("data")' event listener. Check out the search_test.js where we make an update that matches the query and see it stream.

API Reference

Global

appbase.newClient(args)

Returns a client object on which streaming requests can be performed.

args - A set of key/value pairs that configures the ElasticSearch Index
    url: "https://scalr.api.appbase.io"
    appname: App name (equivalent to an ElasticSearch Index)
    username: App's username
    password: App's password key

Client

client.streamDocument(args)

Get all the document changes as a stream. Returns a stream.Readable object.

args - A set of key/value pairs that makes the document URL
    type: ElasticSearch Type, a string
    id: Valid Document ID

client.streamSearch(args)

Get all the query results as a stream. Returns a stream.Readable object.

args - A set of key/value pairs that makes the document URL
    type: ElasticSearch Type, a string
    body: A JSON Query Body (Any query matching the ElasticSearch Query DSL)