appbase-js
Appbase.io is a data streams library for Node.JS and Javascript (browser UMD build is in the dist/ directory); compatible with elasticsearch.js.
An up-to-date documentation for Node.JS API is available at http://docs.appbase.io/javascript/quickstart.html.
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 HOST_URL = "https://scalr.api.appbase.io";
const APPNAME = "createnewtestapp01";
const CREDENTIALS = "RIvfxo1u1:dee8ee52-8b75-4b5b-be4f-9df3c364f59f";
// Add data into our ES "app index"
var Appbase = require("appbase-js");
var appbase = Appbase({
url: HOST_URL,
app: APPNAME,
credentials: CREDENTIALS
});
appbase
.index({
type: "product",
id: "1",
body: {
name: "A green door",
price: 12.5,
tags: ["home", "green"],
stores: ["Walmart", "Target"]
}
})
.then(res => {
console.log(res);
})
.catch(err => {
console.log(err);
});Step 2: Read the data stream from a particular DB location
Returns continous updates on a JSON document from a particular type.
appbase.getStream(
{
type: "product",
id: "1"
},
data => {
// "data" handler is triggered every time there is a **new** document update.
console.log(data);
},
error => {
console.log("caught a stream error", error);
}
);Note: Existing document value is returned via get() method.
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" ]
}
}getStream() returns an object which has stop & reconnect properties. Check out the getStreamTest.js where we make an update to the document and see any further updates to it via the "data" callback.
Step 3: Apply queries on data streams
Get continuous results by searching across the database streams. A query can be written using the ElasticSearch Query DSL - which supports composing boolean, regex, geo, fuzzy, range queries. Let's stream the results of a simple match_all query on the product type:
appbase
.searchStream({
type: "product",
body: {
query: {
match_all: {}
}
}
},
data => {
console.log(data);
},
error => {
console.log("caught a stream error", error);
})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] ]
}
}searchStream() also returns an object, which can be conveniently listened via the onData callback. Check out the searchStreamTest.js where we make an update that matches the query and see the results in the event stream.
API Reference
For a complete API reference, check out JS API Ref doc.
Global
Returns a reference 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" app: App name (equivalent to an ElasticSearch Index) credentials: A
username:passwordcombination used for Basic Auth.
Optionally (and like in the quick example above), url can contain the credentials field in the format: https://<credentials>@scalr.appbase.io.
Reference
reference.getStream(args, onData, onError, onClose)
Get continuous updates on a JSON document with a type and id.Returns an object.
args - A set of key/value pairs that makes the document URL type: ElasticSearch Type, a string id: Valid Document ID
reference.searchStream(args, onData, onError, onClose)
Get continuous updates on search queries (fuzzy, boolean, geolocation, range, full-text).Returns an 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)