Awesome
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 = new Appbase({
url: HOST_URL,
app: APPNAME,
credentials: CREDENTIALS
});
appbase.index({
type: "product",
id: "1",
body: {
name: "A green door",
price: 12.50,
tags: ["home", "green"],
stores: ["Walmart", "Target"]
}
}).on("data", function(res) {
console.log(res);
}).on("error", function(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"
}).on("data", function(res) {
// "data" handler is triggered every time there is a **new** document update.
console.log(res);
}).on("error", function(err) {
console.log("caught a stream error", err);
})
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 a stream.Readable
object, which can be conveniently listened via the on("data")
event listener. Check out the stream_document_test.js where we make an update to the document and see any further updates to it via the "data" event.
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: {}
}
}
}).on("data", function(res, err) {
console.log(res);
}).on("error", function(err) {
console.log("caught a stream error", err);
})
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 a stream.Readable
object, which can be conveniently listened via the on("data")
event listener. Check out the stream_search_test.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: Ausername:password
combination 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
Get continuous updates on a JSON document with a type
and id
. 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
Get continuous updates on search queries (fuzzy, boolean, geolocation, range, full-text). 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)