Introduction

HTTP/WebSocket Client (JavaScript) for Enapso Enterprise Server.

Installation

npm install --save enapso-client-js

Getting Started

For this example we will use a production installation of the Enapso Enterprise Server, this is the Enapso Dash platform. The library use ES6 Promise based APIs.

1. Creating connection instance:

// HTTP connection
const HttpClient = require('enapso-client-js').HttpClient;
const conn = new HttpClient({
  url: 'https://dash.innotrade.com/http',
  username: 'guest',
  password: 'guest'
});

// WebSocket connection
const WebSocketClient = require('enapso-client-js').WebSocketClient
const conn = new WebSocketClient({
  url: 'wss://heprdlxdemo01.innotrade.com', // your remote Enapso server instance
  username: 'guest',
  password: 'guest'
});

2. Opening connection and login:

conn.open().then(() => {
  return conn.login();
}).then(() => {
  // here authenticated ...
}).catch(console.error);

2. Making requests to the server:

conn.send({
  ns: 'com.enapso.plugins.ontology',
  type: 'runSPARQLQuery',
  ontologyAlias: 'EnapsoUnits',
  query: 'SELECT ?v WHERE {?s ?p ?v} LIMIT 5',
  reasoning: false
}).then(console.log).catch(console.error);

3. Logout and close connection

conn.logout().then(() => {
  return conn.close();
}).then(() => {
  // here closed ...
}).catch(console.error);

4. Join all together using a more elegant way, the co library:

const co = require('co');
const HttpClient = require('enapso-client-js').HttpClient;
const conn = new HttpClient({
  url: 'https://dash.innotrade.com/http',
  username: 'guest',
  password: 'guest'
});

co(function *(){
  // opening connection
  yield conn.open();
  // login
  yield conn.login();
  // making request
  let response = yield conn.send({
    ns: 'com.enapso.plugins.ontology',
    type: 'runSPARQLQuery',
    ontologyAlias: 'EnapsoUnits',
    query: 'SELECT ?v WHERE {?s ?p ?v} LIMIT 5',
    reasoning: false
  });
  console.log(response);
  // logout
  yield conn.logout();
  // close connection
  yield conn.close();
}).catch(console.error);

Config params

let config = {};
config.url = 'https://dash.innotrade.com/http'; // the Enapso Enterprise Server connection URL
config.username = 'guest'; // login username
config.password = 'guest'; // login password
config.autoSyncTimeout = 500; // timeout used by the HttpClient to automatically pull messages from the server. Min value: 400ms

API

getId: Get the connection id value. CAUTION: this value should be kept secret.

conn.getId(); // UUID v4 value

getConfig: Get the configuration object passed to the client during initialization.

conn.getConfig();

open: Open the client connection.

conn.open().then(() => { console.log('connected!'); });

login: Login the client connection. Optionally username, password arguments can be passed to override the ones in the configuration. The response argument contains the user authorities/rights.

conn.login().then((response) => { console.log('authenticated!'); });

send: Send a request message to the server.

conn.send({{
  ns: 'com.enapso.plugins.ontology',
  type: 'runSPARQLQuery',
  ontologyAlias: 'EnapsoUnits',
  query: 'SELECT ?v WHERE {?s ?p ?v} LIMIT 5',
  reasoning: false
}}).then((response) => {});

sync: (Only available on HttpClient) Pull pending messages from the server and trigger the 'message' event if applicable. CAUTION: This feature is internally executed by the HTTP client on periodic intervals. See 'autoSyncTimeout' configuration property.

conn.sync().then((messages) => {});

getStatus: Get the client status: UP, DOWN

conn.getStatus();

logout: Logout the client connection.

conn.logout().then(() => { console.log('logged out!'); });

close: Close the client connection.

conn.close().then(() => { console.log('closed!'); });

Triggered events

conn.on('message', (msg) => {
  // triggered when a new message arrives from the server
  // argument msg is a JSON object
});

Tests

$ git clone https://github.com/innotrade/enapso-client-js.git
$ cd enapso-client-js/
$ npm install
$ npm test