fling/lib/transport.sender.http.js

JSON Fling is a simple JSON-RPC framework for NodeJS with built-in permissions and support for different transports.

"use strict";

var AbstractSenderTransport = require( './transport.receiver.abstract' );
var request = require( 'request' );

var requestIds = 0;

var ExpressSenderTransport = function( config ) {
	AbstractSenderTransport.apply( this, arguments );

	this._url = this._config.url;
	this._ca = this._config.ca || null;
	this._headers = this._config.headers || null;

};
require( 'util' ).inherits( ExpressSenderTransport, AbstractSenderTransport );

ExpressSenderTransport.prototype.call = function( method, params, headers, done ) {

	if ( typeof headers === 'function' ) {
		done = headers;
		headers = null;
	}

	if ( !method ) {
		done( {
			code:    400,
			message: 'method is required',
			data:    null
		} );
		return;
	}

	if ( typeof params === 'function' ) {
		done = params;
		params = null;
	}

	var id = ++requestIds;

	var requestPayload = {
		jsonrpc: '2.0',
		id:      id,
		method:  method,
		params:  params
	};

	var query = {
		uri:                this._url,
		method:             'POST',
		rejectUnauthorized: false,
		requestCert:        true,
		agent:              false,
		json:               requestPayload
	};

	if ( this._ca ) {
		query.ca = this._ca;
	}

	if ( this._headers ) {
		query.headers = this._headers;
	}

	if ( headers && typeof headers === 'object' ) {

		if ( !query.headers ) {
			query.headers = {};
		}

		for ( var field in headers ) {
			if ( headers.hasOwnProperty( field ) ) {
				query.headers[ field ] = headers[ field ];
			}
		}
	}

	request( query, function( err, response, body ) {

		if ( !err ) {

			if ( !body ) {
				err = 'no response payload';
			} else if ( !body.hasOwnProperty( 'result' ) && !body.hasOwnProperty( 'error' ) ) {
				err = 'no response result or error';
			}

		}

		var errObj = null;

		if ( err ) {

			errObj = new Error( 'transport error' );
			errObj.code = 500;
			errObj.data = err.message;

			done( errObj );

		} else if ( body.error ) {

			errObj = new Error( body.error.message );
			errObj.code = body.error.code;
			errObj.data = body.error.data;

			done( errObj );

		} else {
			done( null, body.result );
		}

	} );

	return id;

};

module.exports = ExpressSenderTransport;