att-dhs/js/att.dhs.longpoller.js

AT&T Developer Hosted Server Library

/*jslint browser: true, devel: true, node: true, debug: true, todo: true, indent: 2, maxlen: 150, unparam: true*/
/*global require, exports*/

'use strict';

var config = require('./att.dhs.config').config,
  restify = require('restify'),
  clients = {};

function getRestClient(token) {
  var restClient,
    logger = config.getLogger();

  logger.logInfo('dhs.longpoller: getRestClient');
  logger.logTrace('token', token);

  restClient = restify.createJsonClient({
    url: 'https://api.att.com/',
    userAgent: 'att-dhs',
    accept: 'application/json',
    connection: 'keep-alive',
    DTN: '1',
    headers: {
      Authorization: 'Bearer ' + token
    },
    requestTimeout: 10 * 60 * 1000,
    timeout: 5 * 60 * 300
  });

  return restClient;
}

function deleteClient(sessionId) {
  var logger = config.getLogger(),
    restClient;

  logger.logInfo('dhs.longpoller: deleteClient');
  logger.logTrace('Session Id', sessionId);

  if (clients[sessionId] === undefined) {
    return;
  }

  restClient = getRestClient(clients[sessionId].token);

  logger.logDebug('Deleting Client');
  logger.logTrace('Session Id', sessionId);

  if (clients.hasOwnProperty(sessionId)) {
    delete clients[sessionId];

    restClient.del('RTC/v1/sessions/' + sessionId, function (error, req, res, result) {
      logger.logDebug('Client Deleted');
      logger.logTrace('Delete result', result);
    });
  }
}
//
//function requestPolling(sessionId) {
//  var restClient,
//    logger = config.getConfiguration().logger;
//
//  logger.logInfo('dhs.longpoller: requestPolling');
//  logger.logTrace('Session Id', sessionId);
//
//  restClient = getRestClient(clients[sessionId].token);
//  restClient.get('RTC/v1/sessions/' + sessionId + '/events', function (error, req, res, result) {
//    if (undefined !== error
//        && null !== error) {
//      options.error(error);
//      return;
//    }
//
//    options.success(result, res);
//  });
//}
//
//function onStartClientSuccess(result, res) {
//  var logger = config.getConfiguration().logger;
//
//  logger.logInfo('dhs.longpoller: onStartClientSuccess');
//  logger.logTrace('statusCode', res.statusCode);
//
//  if (res.statusCode == 204) {
//    logger.logInfo('Started Client Successfully');
//    logger.logDebug('Success: no data');
//  }
//
//  if (res.statusCode == 200) {
//    logger.logInfo('Started Client Successfully');
//    logger.logDebug('Success: with data');
//    logger.logTrace('Success Data', result);
//
//    if (Object.keys(result).length > 0) {
//      result.events.eventList.forEach(function (element) {
//        try {
//          socket.sendData('event', element);
//        } catch (e) {
//          logger.logInfo('Error starting client');
//          logger.logError(e);
//          // issue with the websocket connection; stop polling
//          deleteClient(sessionId);
//        }
//      });
//    }
//  }
//
//  if (clients[sessionId] !== undefined) {
//    requestPolling(sessionId, token);
//  }
//
//  logger.logDebug('WebSocket :Success');
//}
//
//function onStartClientError(error) {
//  var logger = config.getConfiguration().logger;
//
//  logger.logInfo('dhs.longpoller: onStartClientError');
//  logger.logTrace(error.statusCode);
//  logger.logError(error);
//
//  if (error.statusCode === 401 /* Unauthorized Request */
//      || error.statusCode === 403 /* Session Id not associated with token */
//      || error.statusCode === 404 /* Session is expired */) {
//    try {
//      // attempt to send data, but recover if unable to
//      socket.sendData('error', error);
//    } catch (e) {
//      logger.logInfo('Error message not sent');
//      logger.logError(e);
//    }
//  } else {
//    //Retry polling again
//    if (clients[sessionId] !== undefined) {
//      requestPolling(sessionId);
//    }
//  }
//}

function startClient(data, socket) {
  var options,
    sessionId,
    token,
    requestPolling,
    count,
    restClient,
    logger = config.getLogger();

  logger.logInfo('dhs.longpoller: startClient');
  logger.logTrace('data', data);

  options = {};
  count = 0;
  sessionId = data.sessionId;
  token = data.token;

  requestPolling = function () {
    logger.logInfo('dhs.longpoller.startClient: requestPolling');
    logger.logTrace('Session ID', sessionId);

    restClient.get('RTC/v1/sessions/' + sessionId + '/events',
      function (error, req, res, result) {
        if (undefined !== error
            && null !== error) {
          options.error(error);
          return;
        }

        options.success(result, res);
      });
  };

  options.onTimeout = function (result) {
    requestPolling(); // if timeout do a long polling
  };

  options.success = function (result, res) {
    count = count + 1;

    logger.logInfo('dhs.longpoller.startClient: success');
    logger.logTrace('Result', result);
    logger.logTrace('Status Code', res.statusCode);

    if (res.statusCode === 204) {
      logger.logDebug('success: no data');
    }

    if (res.statusCode === 200) {
      logger.logDebug('success: with data');

      if (Object.keys(result).length > 0) {
        result.events.eventList.forEach(function (element) {
          try {
            socket.sendData('event', element);
          } catch (e) {
            logger.logDebug('Error while sending message');
            logger.logError(e);

            deleteClient(sessionId); // issue with the websocket connection; stop polling
          }
        });
      }
    }

    if (undefined !== clients[sessionId]) {
      requestPolling();
    }

    logger.logDebug('webSocket: Success');
  };

  options.error = function (error) {
    logger.logInfo('dhs.longpoller.startClient: error');
    logger.logTrace('Error object', error);

    /**
     * 401: Unauthorized Request
     * 403: Session Id not associated with token
     * 404: Session has expired
     */
    if (error.statusCode === 401 || error.statusCode === 403 || error.statusCode === 404) {
      try {
        socket.sendData('error', error); // Attempt to send data, but recover if unable to
      } catch (e) {
        logger.logDebug('Error while sending message');
        logger.logError(e);
      }
    } else {
      if (clients[sessionId] !== undefined) {
        requestPolling(); // Retry polling again
      }
    }

    logger.logDebug('webSocket: Error');
  };

  restClient = getRestClient(token);

  clients[data.sessionId] = socket; // Saving the client before requesting
  logger.logTrace('Count of connected clients', Object.keys(clients).length);

  requestPolling();
}

exports.longPoller = {
  startClient: startClient,
  deleteClient: deleteClient
};