queue support in case of error during sending logs to loggly

-make buffer size configurable
-handle 403 error(bad token)
-retries to send buffered logs to loggly in every 5 sec
-queue support for bulk and input mode

lib/loggly/client.js

@@ -56,6 +56,7 @@ var Loggly = exports.Loggly = function (options) {
   this.userAgent    = 'node-loggly ' + loggly.version;
   this.useTagHeader = 'useTagHeader' in options ? options.useTagHeader : true;
   this.isBulk       = options.isBulk || false;
+  this.numberOfLogtobebuffered = options.numberOfLogtobebuffered || 1000;
   //
   // Set the tags on this instance.
   //
@@ -119,6 +120,7 @@ Loggly.prototype.log = function (msg, tags, callback) {
     body:    msg,
     proxy:   this.proxy,
     isBulk: this.isBulk,
+    numberOfLogtobebuffered: this.numberOfLogtobebuffered,
     headers: {
       host:             this.host,
       accept:           '*/*',

lib/loggly/common.js

@@ -13,6 +13,17 @@ var arrSize = 100,
     arrMsg = [],
     timerFunction = null;
 
+// 
+// Variables for buffer array 
+// 
+var arrBufferedMsg = [],
+    timerFunctionForBufferedLogs = null;
+
+// 
+// flag variable to validate authToken 
+//
+var isValidToken = true;
+
 var https = require('https'),
     util = require('util'),
     request = require('request'),
@@ -77,7 +88,8 @@ common.loggly = function () {
       auth,
       proxy,
       isBulk,
-      uri;
+      uri,
+      numberOfLogtobebuffered;
 
   //
   // Now that we've popped off the two callbacks
@@ -99,6 +111,7 @@ common.loggly = function () {
       isBulk      = args[0].isBulk;
       headers     = args[0].headers;
       proxy       = args[0].proxy;
+      numberOfLogtobebuffered = args[0].numberOfLogtobebuffered;
     }
   }
   else if (args.length === 2) {
@@ -113,6 +126,18 @@ common.loggly = function () {
   }
 
   function onError(err) {
+    if(!isValidToken){
+      console.log(err);
+      return;
+    }
+    var arrayLogs = [];
+    if(isBulk) {
+      arrayLogs = requestOptions.body.split('\n');
+    } else {
+      arrayLogs.push(requestOptions.body);
+    }
+    storeLogs(arrayLogs);
+
     if (!responded) {
       responded = true;
       if (callback) { callback(err) }
@@ -138,9 +163,11 @@ common.loggly = function () {
           return onError(err);
         }
         var statusCode = res.statusCode.toString();
+        if(statusCode === '403') isValidToken = false;
         if (Object.keys(failCodes).indexOf(statusCode) !== -1) {
           return onError((new Error('Loggly Error (' + statusCode + '): ' + failCodes[statusCode])));
-        }
+        } 
+        sendBufferdLogstoLoggly();
         success(res, body);
       });
     }
@@ -156,29 +183,26 @@ common.loggly = function () {
     // Join Array Message with new line ('\n') character
     //
     requestOptions.body = arrMsg.join('\n');
+    arrMsg.length = 0;
     try {
       request(requestOptions, function (err, res, body) {
         if (err) {
           return onError(err);
         }
         var statusCode = res.statusCode.toString();
+        if(statusCode === '403') isValidToken = false;
         if (Object.keys(failCodes).indexOf(statusCode) !== -1) {
           return onError((new Error('Loggly Error (' + statusCode + '): ' + failCodes[statusCode])));
         }
+        sendBufferdLogstoLoggly();
         success(res, body);
       });
     }
     catch (ex) {
       onError(ex);
     }
-    finally {
-      //
-      // Empty the array
-      //
-      arrMsg.length = 0;
-    }
   }
-  if (isBulk === true) {
+  if (isBulk && isValidToken) {
     if (timerFunction === null) {
       timerFunction = setInterval(function () {
         sendBulkLogs();
@@ -189,9 +213,47 @@ common.loggly = function () {
       sendBulkLogs();
     }
   }
-  else {
+  else if(isValidToken) {
     sendLogs();
   }
+
+  //
+  // retries to send buffered logs to loggly in every 5 sec
+  //
+  if (timerFunctionForBufferedLogs === null) {
+    timerFunctionForBufferedLogs = setInterval(function () {
+      if (arrBufferedMsg.length) sendBufferdLogstoLoggly();
+    }, 5 * 1000);
+  }
+
+
+  function sendBufferdLogstoLoggly() {
+    var arrayMessage = [];
+    var bulkModeBunch = arrSize;
+    var inputModeBunch = 1;
+    var logsInBunch = isBulk ? bulkModeBunch : inputModeBunch;
+    for(var startIndex = 0; startIndex < arrBufferedMsg.length; startIndex = startIndex + logsInBunch) {
+      arrayMessage = arrBufferedMsg.slice(startIndex, startIndex + logsInBunch); 
+      requestOptions.body = isBulk ? arrayMessage.join('\n') : arrayMessage[0];
+      request(requestOptions, function (err, res, body) {
+        if(err) return;
+        var statusCode = res.statusCode.toString();
+        if(statusCode === "200"){
+          arrBufferedMsg.splice(0, logsInBunch);
+        }
+      });
+    }
+  }
+
+//
+// This function will store logs into buffer
+//
+  function storeLogs(logs) {
+    if (!logs.length) return;
+    var numberOfLogsToBeRemoved = (arrBufferedMsg.length + logs.length) - numberOfLogtobebuffered;
+    if (numberOfLogsToBeRemoved > 0) arrBufferedMsg = arrBufferedMsg.splice(numberOfLogsToBeRemoved);
+      arrBufferedMsg = arrBufferedMsg.concat(logs);
+    }
 };
 //
 // ### function serialize (obj, key)