<?php
 
// your code goes here
$str = 'Correct parameters and objects received raw message: {"message":{"message":"hi","chatBotID":6,"timestamp":1407393907},"user":{"firstName":"Tugger","lastName":"Sufani","gender":"m","externalID":"abc-639184572"}} apiSecret: 9HBkibOphng7w4p1ZdiiVJgzRI4kpD4Q Do the following two match? a702fc336f49b099764d35a548dd110fac2067bcd14a438676e4d579d70b6afc a702fc336f49b099764d35a548dd110fac2067bcd14a438676e4d579d70b6afc CORRECT MATCH! Array ( [message] => Array ( [message] => hi [chatBotID] => 6 [timestamp] => 1407393907 )';
$str .= '[user] => Array';
$str .= '   (';
$str .= '        [firstName] => Tugger';
$str .= '        [lastName] => Sufani';
$str .= '        [gender] => m';
$str .= '        [externalID] => abc-639184572';
$str .= '    )';
$str .= ') sent on Thu, 07 Aug 2014 2:45:07 am 6 seconds ago. (limit is 300) {"success":1,"errorMessage":"","message":{"chatBotName":"Desti","chatBotID":"6","message":"Yes, Tugger, I\'ve heard that one before.","emotion":"normal"}}';
preg_match('/(?<=success).*"message":"(.*?)"/', $str , $matches);
echo $matches[1];

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