Update app.js

@@ -85,11 +85,12 @@ async function handleEvent(event) {
   }
   else if (event.type == 'message'&& event.message.type == 'image') {
     return new Promise(async(resolve,reject)=>{  
-
+      var file;
       client.getMessageContent(event.message.id)
       .then((stream) => {
         stream.on('data', (chunk) => {
-          fs.writeFileSync('./photo/1.png',chunk);       
+          fs.writeFileSync('/photo/1.png',chunk);
+               file=chunk;
         });
       });
       
@@ -106,7 +107,7 @@ async function handleEvent(event) {
           'Content-Type': 'application/json',
           'Ocp-Apim-Subscription-Key': '979dc5d63344438fa4701c62feebb7dc'
         },
-      body: chunk
+      body: file
       };
       console.log(body);
       request.post(options, function (error, response, body) {