extract an object from from a JSON response in nodeJs

Question

I am receiving a message from a WebSocket like so

ws.onmessage = (e) => {
       debugger
       if (e.data.startsWith('MESSAGE'))
           alert(JSON.stringify(e.data))
       ImageReceived(e.data)
       console.log(JSON.stringify(e.data))
   }

the message, However, is received correctly, but I am having some difficulties in extracting the content I desire from the message. The message looks as follows, and I want to extract this part from the message :

{"physicalPath":"E:\\NORMAL\\person.jpeg","status":"Normal","version":47,"issuer":"gmail.com","id":32631}

and the message is structured as follows

"MESSAGE
expires:1607105481567
destination:/queue/[email protected]
_type:com.model.Image
priority:9
message-id:ID:LA99343812-1:1:1:1:20
persistent:true
timestamp:1607105445567

{"physicalPath":"E:\\NORMAL\\person.jpeg","status":"Normal","version":47,"issuer":"gmail.com","id":32631}"

thank you very much, this worked. but it leads to the next question :) . — Fadi
– Fadi, Commented Dec 4, 2020 at 20:21
how can I extract the individual attribultes, e.g. I want to get only the physicalPath attribute, do you have an idea about how to get? — Fadi
– Fadi, Commented Dec 4, 2020 at 20:22

Đinh Carabus · Accepted Answer · 2020-12-04 20:37:02Z

1

In response to your last comment: You could try to parse the extracted string into an actual object

var data = JSON.parse(e.data.match(/{[^}]*}/)[0]);

alternatively (data is not valid JSON)

var data = new Function("", "return " + e.data.match(/{[^}]*}/)[0])()

then you can access the individual properties like this

data.physicalPath

edited Dec 4, 2020 at 20:37

answered Dec 4, 2020 at 20:25

Đinh Carabus

3,5054 gold badges26 silver badges47 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

Fadi Over a year ago

this returns :1 Uncaught SyntaxError: Unexpected token u in JSON at position 0

Fadi Over a year ago

maybe because the JSON is not a valid JSON?

Đinh Carabus Over a year ago

@Fadi Yeah, try the alernative version (I just updated my answer).

Collectives™ on Stack Overflow

extract an object from from a JSON response in nodeJs

1 Answer 1

3 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

3 Comments

Your Answer

Sign up or log in

Post as a guest

Related