I want to modify the xml or json request body using Javascript.

Google Cloud Apigee
1

Hi All,

I have a usecase where I need to send an HTTP request with an XML or JSON body. In the API Proxy, I would like to add an element (sum of two other elements) and then obtain the modified body.

My XML request is:

<?xml version="1.0" encoding="utf-8"?>
<Add>
 <a>10</a>
 <b>20</b>
 <c>Total</c>
</Add>

My JSON request is:

{
   "Add": {
      "a": "10",
      "b": "20",
      "c": "Total"
   }
}

JavaScript code for adding two elements a and b:

var a=context.getVariable("request.body.Add.a");
var b=context.getVariable("request.body.Add.b");
//var a=context.getVariable("request.queryparam.a.N");
print("a"+a);
print("b"+b);
var Total = parseInt(a) + parseInt(b);
context.setVariable("request.body.c",Total);

In Trace tool i’m getting 200 as a response but unable to get proper output :

Output from all Transactions:

anull
bnull

Postman response Is :

{
  "args": {}, 
  "data": "<?xml version=\"1.0\" encoding=\"utf-8\"?>\n<Add>\n <a>10</a>\n <b>20</b>\n <c>Total</c>\n</Add>\n", 
  "files": {}, 
  "form": {}, 
  "headers": {
    "Accept": "*/*", 
    "Accept-Encoding": "gzip, deflate", 
    "Cache-Control": "no-cache", 
    "Content-Length": "88", 
    "Content-Type": "application/xml", 
    "Host": "httpbin.org", 
    "Postman-Token": "690d3cd0-de25-44af-9451-8aec1945c2", 
    "User-Agent": "PostmanRuntime/6.4.1"
  }, 
  "json": null, 
  "origin": "114.79.146.115, 104.154.179.1, 114.79.146.115", 
  "url": "https://httpbin.org/post"
}

Could someone please help me?

Any Advice what i’m doing wrong here?

Thanks and Regards

Govind Verma

2

Hi @Govind Verma

You first need to access the request as JSON, then perform the calculations.

See the JavaScript object model docs for more details.

For JSON request if you use:

{
   "Add": {
      "a": 10,
      "b": 21,
      "c": "Total"
   }
}

Then the JavaScript policy, placed in the response flow of a no-route proxy, could be as simple as:

var body = request.content.asJSON;
body.Add.c = body.Add.a + body.Add.b;
response.content.asJSON = body;

I’ll leave it to you to deal with XML vs JSON.

Hope that helps

1 Like
3

Thanks for your reply @Kurt Googler Kanaskie,

But unfortunately it’s not working and throws 500 error message.

Any Advice what i’m doing wrong?

@Anil Sagar @ Google, @Dino-at-Google,@Brendan, @deboraelkin,@Siddharth Barahalikar,@Priyadarshi Ajitav Jena,@Robert Johnson,@Nisha Mallesh,@Anil Sagar,@sudheendras,@Mukundha Madhavan,@Jeremy Whitlock,@Nagashree B

4

Govind what is the error you are getting while using Kurt’s answer?

It should work, I used same code with some modification, try this,

var body = request.content.asJSON;
body.Add.c = body.Add.a + body.Add.b;
context.setVariable("total",JSON.stringify(body.Add.c));
5

Thanks @Siddharth Barahalikar for your reply, I got my answer.