Calling API from Saleforce is giving error code 500 - rest

Question

I have a REST API to callout from Salesforce.
The authorization of the API is through access token.
I am able to get the access token through POST request in Salesforce. Also tested from Postman through that token and able to get a successful response.
I am using the below code to callout the API using the access token:
String endpoint_x = '*****';//Putting my endpoint here
Http httpObject;
HttpResponse response;
String accessToken;
accessToken = MyUtilityClass.getAccessToken();
jsonBody = json.serializePretty('', true);//Yes, My JSON is empty
HttpRequest request = new HttpRequest();
request.setEndpoint(endpoint_x);
request.setHeader('Authorization', 'Bearer '+accessToken);
request.setMethod('POST');
request.setBody(jsonBody);
httpObject = new Http();
response = httpObject.send(request);
System.debug('Response=' + response);
Getting Response value as below:
System.HttpResponse[Status=Internal Server Error, StatusCode=500]
I have tried putting '{}' in the Jsonbody. Added 'Content-Type' in header but nothing worked.
Where should I lookout for this?

Answer 1

In the Postman, I was not putting anything in the body, and getting a successful response.
To get the same behaviour, I was using empty string in Apex, like this:
jsonBody = json.serializePretty('', true);
But the parser was not working correctly.
To solve this, I created a class without any field:
class ClassForEmptyBody{
}
And used object of that class in the serializer:
ClassForEmptyBody classForEmptyBodyObject = new ClassForEmptyBody();
jsonBody = json.serializePretty(classForEmptyBodyObject , true);

Answer 2

Why are you passing json body if nothing is in there. Just skip setbody code and try.