Sending POST request in ESB mule for API

Question

I try to send the post request to API using ESB mule. Hence i have created flow like below.

     <?xml version="1.0" encoding="UTF-8"?>
<mule xmlns:json="http://www.mulesoft.org/schema/mule/json" xmlns:http="http://www.mulesoft.org/schema/mule/http" xmlns="http://www.mulesoft.org/schema/mule/core" xmlns:doc="http://www.mulesoft.org/schema/mule/documentation"
    xmlns:spring="http://www.springframework.org/schema/beans" 
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-current.xsd
http://www.mulesoft.org/schema/mule/core http://www.mulesoft.org/schema/mule/core/current/mule.xsd
http://www.mulesoft.org/schema/mule/http http://www.mulesoft.org/schema/mule/http/current/mule-http.xsd
http://www.mulesoft.org/schema/mule/json http://www.mulesoft.org/schema/mule/json/current/mule-json.xsd">
    <http:listener-config name="HTTP_Listener_Configuration" host="0.0.0.0" port="8110" doc:name="HTTP Listener Configuration"/>
    <http:request-config name="HTTP_Request_Configuration"  host="api.bonanza.com" port="443" doc:name="HTTP Request Configuration" protocol="HTTPS"/>
    <flow name="bonanza_fetchtoken_ceFlow">
        <http:listener config-ref="HTTP_Listener_Configuration" path="/fetchtoken" allowedMethods="GET" doc:name="HTTP"/>
        <message-properties-transformer doc:name="Message Properties">
            <add-message-property key="X-BONANZLE-API-DEV-NAME" value="t**********I"/>
            <add-message-property key="X-BONANZLE-API-CERT-NAME" value="l**********F"/>
        </message-properties-transformer>
        <set-payload value="fetchTokenRequest" doc:name="Set Payload"/>
        <set-property propertyName="Content-Type" value="text/plain" doc:name="Property"/>
        <set-property propertyName="Accept" value="application/json" doc:name="Property"/>
        <http:request config-ref="HTTP_Request_Configuration" path="/api_requests/secure_request" method="POST" doc:name="HTTP" followRedirects="true" parseResponse="false">
            <http:success-status-code-validator values="0..599"/>
        </http:request>
    </flow>
</mule>

In the API documentation, they have provided the sample code for java to send and receive response and it is working in my local too. The java code snippet is below.

import org.json.JSONObject;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.net.URL;
import java.net.HttpURLConnection;

public class FetchToken {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        try {
            String devId = "t******I";
            String certId = "l*******F";

            URL url = new URL("https://api.bonanza.com/api_requests/secure_request");
            HttpURLConnection connection = (HttpURLConnection) url.openConnection();

            connection.setRequestMethod("POST");
            connection.setDoOutput(true);
            connection.setRequestProperty("Accept", "application/json");
            connection.setRequestProperty("X-BONANZLE-API-DEV-NAME", devId);
            connection.setRequestProperty("X-BONANZLE-API-CERT-NAME", certId);

            OutputStreamWriter writer = new OutputStreamWriter(connection.getOutputStream());

            String requestName = "fetchTokenRequest";

            writer.write(requestName);
            writer.flush();
            writer.close();

            BufferedReader in = new BufferedReader(new InputStreamReader(connection.getInputStream()));
            String response = in.readLine();

            JSONObject jsonResponse = new JSONObject(response);

            if (jsonResponse.optString("ack").equals("Success") 
                    && jsonResponse.optJSONObject("fetchTokenResponse") != null) {
                // Success! Now read more keys from the json object
                JSONObject fetchTokenJson = jsonResponse.optJSONObject("fetchTokenResponse");

                System.out.println("Your token: " + fetchTokenJson.optString("authToken"));
                System.out.println("Token expiration time: " + fetchTokenJson.optString("hardExpirationTime"));
                System.out.println("Authentication URL: " + fetchTokenJson.optString("authenticationURL"));
            }


        } catch (Exception e) {
            System.out.println(e);
        }
    }
}

The above java program retuning token without issue. When i use my esb mule i am getting below API error. What are the mistakes i doing while building request. How can i get successful response from API ?

{
  "ack": "Failure",
  "version": "1.0beta",
  "timestamp": "2016-03-09T10:35:16.000Z",
  "errorMessage": {
    "message": "Cannot determine what type of request you are making. Often this can be the result of data that has not been escaped before being passed to the API. If you are passing data with quotation marks or other special characters, you should translate it to JSON, then escape it, before sending it over the API."
  }
}

Answer 1

Solving your problem implies performing debugging steps. I'm going to walk you through them.

Hypothesis: Maybe the receiving service is confused by some extra headers sent by Mule?

Try the following:

• Send the Mule request to http://requestb.in/ and look exactly how it is structured.
• Then send the same request to api.bonanza.com from Java, it should fail too.
• Remove extra stuff bit by bit until it works.
• Then come back to Mule and ensure that it creates the same request by tuning the headers it sends, fixing any other differences...