Ballerina Connector for WSO2 Micro Integrator

Overview

The Ballerina connector for WSO2 Micro Integrator allows you to run Ballerina transformations on WSO2 Micro Integrator. This integration enables you to leverage the powerful transformation capabilities of Ballerina within the environment of WSO2 Micro Integrator.

Steps to Create Ballerina Connector

Pull mi Tool

First, you need to pull the mi tool which is used to create the Ballerina connector.

bal tool pull mi

Write Ballerina Transformation

Next, you need to write the Ballerina transformation in a Ballerina project. Create a new Ballerina project or use an existing one and write your transformation logic. For example,

@mi:ConnectorInfo {}
public function GPA(xml rawMarks, xml credits) returns xml {
   // Your logic to calculate the GPA
}

Ballerina function that contains @mi:ConnectorInfo annotation maps with a component in Ballerina connector.

Generate the connector

Finally, use the bal mi command to generate the Ballerina connector for the WSO2 Micro Integrator.

bal mi -i <path_to_ballerina_project>

Above command generates the connector zip in the same location.

Local Build

1. Clone the repository module-ballerinax-wso2.mi

2. Build the compiler plugin and publish locally:

   ./gradlew clean :mi-ballerina:localPublish

3. Build the tool and publish locally:

   ./gradlew clean :tool-mi:localPublish 

Run tests

./gradlew test

Performance Test Description for WSO2 MI Connector

Overview

The performance test for the WSO2 MI connector was conducted using JMeter with 60 users. The aim was to evaluate the throughput per second for different payload sizes using three different transformation methods: Ballerina JSON transformation, Ballerina record transformation, and Java class mediator.

Results

The following table shows the throughput per second for each transformation method across different payload sizes:

Payload Size	Ballerina JSON transformation	Ballerina record transformation	Java class mediator
50B	13629.09	12587.48	15914.99
1024B	8151.94	8032.21	13035.26
10240B	1522.99	1548.53	12807.91
102400B	118.60	118.79	4792.20

Test Code

The specific code used for each transformation method is provided below:

Ballerina JSON Transformation:

function getPayloadLenFromJson(json j) returns decimal {
    json|error payload = j.payload;
    if payload is error {
        return -1;
    }
    string str = <string> payload;
    decimal len = 0;
    foreach var _ in str {
        len = decimal:sum(len, 1);
    }
    return len;
}

Ballerina Record Transformation:

type Payload record {|
    string size;
    string payload;
|};

function getPayloadLenFromRecord(json j) returns decimal {
    Payload|error payload = j.cloneWithType();
    if payload is error {
        return -1;
    }
    string str = payload.payload;
    decimal len = 0;
    foreach var _ in str {
        len = decimal:sum(len, 1);
    }
    return len;
}

Java Class Mediator:

import java.math.BigDecimal;

import org.apache.synapse.MessageContext;
import org.apache.synapse.commons.json.JsonUtil;
import org.apache.synapse.core.axis2.Axis2MessageContext;
import org.apache.synapse.mediators.AbstractMediator;

import com.google.gson.JsonElement;
import com.google.gson.JsonObject;
import com.google.gson.JsonParser;

public class PayloadLength extends AbstractMediator {

   private final JsonParser jsonParser = new JsonParser();

   public boolean mediate(MessageContext context) {
      String jsonString = JsonUtil.jsonPayloadToString(((Axis2MessageContext) context).getAxis2MessageContext());
      JsonElement jsonElement = jsonParser.parse(jsonString);
      JsonObject jsonObject = jsonElement.getAsJsonObject();
      String payload = jsonObject.get("payload").getAsString();

      BigDecimal len = new BigDecimal(0);
      for (int i=0; i < payload.length(); i++) {
         len = len.add(new BigDecimal(1));
      }

      context.setProperty("result", len.toString());
      return true;
   }
}

Contribute to Ballerina

As an open-source project, Ballerina welcomes contributions from the community.

For more information, go to the contribution guidelines.

Code of conduct

All the contributors are encouraged to read the Ballerina Code of Conduct.