core-connectors-camel-common

This project has below implementations,

1. Handles all the global errors/exceptions that gets raised in pm4l-core-connector.
2. Implements HealthRouter for GET /health endpoint.

How to Use

1. Build the project to generate the jar.

   mvn clean package
   

2. Use this jar as dependency in pm4ml-core-connector.

   <dependency>
       <groupId>com.modus.pm4ml.core.connectors.common</groupId>
       <artifactId>core-connectors-camel-common</artifactId>
       <version>1.0.0-SNAPSHOT</version>
   </dependency>
   

3. In the core connector, implement the route for "direct:extractCustomErrors".

   Below is the sample implementation of this route, in core connector.

   Declare the route for, "direct:extractCustomErrors"

   import com.modusbox.client.processor.CustomErrorProcessor;
   import org.apache.camel.builder.RouteBuilder;
   
   public final class CustomErrorRouter extends RouteBuilder {
       private CustomErrorProcessor customErrorProcessor = new CustomErrorProcessor();
   
       public void configure() {
   
           from("direct:extractCustomErrors")
               .process(customErrorProcessor)
           ;
       }
   }
   

   Add this router to the Camel Context

   <bean id="customErrorRouter" class="com.modusbox.client.router.CustomErrorRouter" />
   
   <camel:camelContext>
       ....
       ....
       <camel:routeBuilder ref="customErrorRouter"/>
   </camel:camelContext>
   
   or you can load whole package into the camel context like below,
   
   <camel:camelContext>
      <camel:package>com.modusbox.client.router</camel:package>
   </camel:camelContext>
   

   Implement the CustomErrorProcessor to handle Core Connector specific errors.

   import com.modusbox.log4j2.message.CustomJsonMessage;
   import com.modusbox.log4j2.message.CustomJsonMessageImpl;
   import org.apache.camel.Exchange;
   import org.apache.camel.Processor;
   import org.apache.camel.http.base.HttpOperationFailedException;
   import org.json.JSONObject;
   import org.springframework.stereotype.Component;
   
   @Component("customErrorProcessor")
   public class CustomErrorProcessor implements Processor {
   
       CustomJsonMessage customJsonMessage = new CustomJsonMessageImpl();
   
       @Override
       public void process(Exchange exchange) throws Exception {
   
           String reasonText = "{ \"statusCode\": \"5000\"," +
                                   "\"message\": \"Unknown\" }";
           String statusCode = "5000";
           int httpResponseCode = 500;
   
           // The exception may be in 1 of 2 places
           Exception exception = exchange.getException();
           if (exception == null) {
               exception = exchange.getProperty(Exchange.EXCEPTION_CAUGHT, Exception.class);
           }
   
           if (exception != null) {
               if (exception instanceof HttpOperationFailedException) {
                   HttpOperationFailedException e = (HttpOperationFailedException) exception;
                   String errorDescription = "Downstream API failed.";
                   try {
                       if (null != e.getResponseBody()) {
                           /* Below if block needs to be changed as per the error object structure specific to 
                               CBS back end API that is being integrated in Core Connector. */
                           JSONObject respObject = new JSONObject(e.getResponseBody());
                           if (respObject.has("returnStatus")) {
                               statusCode = String.valueOf(respObject.getInt("returnCode"));
                               errorDescription = respObject.getString("returnStatus");
                           }
                       }
                   } finally {
                       reasonText = "{ \"statusCode\": \"" + statusCode + "\"," +
                                       "\"message\": \"" + errorDescription + "\"} ";
                   }
               }
               customJsonMessage.logJsonMessage("error", String.valueOf(exchange.getIn().getHeader("X-CorrelationId")),
                                                   "Processing the exception at CustomErrorProcessor", null, null,
                                                       exception.getMessage());
           }
   
           exchange.getMessage().setHeader(Exchange.HTTP_RESPONSE_CODE, httpResponseCode);
           exchange.getMessage().setHeader(Exchange.CONTENT_TYPE, "application/json");
           exchange.getMessage().setBody(reasonText);
       }
   }
   

4. In the core connector, add HealthRouter to the Camel Context

   <bean id="healthRouter" class="com.modusbox.client.router.HealthRouter" />
   
   <camel:camelContext>
       ....
       ....
       <camel:routeBuilder ref="healthRouter"/>
   </camel:camelContext>
   
   or you can load whole package into the camel context like below,
   
   <camel:camelContext>
       <camel:package>com.modusbox.client.router</camel:package>
   </camel:camelContext>
   

   And add below as servicebean to cxf server,

   <bean class="com.modusbox.client.jaxrs.HealthApiImpl"/>
   
   Eg:
   
   <camelcxf:rsServer ....>
       <camelcxf:serviceBeans>
           ....
           ....
           <bean class="com.modusbox.client.jaxrs.HealthApiImpl"/>
       </camelcxf:serviceBeans>
       ....
       ....
   </camelcxf:rsServer>