org.camunda.connect.spi
Interface ConnectorRequestInterceptor

All Known Implementing Classes:

DebugRequestInterceptor

public interface ConnectorRequestInterceptor

A request interceptor. An interceptor allows intercepting the request created by a connector. See handleInvocation(ConnectorInvocation) for more details and usage patters.

The interceptor is invoked for every request created by a connector. As such, an interceptor implementation must be thread-safe.

Author:

Daniel Meyer

Method Summary

Object

handleInvocation(ConnectorInvocation invocation) Intercept and handle the actual invocation.

Method Detail

handleInvocation

Object handleInvocation(ConnectorInvocation invocation)
                        throws Exception

Intercept and handle the actual invocation. An implementation of this method *must* call invocation.proceed(); and return the result:

  public Object handleInvocation(ConnectorInvocation invocation) throws Exception {
    // do something before the request
    try {
      Object result = invocation.proceed();
      // do something after a successful request
      return result;
    } catch(Exception e) {
      // do something after a failed request
      throw e;
    }
  }
 

This may be useful for "management" use cases such as logging, failure tracking etc... and modifying the Thread context of the request thread (Security Context, Transactions, ...).

It is also possible for an implementation to access and modify the low level "raw" request object before it is executed by the connector:

  public Object handleInvocation(ConnectorInvocation invocation) throws Exception {
    Object rawRequest = invocation.getTarget();
    // cast rawRequest to the low-level connector implementation object and work with it.

    // finally
    return invocation.proceed();
  }
 

Parameters:

invocation - the invocation

Returns:

the result of the invocation

Throws:

Exception