com.centurylink.mdw.monitor

Interface AdapterMonitor

All Superinterfaces:

Monitor, RegisteredService

All Known Implementing Classes:

AdapterStubbingMonitor, TraceAdapterMonitor

public interface AdapterMonitor
extends RegisteredService, Monitor

AdapterMonitors can be registered through @Monitor annotations to intercept external service calls originating from MDW workflow adapter activities. Must be threadsafe. Normally all registered monitors are called in sequence. However the first monitor whose onInvoke() returns non-null breaks the chain, and this non-null response is passed back to the MDW runtime. Same instance is guaranteed for all lifecycle methods.

Method Summary

Modifier and Type	Method and Description
default java.lang.String	onError(ActivityRuntimeContext context, java.lang.Throwable t) Called when an error is encountered.
default java.lang.Object	onInvoke(ActivityRuntimeContext context, java.lang.Object request, java.util.Map<java.lang.String,java.lang.String> headers, java.lang.Object connection) Called after onRequest(), but before the service is actually invoked.
default java.lang.Object	onRequest(ActivityRuntimeContext context, java.lang.Object request, java.util.Map<java.lang.String,java.lang.String> headers, java.lang.Object connection) Called when the request is created.
default java.lang.Object	onResponse(ActivityRuntimeContext context, java.lang.Object response, java.util.Map<java.lang.String,java.lang.String> headers, java.lang.Object connection) Called when the response is received.

Methods inherited from interface com.centurylink.mdw.monitor.Monitor

isEnabled, isOffline

Method Detail

onRequest

default java.lang.Object onRequest(ActivityRuntimeContext context,
                                   java.lang.Object request,
                                   java.util.Map<java.lang.String,java.lang.String> headers,
                                   java.lang.Object connection)

Called when the request is created. Can change the request contents. Currently must return null or a String.

Parameters:

context - The workflow runtime context of the adapter activity

request - The request message content (String, XMLBean, JAXB Element, JSONObject, etc).

headers - Protocol header values. May be modified by the monitor.

Returns:

null, or an alternative request that should be sent to the called service

onInvoke

default java.lang.Object onInvoke(ActivityRuntimeContext context,
                                  java.lang.Object request,
                                  java.util.Map<java.lang.String,java.lang.String> headers,
                                  java.lang.Object connection)

Called after onRequest(), but before the service is actually invoked. Can be used to short-circuit (stub) the service. Currently must return null or a String. Returning non-null from here bypasses onResponse() and other chained monitors' onInvoke().

Parameters:

context - The workflow runtime context of the adapter activity

request - Outgoing request message content (String, XMLBean, JAXB Element, JSONObject, etc).

headers - protocol headers

Returns:

null, or an alternative response to send back to the MDW runtime

onResponse

default java.lang.Object onResponse(ActivityRuntimeContext context,
                                    java.lang.Object response,
                                    java.util.Map<java.lang.String,java.lang.String> headers,
                                    java.lang.Object connection)

Called when the response is received.

Parameters:

context - The workflow runtime context of the adapter activity

response - The response that was received from the external system. (String, XMLBean, JAXB Element, JSONObject, etc).

headers - Protocol headers for the incoming response. New headers can be injected by the monitor.

connection - Connection used in adapter

Returns:

Null unless the monitor wants to change the response contents. In that case, return the alternative response.

onError

default java.lang.String onError(ActivityRuntimeContext context,
                                 java.lang.Throwable t)

Called when an error is encountered.

Parameters:

context - adapter workflow context

t - error that was encountered

Returns:

null, or activity result code