/*
 * Copyright 2008 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.ws.client.support.interceptor;

import org.springframework.ws.client.WebServiceClientException;
import org.springframework.ws.context.MessageContext;
import org.springframework.ws.soap.SoapHeader;
import org.springframework.ws.transport.WebServiceConnection;

/**
 * Workflow interface that allows for customized client-side message interception. Applications can register any number
 * of existing or custom interceptors on a {@link org.springframework.ws.client.core.WebServiceTemplate}, to add common
 * pre- and postprocessing behavior without needing to modify payload handling code.
 *
 * <p>A {@code ClientInterceptor} gets called after payload creation (using {@link
 * org.springframework.ws.client.core.WebServiceTemplate#marshalSendAndReceive(Object)} or similar methods, and after
 * {@link org.springframework.ws.client.core.WebServiceMessageCallback callback} invocation, but before the message is
 * sent over the {@link WebServiceConnection}. This mechanism can be used for a large field of preprocessing aspects,
 * e.g. for authorization checks, or message header checks. Its main purpose is to allow for factoring out meta-data
 * (i.e. {@link SoapHeader}) related code.
 *
 * <p>Client interceptors are defined on a {@link org.springframework.ws.client.core.WebServiceTemplate}, using the {@link
 * org.springframework.ws.client.core.WebServiceTemplate#setInterceptors(ClientInterceptor[]) interceptors} property.
 *
 * @author Giovanni Cuccu
 * @author Arjen Poutsma
 * @see org.springframework.ws.client.core.WebServiceTemplate#setInterceptors(ClientInterceptor[])
 * @since 1.5.0
 */
public interface ClientInterceptor {

	/**
	 * Processes the outgoing request message. Called after payload creation and callback invocation, but before the
	 * message is sent.
	 *
	 * @param messageContext contains the outgoing request message
	 * @return {@code true} to continue processing of the request interceptors; {@code false} to indicate
	 *		   blocking of the request endpoint chain
	 * @throws WebServiceClientException in case of errors
	 * @see MessageContext#getRequest()
	 */
	boolean handleRequest(MessageContext messageContext) throws WebServiceClientException;

	/**
	 * Processes the incoming response message. Called for non-fault response messages before payload handling in the
	 * {@link org.springframework.ws.client.core.WebServiceTemplate}.
	 *
	 * <p>Note: Will only be called if this interceptor's {@link #handleRequest}  method has successfully completed.
	 *
	 * @param messageContext contains the outgoing request message
	 * @return {@code true} to continue processing of the request interceptors; {@code false} to indicate
	 *		   blocking of the response endpoint chain
	 * @throws WebServiceClientException in case of errors
	 * @see MessageContext#getResponse()
	 */
	boolean handleResponse(MessageContext messageContext) throws WebServiceClientException;

	/**
	 * Processes the incoming response fault. Called for response fault messages before payload handling in the {@link
	 * org.springframework.ws.client.core.WebServiceTemplate}.
	 *
	 * <p>Note: Will only be called if this interceptor's {@link #handleRequest}  method has successfully completed.
	 *
	 * @param messageContext contains the outgoing request message
	 * @return {@code true} to continue processing of the request interceptors; {@code false} to indicate
	 *		   blocking of the request endpoint chain
	 * @throws WebServiceClientException in case of errors
	 * @see MessageContext#getResponse()
	 * @see org.springframework.ws.FaultAwareWebServiceMessage#hasFault()
	 */
	boolean handleFault(MessageContext messageContext) throws WebServiceClientException;

	/**
	 * Callback after completion of request and response (fault) processing. Will be called on any outcome, thus
	 * allows for proper resource cleanup.
	 *
	 * <p>Note: Will only be called if this interceptor's {@link #handleRequest}  method has successfully completed.
	 *
	 * @param messageContext contains both request and response messages, the response should contains a Fault
	 * @param ex exception thrown on handler execution, if any
	 * @throws WebServiceClientException in case of errors
	 * @since 2.2
	 */
	void afterCompletion(MessageContext messageContext, Exception ex) throws WebServiceClientException;


}