RestWorkflowInterceptor.java
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* Licensed to the Apache Software Foundation (ASF) under one
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* distributed with this work for additional information
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* to you 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
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* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
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*/
package org.apache.struts2.rest;
import org.apache.struts2.action.Action;
import org.apache.struts2.ActionContext;
import org.apache.struts2.ActionInvocation;
import org.apache.struts2.inject.Inject;
import org.apache.struts2.interceptor.MethodFilterInterceptor;
import org.apache.struts2.interceptor.ValidationAware;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.apache.struts2.dispatcher.mapper.ActionMapping;
import java.util.HashMap;
import java.util.Map;
import static jakarta.servlet.http.HttpServletResponse.SC_BAD_REQUEST;
/**
* An interceptor that makes sure there are not validation errors before allowing the interceptor chain to continue.
* <b>This interceptor does not perform any validation</b>.
*
* <p>
* Copied from the {@link org.apache.struts2.interceptor.DefaultWorkflowInterceptor}, this interceptor adds support
* for error handling of Restful operations. For example, if an validation error is discovered, a map of errors
* is created and processed to be returned, using the appropriate content handler for rendering the body.
* </p>
*
* <p>
* This interceptor does nothing if the name of the method being invoked is specified in the <b>excludeMethods</b>
* parameter. <b>excludeMethods</b> accepts a comma-delimited list of method names. For example, requests to
* <b>foo!input.action</b> and <b>foo!back.action</b> will be skipped by this interceptor if you set the
* <b>excludeMethods</b> parameter to "input, back".
* </p>
*
* <p>
* <b>Note:</b> As this method extends off MethodFilterInterceptor, it is capable of
* deciding if it is applicable only to selective methods in the action class. This is done by adding param tags
* for the interceptor element, naming either a list of excluded method names and/or a list of included method
* names, whereby includeMethods overrides excludedMethods. A single * sign is interpreted as wildcard matching
* all methods for both parameters.
* See {@link MethodFilterInterceptor} for more info.
* </p>
*
* <b>Interceptor parameters:</b>
*
* <ul>
* <li>inputResultName - Default to "input". Determine the result name to be returned when
* an action / field error is found.</li>
* </ul>
*
* <b>Extending the interceptor:</b>
* There are no known extension points for this interceptor.
*
* <b>Example code:</b>
*
* <pre>
* <action name="someAction" class="com.examples.SomeAction">
* <interceptor-ref name="params"/>
* <interceptor-ref name="validation"/>
* <interceptor-ref name="workflow"/>
* <result name="success">good_result.ftl</result>
* </action>
*
* <-- In this case myMethod as well as mySecondMethod of the action class
* will not pass through the workflow process -->
* <action name="someAction" class="com.examples.SomeAction">
* <interceptor-ref name="params"/>
* <interceptor-ref name="validation"/>
* <interceptor-ref name="workflow">
* <param name="excludeMethods">myMethod,mySecondMethod</param>
* </interceptor-ref name="workflow">
* <result name="success">good_result.ftl</result>
* </action>
*
* <-- In this case, the result named "error" will be used when
* an action / field error is found -->
* <-- The Interceptor will only be applied for myWorkflowMethod method of action
* classes, since this is the only included method while any others are excluded -->
* <action name="someAction" class="com.examples.SomeAction">
* <interceptor-ref name="params"/>
* <interceptor-ref name="validation"/>
* <interceptor-ref name="workflow">
* <param name="inputResultName">error</param>
* <param name="excludeMethods">*</param>
* <param name="includeMethods">myWorkflowMethod</param>
* </interceptor-ref>
* <result name="success">good_result.ftl</result>
* </action>
* </pre>
*
* @author Jason Carreira
* @author Rainer Hermanns
* @author <a href='mailto:the_mindstorm[at]evolva[dot]ro'>Alexandru Popescu</a>
* @author Philip Luppens
* @author tm_jee
*/
public class RestWorkflowInterceptor extends MethodFilterInterceptor {
private static final long serialVersionUID = 7563014655616490865L;
private static final Logger LOG = LogManager.getLogger(RestWorkflowInterceptor.class);
private String inputResultName = Action.INPUT;
private ContentTypeHandlerManager manager;
private String postMethodName = "create";
private String editMethodName = "edit";
private String newMethodName = "editNew";
private String putMethodName = "update";
private int validationFailureStatusCode = SC_BAD_REQUEST;
@Inject(required = false, value = RestConstants.REST_MAPPER_POST_METHOD_NAME)
public void setPostMethodName(String postMethodName) {
this.postMethodName = postMethodName;
}
@Inject(required = false, value = RestConstants.REST_MAPPER_EDIT_METHOD_NAME)
public void setEditMethodName(String editMethodName) {
this.editMethodName = editMethodName;
}
@Inject(required = false, value = RestConstants.REST_MAPPER_NEW_METHOD_NAME)
public void setNewMethodName(String newMethodName) {
this.newMethodName = newMethodName;
}
@Inject(required = false, value = RestConstants.REST_MAPPER_PUT_METHOD_NAME)
public void setPutMethodName(String putMethodName) {
this.putMethodName = putMethodName;
}
@Inject(required = false, value = RestConstants.REST_VALIDATION_FAILURE_STATUS_CODE)
public void setValidationFailureStatusCode(String code) {
this.validationFailureStatusCode = Integer.parseInt(code);
}
@Inject
public void setContentTypeHandlerManager(ContentTypeHandlerManager mgr) {
this.manager = mgr;
}
/**
* Set the <code>inputResultName</code> (result name to be returned when
* a action / field error is found registered). Default to {@link Action#INPUT}
*
* @param inputResultName what result name to use when there was validation error(s).
*/
public void setInputResultName(String inputResultName) {
this.inputResultName = inputResultName;
}
/**
* Intercept {@link ActionInvocation} and processes the errors using the {@link org.apache.struts2.rest.handler.ContentTypeHandler}
* appropriate for the request.
*
* @return String result name
*/
protected String doIntercept(ActionInvocation invocation) throws Exception {
Object action = invocation.getAction();
if (action instanceof ValidationAware) {
ValidationAware validationAwareAction = (ValidationAware) action;
if (validationAwareAction.hasErrors()) {
LOG.debug("Errors on action {}, returning result name 'input'", validationAwareAction);
ActionMapping mapping = ActionContext.getContext().getActionMapping();
String method = inputResultName;
if (postMethodName.equals(mapping.getMethod())) {
method = newMethodName;
} else if (putMethodName.equals(mapping.getMethod())) {
method = editMethodName;
}
HttpHeaders info = new DefaultHttpHeaders()
.disableCaching()
.renderResult(method)
.withStatus(validationFailureStatusCode);
Map<String, Object> errors = new HashMap<>();
errors.put("actionErrors", validationAwareAction.getActionErrors());
errors.put("fieldErrors", validationAwareAction.getFieldErrors());
return manager.handleResult(invocation, info, errors);
}
}
return invocation.invoke();
}
}