Merge pull request #2266 from GDLMadushanka/triggerError

Add Trigger Error mediator

modules/core/src/main/java/org/apache/synapse/SynapseConstants.java

@@ -628,4 +628,6 @@ public enum ENDPOINT_TIMEOUT_TYPE { ENDPOINT_TIMEOUT, GLOBAL_TIMEOUT, HTTP_CONNE
 
     public static final String SCATTER_MESSAGES = "SCATTER_MESSAGES";
     public static final String CONTINUE_FLOW_TRIGGERED_FROM_MEDIATOR_WORKER = "CONTINUE_FLOW_TRIGGERED_FROM_MEDIATOR_WORKER";
+
+    public static final String DEFAULT_ERROR_TYPE = "ANY";
 }

modules/core/src/main/java/org/apache/synapse/config/xml/MediatorFactoryFinder.java

@@ -104,7 +104,8 @@ public class MediatorFactoryFinder implements XMLToObjectMapper {
             JSONTransformMediatorFactory.class,
             NTLMMediatorFactory.class,
             VariableMediatorFactory.class,
-            ScatterGatherMediatorFactory.class
+            ScatterGatherMediatorFactory.class,
+            ThrowErrorMediatorFactory.class
     };
 
     private final static MediatorFactoryFinder instance  = new MediatorFactoryFinder();

modules/core/src/main/java/org/apache/synapse/config/xml/MediatorSerializerFinder.java

@@ -78,7 +78,8 @@ public class MediatorSerializerFinder {
             JSONTransformMediatorSerializer.class,
             NTLMMediatorSerializer.class,
             VariableMediatorSerializer.class,
-            ScatterGatherMediatorSerializer.class
+            ScatterGatherMediatorSerializer.class,
+            ThrowErrorMediatorSerializer.class
     };
 
     private final static MediatorSerializerFinder instance = new MediatorSerializerFinder();

modules/core/src/main/java/org/apache/synapse/config/xml/SynapsePathSerializer.java

@@ -71,6 +71,14 @@ public static OMElement serializePath(SynapsePath path, String expression,
             } else if(path.getPathType() == SynapsePath.X_PATH) {
                 elem.addAttribute(elem.getOMFactory().createOMAttribute(
                         attribName, nullNS, expression));
+            } else if (path.getPathType() == SynapsePath.SYNAPSE_EXPRESSIONS_PATH) {
+                if (expression.startsWith("{") && expression.endsWith("}")) {
+                    elem.addAttribute(elem.getOMFactory().createOMAttribute(
+                            attribName, nullNS, expression));
+                } else {
+                    elem.addAttribute(elem.getOMFactory().createOMAttribute(
+                            attribName, nullNS, "{" + expression + "}"));
+                }
             }
 
             serializeNamespaces(elem, path);

modules/core/src/main/java/org/apache/synapse/config/xml/ThrowErrorMediatorFactory.java

@@ -0,0 +1,71 @@
+/*
+ *  Copyright (c) 2024, WSO2 LLC. (http://www.wso2.org) All Rights Reserved.
+ *
+ *  WSO2 LLC. licenses this file 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
+ *  "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.apache.synapse.config.xml;
+
+import org.apache.axiom.om.OMAttribute;
+import org.apache.axiom.om.OMElement;
+import org.apache.synapse.Mediator;
+import org.apache.synapse.SynapseConstants;
+import org.apache.synapse.mediators.Value;
+import org.apache.synapse.mediators.v2.ThrowError;
+
+import javax.xml.namespace.QName;
+import java.util.Properties;
+
+/**
+ * Creates a throw error mediator through the supplied XML configuration
+ * <p/>
+ * <pre>
+ * &lt;throwError (type="string") (errorMessage=("string" | expression))/&gt;
+ * </pre>
+ */
+public class ThrowErrorMediatorFactory extends AbstractMediatorFactory {
+
+    private static final String ERROR_MESSAGE = "errorMessage";
+    private static final String THROW_ERROR = "throwError";
+    private static final QName ATT_ERROR_MSG = new QName(ERROR_MESSAGE);
+    private static final QName ATT_TYPE = new QName("type");
+    private static final QName THROW_ERROR_Q
+            = new QName(XMLConfigConstants.SYNAPSE_NAMESPACE, THROW_ERROR);
+
+    @Override
+    protected Mediator createSpecificMediator(OMElement elem, Properties properties) {
+        ThrowError throwErrorMediator = new ThrowError();
+        OMAttribute type = elem.getAttribute(ATT_TYPE);
+        OMAttribute errorMsg = elem.getAttribute(ATT_ERROR_MSG);
+
+        if (type == null || type.getAttributeValue().isEmpty()) {
+            throwErrorMediator.setType(SynapseConstants.DEFAULT_ERROR_TYPE);
+        } else {
+            throwErrorMediator.setType(type.getAttributeValue());
+        }
+        if (errorMsg == null || errorMsg.getAttributeValue().isEmpty()) {
+            throwErrorMediator.setErrorMsg(new Value("Error occurred in the mediation flow"));
+        } else {
+            ValueFactory msgFactory = new ValueFactory();
+            Value generatedMsg = msgFactory.createValue(ERROR_MESSAGE, elem);
+            throwErrorMediator.setErrorMsg(generatedMsg);
+        }
+        return throwErrorMediator;
+    }
+
+    @Override
+    public QName getTagQName() {
+        return THROW_ERROR_Q;
+    }
+}

modules/core/src/main/java/org/apache/synapse/config/xml/ThrowErrorMediatorSerializer.java

@@ -0,0 +1,57 @@
+/*
+ *  Copyright (c) 2024, WSO2 LLC. (http://www.wso2.org) All Rights Reserved.
+ *
+ *  WSO2 LLC. licenses this file 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
+ *  "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.apache.synapse.config.xml;
+
+import org.apache.axiom.om.OMElement;
+import org.apache.synapse.Mediator;
+import org.apache.synapse.mediators.v2.ThrowError;
+
+/**
+ * <pre>
+ * &lt;throwError (type="string") (errorMessage=("string" | expression))/&gt;
+ * </pre>
+ */
+public class ThrowErrorMediatorSerializer extends AbstractMediatorSerializer{
+
+    @Override
+    protected OMElement serializeSpecificMediator(Mediator m) {
+        if (!(m instanceof ThrowError)) {
+            handleException("Unsupported mediator passed in for serialization : " + m.getType());
+        }
+
+        ThrowError mediator = (ThrowError) m;
+        OMElement throwError = fac.createOMElement("throwError", synNS);
+        saveTracingState(throwError, mediator);
+
+        if (mediator.getType() != null) {
+            throwError.addAttribute(fac.createOMAttribute("type", nullNS, mediator.getType()));
+        }
+        if (mediator.getErrorMsg() != null) {
+            ValueSerializer valueSerializer = new ValueSerializer();
+            valueSerializer.serializeValue(mediator.getErrorMsg(), "errorMessage", throwError);
+        }
+
+        serializeComments(throwError, mediator.getCommentsList());
+        return throwError;
+    }
+
+    @Override
+    public String getMediatorClassName() {
+        return ThrowError.class.getName();
+    }
+}

modules/core/src/main/java/org/apache/synapse/mediators/v2/ThrowError.java

@@ -0,0 +1,74 @@
+/*
+ *  Copyright (c) 2024, WSO2 LLC. (http://www.wso2.org) All Rights Reserved.
+ *
+ *  WSO2 LLC. licenses this file 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
+ *  "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.apache.synapse.mediators.v2;
+
+import org.apache.synapse.MessageContext;
+import org.apache.synapse.SynapseConstants;
+import org.apache.synapse.SynapseException;
+import org.apache.synapse.SynapseLog;
+import org.apache.synapse.mediators.AbstractMediator;
+import org.apache.synapse.mediators.Value;
+
+/**
+ * This mediator is used to throw an error from the mediation flow.
+ */
+public class ThrowError extends AbstractMediator {
+    private String type = null;
+    private Value errorMsg = null;
+
+    @Override
+    public boolean mediate(MessageContext synCtx) {
+        if (synCtx.getEnvironment().isDebuggerEnabled()) {
+            if (super.divertMediationRoute(synCtx)) {
+                return true;
+            }
+        }
+
+        SynapseLog synLog = getLog(synCtx);
+        if (synLog.isTraceOrDebugEnabled()) {
+            synLog.traceOrDebug("Start : ThrowError mediator");
+            if (synLog.isTraceTraceEnabled()) {
+                synLog.traceTrace("Message : " + synCtx.getEnvelope());
+            }
+        }
+
+        String error = errorMsg.evaluateValue(synCtx);
+
+        synLog.traceOrDebug("End : ThrowError mediator");
+        synCtx.setProperty(SynapseConstants.ERROR_CODE, type);
+        synCtx.setProperty(SynapseConstants.ERROR_MESSAGE, error);
+        throw new SynapseException(error, new Throwable(type));
+    }
+
+    @Override
+    public String getType() {
+        return type;
+    }
+
+    public void setType(String type) {
+        this.type = type;
+    }
+
+    public Value getErrorMsg() {
+        return errorMsg;
+    }
+
+    public void setErrorMsg(Value errorMsg) {
+        this.errorMsg = errorMsg;
+    }
+}

modules/core/src/test/java/org/apache/synapse/config/xml/ThrowErrorMediatorFactoryTest.java

@@ -0,0 +1,55 @@
+/*
+ *  Copyright (c) 2024, WSO2 LLC. (http://www.wso2.org) All Rights Reserved.
+ *
+ *  WSO2 LLC. licenses this file 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
+ *  "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.apache.synapse.config.xml;
+
+import org.apache.axiom.om.OMElement;
+import org.apache.axiom.om.util.AXIOMUtil;
+import org.apache.synapse.mediators.v2.ThrowError;
+import org.junit.Assert;
+import org.junit.Test;
+
+import javax.xml.stream.XMLStreamException;
+
+/**
+ * This is the test class for ThrowErrorMediatorFactory class.
+ */
+public class ThrowErrorMediatorFactoryTest {
+
+    /**
+     * Test create TriggerError with given XML configuration and asserting it is created.
+     *
+     * @throws XMLStreamException - XMLStreamException
+     */
+    @Test
+    public void testThrowErrorExp() throws XMLStreamException {
+        String inputXML = "<throwError type=\"HTTP:TIMEOUT\" errorMessage=\"{${$.abc}}\"/>";
+        OMElement element = AXIOMUtil.stringToOM(inputXML);
+        ThrowErrorMediatorFactory throwErrorMediatorFactory = new ThrowErrorMediatorFactory();
+        ThrowError throwError = (ThrowError) throwErrorMediatorFactory.createSpecificMediator(element,null);
+        Assert.assertEquals("$.abc", throwError.getErrorMsg().getExpression().toString());
+    }
+
+    @Test
+    public void testThrowErrorMsg() throws XMLStreamException {
+        String inputXML = "<throwError type=\"HTTP:TIMEOUT\" errorMessage=\"string error message\"/>";
+        OMElement element = AXIOMUtil.stringToOM(inputXML);
+        ThrowErrorMediatorFactory throwErrorMediatorFactory = new ThrowErrorMediatorFactory();
+        ThrowError throwError = (ThrowError) throwErrorMediatorFactory.createSpecificMediator(element,null);
+        Assert.assertEquals("string error message", throwError.getErrorMsg().getKeyValue());
+    }
+}

modules/core/src/test/java/org/apache/synapse/config/xml/ThrowErrorMediatorSerializerTest.java

@@ -0,0 +1,31 @@
+package org.apache.synapse.config.xml;
+
+import org.apache.axiom.om.OMElement;
+import org.apache.synapse.mediators.Value;
+import org.apache.synapse.mediators.v2.ThrowError;
+import org.apache.synapse.util.xpath.SynapseExpression;
+import org.jaxen.JaxenException;
+import org.junit.Assert;
+import org.junit.Test;
+
+import javax.xml.namespace.QName;
+
+public class ThrowErrorMediatorSerializerTest {
+
+    @Test
+    public void testSerializeThrowErrorMediator() throws JaxenException {
+        ThrowErrorMediatorSerializer throwErrorMediatorSerializer = new ThrowErrorMediatorSerializer();
+        ThrowError mediator = new ThrowError();
+        String type = "TRANSPORT:TIMEOUT";
+        String err = "Error occurred";
+        String exp = "${payload.err}";
+        mediator.setErrorMsg(new Value(err));
+        mediator.setType(type);
+        OMElement element = throwErrorMediatorSerializer.serializeSpecificMediator(mediator);
+        Assert.assertEquals("invalid type", type, element.getAttributeValue(new QName("type")));
+        Assert.assertEquals("invalid error message", err, element.getAttributeValue(new QName("errorMessage")));
+        mediator.setErrorMsg(new Value(new SynapseExpression(exp)));
+        element = throwErrorMediatorSerializer.serializeSpecificMediator(mediator);
+        Assert.assertEquals("invalid error message", "{" + exp + "}", element.getAttributeValue(new QName("errorMessage")));
+    }
+}