Map http 404 to Java Optional.empty [#1520]

streampipes-client/pom.xml

@@ -97,8 +97,13 @@
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-checkstyle-plugin</artifactId>
+                <configuration>
+                    <propertyExpansion>
+                		checkstyle.config.base.path=${project.parent.basedir}/tools/maven
+                	</propertyExpansion>
+                </configuration>
             </plugin>
         </plugins>
     </build>
 
-</project>
+</project>

streampipes-client/src/main/java/org/apache/streampipes/client/api/AbstractTypedClientApi.java

@@ -22,9 +22,11 @@
 import org.apache.streampipes.client.serializer.ListSerializer;
 import org.apache.streampipes.client.serializer.ObjectSerializer;
 import org.apache.streampipes.client.util.StreamPipesApiPath;
+import org.apache.streampipes.commons.exceptions.SpHttpErrorStatusCode;
 import org.apache.streampipes.commons.exceptions.SpRuntimeException;
 
 import java.util.List;
+import java.util.Optional;
 
 public abstract class AbstractTypedClientApi<T> extends AbstractClientApi {
 
@@ -40,9 +42,17 @@ protected List<T> getAll(StreamPipesApiPath apiPath) throws SpRuntimeException {
     return new GetRequest<>(clientConfig, apiPath, targetClass, serializer).executeRequest();
   }
 
-  protected T getSingle(StreamPipesApiPath apiPath) throws SpRuntimeException {
+  protected Optional<T> getSingle(StreamPipesApiPath apiPath) throws SpRuntimeException {
     ObjectSerializer<Void, T> serializer = new ObjectSerializer<>();
-    return new GetRequest<>(clientConfig, apiPath, targetClass, serializer).executeRequest();
+    try {
+      return Optional.of(new GetRequest<>(clientConfig, apiPath, targetClass, serializer).executeRequest());
+    } catch (SpHttpErrorStatusCode e) {
+      if (e.getHttpStatusCode() == 404) {
+        return Optional.empty();
+      } else {
+        throw e;
+      }
+    }
   }
 
   protected abstract StreamPipesApiPath getBaseResourcePath();

streampipes-client/src/main/java/org/apache/streampipes/client/api/CRUDApi.java

@@ -18,10 +18,11 @@
 package org.apache.streampipes.client.api;
 
 import java.util.List;
+import java.util.Optional;
 
 public interface CRUDApi<K, V> {
 
-  V get(K id);
+  Optional<V> get(K id);
 
   List<V> all();
 

streampipes-client/src/main/java/org/apache/streampipes/client/api/DataLakeMeasureApi.java

@@ -23,6 +23,7 @@
 import org.apache.streampipes.model.datalake.DataLakeMeasure;
 
 import java.util.List;
+import java.util.Optional;
 
 public class DataLakeMeasureApi extends AbstractTypedClientApi<DataLakeMeasure>
     implements CRUDApi<String, DataLakeMeasure> {
@@ -31,7 +32,7 @@ public DataLakeMeasureApi(StreamPipesClientConfig clientConfig) {
     super(clientConfig, DataLakeMeasure.class);
   }
 
-  public DataLakeMeasure get(String id) {
+  public Optional<DataLakeMeasure> get(String id) {
     return getSingle(getBaseResourcePath().addToPath(id));
   }
 

streampipes-client/src/main/java/org/apache/streampipes/client/api/DataProcessorApi.java

@@ -28,6 +28,7 @@
 import org.apache.streampipes.model.graph.DataProcessorInvocation;
 
 import java.util.List;
+import java.util.Optional;
 
 public class DataProcessorApi extends AbstractTypedClientApi<DataProcessorInvocation>
     implements CRUDApi<String, DataProcessorInvocation> {
@@ -43,7 +44,7 @@ protected StreamPipesApiPath getBaseResourcePath() {
   }
 
   @Override
-  public DataProcessorInvocation get(String s) {
+  public Optional<DataProcessorInvocation> get(String s) {
     return getSingle(getBaseResourcePath().addToPath(s));
   }
 

streampipes-client/src/main/java/org/apache/streampipes/client/api/DataSinkApi.java

@@ -27,6 +27,7 @@
 import org.apache.streampipes.model.graph.DataSinkInvocation;
 
 import java.util.List;
+import java.util.Optional;
 
 public class DataSinkApi extends AbstractTypedClientApi<DataSinkInvocation>
     implements CRUDApi<String, DataSinkInvocation> {
@@ -36,7 +37,7 @@ public DataSinkApi(StreamPipesClientConfig clientConfig) {
   }
 
   @Override
-  public DataSinkInvocation get(String s) {
+  public Optional<DataSinkInvocation> get(String s) {
     return getSingle(getBaseResourcePath().addToPath(s));
   }
 

streampipes-client/src/main/java/org/apache/streampipes/client/api/DataStreamApi.java

@@ -28,6 +28,7 @@
 
 import java.net.URLEncoder;
 import java.util.List;
+import java.util.Optional;
 
 public class DataStreamApi extends AbstractTypedClientApi<SpDataStream> implements CRUDApi<String, SpDataStream> {
 
@@ -36,7 +37,7 @@ public DataStreamApi(StreamPipesClientConfig clientConfig) {
   }
 
   @Override
-  public SpDataStream get(String streamId) {
+  public Optional<SpDataStream> get(String streamId) {
     return getSingle(StreamPipesApiPath.fromBaseApiPath()
         .addToPath("streams").addToPath(streamId));
   }

streampipes-client/src/main/java/org/apache/streampipes/client/api/PipelineApi.java

@@ -26,6 +26,7 @@
 import org.apache.streampipes.model.pipeline.PipelineOperationStatus;
 
 import java.util.List;
+import java.util.Optional;
 
 public class PipelineApi extends AbstractTypedClientApi<Pipeline> implements CRUDApi<String, Pipeline> {
 
@@ -34,7 +35,7 @@ public PipelineApi(StreamPipesClientConfig clientConfig) {
   }
 
   @Override
-  public Pipeline get(String pipelineId) {
+  public Optional<Pipeline> get(String pipelineId) {
     return getSingle(getBaseResourcePath().addToPath(pipelineId));
   }
 

streampipes-client/src/main/java/org/apache/streampipes/client/api/PipelineElementTemplateApi.java

@@ -22,6 +22,7 @@
 import org.apache.streampipes.model.template.PipelineElementTemplate;
 
 import java.util.List;
+import java.util.Optional;
 
 public class PipelineElementTemplateApi extends AbstractTypedClientApi<PipelineElementTemplate>
     implements CRUDApi<String, PipelineElementTemplate> {
@@ -31,7 +32,7 @@ public PipelineElementTemplateApi(StreamPipesClientConfig clientConfig) {
   }
 
   @Override
-  public PipelineElementTemplate get(String id) {
+  public Optional<PipelineElementTemplate> get(String id) {
     return getSingle(getBaseResourcePath().addToPath(id));
   }
 

streampipes-client/src/main/java/org/apache/streampipes/client/http/HttpRequest.java

@@ -22,6 +22,7 @@
 import org.apache.streampipes.client.model.StreamPipesClientConfig;
 import org.apache.streampipes.client.serializer.Serializer;
 import org.apache.streampipes.client.util.StreamPipesApiPath;
+import org.apache.streampipes.commons.exceptions.SpHttpErrorStatusCode;
 import org.apache.streampipes.commons.exceptions.SpRuntimeException;
 
 import com.fasterxml.jackson.databind.ObjectMapper;
@@ -100,14 +101,19 @@ public T executeRequest() {
       if (status.getStatusCode() == HttpStatus.SC_OK) {
         return afterRequest(serializer, response.getEntity());
       } else {
-        if (status.getStatusCode() == 401) {
-          throw new SpRuntimeException(
-              " 401 - Access to this resource is forbidden - did you provide a poper API key or client secret?");
-        } else {
-          throw new SpRuntimeException(status.getStatusCode() + " - " + status.getReasonPhrase());
+        switch (status.getStatusCode()) {
+          case HttpStatus.SC_UNAUTHORIZED:
+            throw new SpHttpErrorStatusCode(
+                " 401 - Access to this resource is forbidden - did you provide a poper API key or client secret?",
+                401);
+          case HttpStatus.SC_NOT_FOUND:
+            throw new SpHttpErrorStatusCode(" 404 - The requested resource could not be found.", 404);
+          default:
+            throw new SpHttpErrorStatusCode(status.getStatusCode() + " - " + status.getReasonPhrase(),
+                status.getStatusCode());
         }
       }
-    } catch (IOException | SpRuntimeException e) {
+    } catch (IOException e) {
       throw new SpRuntimeException(
           "Could not connect to the StreamPipes API - please check that StreamPipes is available", e);
     }

streampipes-commons/src/main/java/org/apache/streampipes/commons/exceptions/SpHttpErrorStatusCode.java

@@ -0,0 +1,39 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF 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.streampipes.commons.exceptions;
+
+public class SpHttpErrorStatusCode extends SpRuntimeException {
+
+  private static final long serialVersionUID = 2289470758226670270L;
+  private Integer httpStatusCode;
+
+  /**
+   * Creates a new Exception with the given message and null as the cause.
+   *
+   * @param message The exception message
+   */
+  public SpHttpErrorStatusCode(String message, Integer httpStatusCode) {
+    super(message);
+    this.httpStatusCode = httpStatusCode;
+  }
+
+  public Integer getHttpStatusCode() {
+    return httpStatusCode;
+  }
+}

streampipes-rest-extensions/pom.xml

@@ -75,4 +75,4 @@
         </plugins>
     </build>
 
-</project>
+</project>

streampipes-rest-shared/pom.xml

@@ -17,7 +17,8 @@
   ~
   -->
 
-<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
     <parent>
         <artifactId>streampipes-parent</artifactId>
         <groupId>org.apache.streampipes</groupId>

streampipes-rest-shared/src/main/java/org/apache/streampipes/rest/shared/impl/AbstractSharedRestInterface.java

@@ -31,12 +31,15 @@ protected <T> Response badRequest(T entity) {
     return error(entity, 400);
   }
 
+  protected <T> Response notFound(T entity) {
+    return error(entity, 404);
+  }
+
   protected <T> Response serverError(T entity) {
     return error(entity, 500);
   }
 
-  protected <T> Response error(T entity,
-                               Integer statusCode) {
+  protected <T> Response error(T entity, Integer statusCode) {
     return Response
         .status(statusCode)
         .entity(entity)

streampipes-rest/pom.xml

@@ -159,7 +159,12 @@
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-checkstyle-plugin</artifactId>
+                <configuration>
+                    <propertyExpansion>
+                        checkstyle.config.base.path=${project.parent.basedir}/tools/maven
+                    </propertyExpansion>
+                </configuration>
             </plugin>
         </plugins>
     </build>
-</project>
+</project>