feat(engine-rest): Add process instance comments rest api

Related to CAM-14446, camunda#1834

engine-rest/engine-rest-openapi/src/main/templates/paths/process-instance/{id}/comment/get.ftl

@@ -0,0 +1,77 @@
+<#macro endpoint_macro docsUrl="">
+{
+
+  <@lib.endpointInfo
+      id = "getProcessInstanceComments"
+      tag = "Process Instance"
+      summary = "Get Process Instance Comments"
+      desc = "Gets the comments for a process instance by id." />
+
+  "parameters" : [
+
+    <@lib.parameter
+        name = "id"
+        location = "path"
+        type = "string"
+        required = true
+        last = true
+        desc = "The id of the process instance to retrieve the comments for." />
+
+  ],
+
+  "responses" : {
+
+    <@lib.response
+        code = "200"
+        dto = "CommentDto"
+        array = true
+        desc = "Request successful."
+        examples = ['"example-1": {
+                       "summary": "GET /process-instance/aProcessInstanceId/comment",
+                       "value": [
+                         {
+                           "id": "commentId",
+                           "userId": "userId",
+                           "taskId": "aTaskId",
+                           "processInstanceId": "aProcessInstanceId",
+                           "time": "2013-01-02T21:37:03.764+0200",
+                           "message": "message",
+                           "removalTime": "2018-02-10T14:33:19.000+0200",
+                           "rootProcessInstanceId": "aRootProcessInstanceId"
+                         },
+                         {
+                           "id": "anotherCommentId",
+                           "userId": "anotherUserId",
+                           "taskId": "aTaskId",
+                           "processInstanceId": "aProcessInstanceId",
+                           "time": "2013-02-23T20:37:43.975+0200",
+                           "message": "anotherMessage",
+                           "removalTime": "2018-02-10T14:33:19.000+0200",
+                           "rootProcessInstanceId": "aRootProcessInstanceId"
+                         },
+                         {
+                           "id": "yetAnotherCommentId",
+                           "userId": "yetAnotherUserId",
+                           "taskId": "aTaskId",
+                           "processInstanceId": "aProcessInstanceId",
+                           "time": "2013-04-21T10:15:23.764+0200",
+                           "message": "yetAnotherMessage",
+                           "removalTime": "2018-02-10T14:33:19.000+0200",
+                           "rootProcessInstanceId": "aRootProcessInstanceId"
+                         }
+                       ]
+                     }'
+        ] />
+
+    <@lib.response
+        code = "404"
+        dto = "ExceptionDto"
+        last = true
+        desc = "No process instance exists for the given process instance id. See the
+                [Introduction](${docsUrl}/reference/rest/overview/#error-handling)
+                for the error response format." />
+
+  }
+}
+
+</#macro>

engine-rest/engine-rest/src/main/java/org/camunda/bpm/engine/rest/sub/runtime/ProcessInstanceCommentResource.java

@@ -0,0 +1,33 @@
+/*
+ * Copyright Camunda Services GmbH and/or licensed to Camunda Services GmbH
+ * under one or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information regarding copyright
+ * ownership. Camunda licenses this file to you under the Apache License,
+ * Version 2.0; 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.camunda.bpm.engine.rest.sub.runtime;
+
+import java.util.List;
+
+import javax.ws.rs.GET;
+import javax.ws.rs.Produces;
+import javax.ws.rs.core.MediaType;
+
+import org.camunda.bpm.engine.rest.dto.task.CommentDto;
+
+public interface ProcessInstanceCommentResource {
+
+  @GET
+  @Produces(MediaType.APPLICATION_JSON)
+  List<CommentDto> getComments();
+
+}

engine-rest/engine-rest/src/main/java/org/camunda/bpm/engine/rest/sub/runtime/ProcessInstanceResource.java

@@ -69,4 +69,7 @@ void deleteProcessInstance(@QueryParam("skipCustomListeners") @DefaultValue("fal
   @Consumes(MediaType.APPLICATION_JSON)
   @Produces(MediaType.APPLICATION_JSON)
   BatchDto modifyProcessInstanceAsync(ProcessInstanceModificationDto dto);
+
+  @Path("/comment")
+  ProcessInstanceCommentResource getProcessInstanceCommentResource();
 }

engine-rest/engine-rest/src/main/java/org/camunda/bpm/engine/rest/sub/runtime/impl/ProcessInstanceCommentResourceImpl.java

@@ -0,0 +1,82 @@
+/*
+ * Copyright Camunda Services GmbH and/or licensed to Camunda Services GmbH
+ * under one or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information regarding copyright
+ * ownership. Camunda licenses this file to you under the Apache License,
+ * Version 2.0; 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.camunda.bpm.engine.rest.sub.runtime.impl;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
+import javax.ws.rs.core.Response.Status;
+
+import org.camunda.bpm.engine.IdentityService;
+import org.camunda.bpm.engine.ProcessEngine;
+import org.camunda.bpm.engine.history.HistoricProcessInstance;
+import org.camunda.bpm.engine.impl.cfg.ProcessEngineConfigurationImpl;
+import org.camunda.bpm.engine.impl.identity.Authentication;
+import org.camunda.bpm.engine.rest.dto.task.CommentDto;
+import org.camunda.bpm.engine.rest.exception.InvalidRequestException;
+import org.camunda.bpm.engine.rest.sub.runtime.ProcessInstanceCommentResource;
+import org.camunda.bpm.engine.task.Comment;
+
+public class ProcessInstanceCommentResourceImpl implements ProcessInstanceCommentResource {
+
+  private ProcessEngine engine;
+  private String processInstanceId;
+
+  public ProcessInstanceCommentResourceImpl(ProcessEngine engine, String processInstanceId) {
+    this.engine = engine;
+    this.processInstanceId = processInstanceId;
+  }
+
+  public List<CommentDto> getComments() {
+    if (!isHistoryEnabled()) {
+      return Collections.emptyList();
+    }
+
+    ensureProcessInstanceExists(Status.NOT_FOUND);
+
+    List<Comment> processInstanceComments = engine.getTaskService().getProcessInstanceComments(processInstanceId);
+
+    List<CommentDto> comments = new ArrayList<CommentDto>();
+    for (Comment comment : processInstanceComments) {
+      comments.add(CommentDto.fromComment(comment));
+    }
+
+    return comments;
+  }
+
+  private boolean isHistoryEnabled() {
+    IdentityService identityService = engine.getIdentityService();
+    Authentication currentAuthentication = identityService.getCurrentAuthentication();
+    try {
+      identityService.clearAuthentication();
+      int historyLevel = engine.getManagementService().getHistoryLevel();
+      return historyLevel > ProcessEngineConfigurationImpl.HISTORYLEVEL_NONE;
+    } finally {
+      identityService.setAuthentication(currentAuthentication);
+    }
+  }
+
+  private void ensureProcessInstanceExists(Status status) {
+    HistoricProcessInstance historicProcessInstance = engine.getHistoryService().createHistoricProcessInstanceQuery()
+        .processInstanceId(processInstanceId).singleResult();
+    if (historicProcessInstance == null) {
+      throw new InvalidRequestException(status, "No process instance found for id " + processInstanceId);
+    }
+  }
+
+}

engine-rest/engine-rest/src/main/java/org/camunda/bpm/engine/rest/sub/runtime/impl/ProcessInstanceResourceImpl.java

@@ -32,6 +32,7 @@
 import org.camunda.bpm.engine.rest.dto.runtime.modification.ProcessInstanceModificationDto;
 import org.camunda.bpm.engine.rest.exception.InvalidRequestException;
 import org.camunda.bpm.engine.rest.sub.VariableResource;
+import org.camunda.bpm.engine.rest.sub.runtime.ProcessInstanceCommentResource;
 import org.camunda.bpm.engine.rest.sub.runtime.ProcessInstanceResource;
 import org.camunda.bpm.engine.runtime.ActivityInstance;
 import org.camunda.bpm.engine.runtime.ProcessInstance;
@@ -154,4 +155,10 @@ public BatchDto modifyProcessInstanceAsync(ProcessInstanceModificationDto dto) {
 
     throw new InvalidRequestException(Status.BAD_REQUEST, "The provided instuctions are invalid.");
   }
+
+  @Override
+  public ProcessInstanceCommentResource getProcessInstanceCommentResource() {
+    return new ProcessInstanceCommentResourceImpl(engine, processInstanceId);
+  }
+
 }