From 35c4ec7c235944fb64f28d9421ed5727f4d6eb76 Mon Sep 17 00:00:00 2001
From: Gavin Cornwell <gavin.cornwell@alfresco.com>
Date: Wed, 22 Jun 2011 08:30:09 +0000
Subject: [PATCH] ACTVT 93: Refactored /api/workflow-instances/{id}/diagram
 REST API to extend StreamContent and use temporary file (ALF-8634)

git-svn-id: https://svn.alfresco.com/repos/alfresco-enterprise/alfresco/HEAD/root@28509 c4b6b30b-aa2e-2d43-bbcb-ca4b014f7261
---
 .../web-scripts-application-context.xml       |  1 +
 .../workflow/WorkflowInstanceDiagramGet.java  | 37 +++++++------------
 2 files changed, 14 insertions(+), 24 deletions(-)

diff --git a/config/alfresco/web-scripts-application-context.xml b/config/alfresco/web-scripts-application-context.xml
index 230a01aeea..5dda2ce57d 100644
--- a/config/alfresco/web-scripts-application-context.xml
+++ b/config/alfresco/web-scripts-application-context.xml
@@ -1070,6 +1070,7 @@
     <bean id="webscript.org.alfresco.repository.workflow.workflow-instance-diagram.get"
           class="org.alfresco.repo.web.scripts.workflow.WorkflowInstanceDiagramGet"
           parent="webscript">
+       <property name="mimetypeService" ref="MimetypeService" />
        <property name="workflowService" ref="WorkflowService" />
     </bean>
 
diff --git a/source/java/org/alfresco/repo/web/scripts/workflow/WorkflowInstanceDiagramGet.java b/source/java/org/alfresco/repo/web/scripts/workflow/WorkflowInstanceDiagramGet.java
index c06feff1a3..955fb270fd 100644
--- a/source/java/org/alfresco/repo/web/scripts/workflow/WorkflowInstanceDiagramGet.java
+++ b/source/java/org/alfresco/repo/web/scripts/workflow/WorkflowInstanceDiagramGet.java
@@ -18,17 +18,19 @@
  */
 package org.alfresco.repo.web.scripts.workflow;
 
+import java.io.File;
+import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
+import java.io.OutputStream;
 import java.util.Map;
 
 import javax.servlet.http.HttpServletResponse;
 
-import org.alfresco.repo.content.MimetypeMap;
+import org.alfresco.repo.web.scripts.content.StreamContent;
 import org.alfresco.service.cmr.workflow.WorkflowInstance;
 import org.alfresco.service.cmr.workflow.WorkflowService;
-import org.springframework.extensions.webscripts.AbstractWebScript;
-import org.springframework.extensions.webscripts.Cache;
+import org.alfresco.util.TempFileProvider;
 import org.springframework.extensions.webscripts.WebScriptException;
 import org.springframework.extensions.webscripts.WebScriptRequest;
 import org.springframework.extensions.webscripts.WebScriptResponse;
@@ -40,7 +42,7 @@ import org.springframework.util.FileCopyUtils;
  * @author Gavin Cornwell
  * @since 4.0
  */
-public class WorkflowInstanceDiagramGet extends AbstractWebScript
+public class WorkflowInstanceDiagramGet extends StreamContent
 {
     protected WorkflowService workflowService;
     
@@ -71,26 +73,13 @@ public class WorkflowInstanceDiagramGet extends AbstractWebScript
             throw new WebScriptException(HttpServletResponse.SC_NOT_FOUND, "Unable to find diagram for workflow instance with id: " + workflowInstanceId);
         }
         
-        // set mimetype for the content and the character encoding + length for the stream
-        res.setContentType(MimetypeMap.MIMETYPE_IMAGE_PNG);
-        
-        // set caching (never cache)
-        Cache cache = new Cache();
-        cache.setNeverCache(true);
-        cache.setMustRevalidate(true);
-        cache.setMaxAge(0L);
-        res.setCache(cache);
-        
-        // stream image back to client
+        // copy image data into temporary file
+        File file = TempFileProvider.createTempFile("workflow-diagram-", ".png");
         InputStream imageData = workflowService.getWorkflowImage(workflowInstanceId);
-        try
-        {
-            FileCopyUtils.copy(imageData, res.getOutputStream());     // both streams are closed
-        }
-        catch (IOException e)
-        {
-            throw new WebScriptException(HttpServletResponse.SC_INTERNAL_SERVER_ERROR, "Error occurred streaming diagram for workflow instance with id '" + 
-                        workflowInstanceId + "' " + e.getMessage());
-        }
+        OutputStream os = new FileOutputStream(file);
+        FileCopyUtils.copy(imageData, os);
+        
+        // stream temporary file back to client
+        streamContent(req, res, file, false);
     }
 }