Merge pull request #51 from common-workflow-language/graphviz-serverside

Swap to serverside GraphViz rendering

Author: MarkRobbo

pom.xml

@@ -24,6 +24,13 @@
 		<java.version>1.8</java.version>
 	</properties>
 
+    <repositories>
+        <repository>
+            <id>jitpack.io</id>
+            <url>https://jitpack.io</url>
+        </repository>
+    </repositories>
+
 	<dependencies>
 		<dependency>
 			<groupId>org.springframework.boot</groupId>
@@ -57,6 +64,11 @@
 			<artifactId>snakeyaml</artifactId>
 			<version>1.7</version>
 		</dependency>
+        <dependency>
+            <groupId>com.github.jabbalaci</groupId>
+            <artifactId>graphviz-java-api</artifactId>
+            <version>f9bf94896776de6e98b5004e819b63fb4c15b15d</version>
+        </dependency>
         <dependency>
             <groupId>org.apache.taverna.language</groupId>
             <artifactId>taverna-robundle</artifactId>

src/main/java/org/commonwl/viewer/services/ROBundleFactory.java

@@ -53,11 +53,11 @@ public class ROBundleFactory {
     @Autowired
     public ROBundleFactory(@Value("${applicationName}") String applicationName,
                            @Value("${applicationURL}") String applicationURL,
-                           @Value("${storageLocation}") Path storageLocation,
+                           @Value("${graphvizStorage}") Path graphvizStorage,
                            WorkflowRepository workflowRepository) {
         this.applicationName = applicationName;
         this.applicationURL = applicationURL;
-        this.storageLocation = storageLocation;
+        this.storageLocation = graphvizStorage;
         this.workflowRepository = workflowRepository;
     }
 

src/main/java/org/commonwl/viewer/web/WorkflowController.java

@@ -19,6 +19,7 @@
 
 package org.commonwl.viewer.web;
 
+import com.github.jabbalaci.graphviz.GraphViz;
 import org.apache.commons.lang.StringUtils;
 import org.commonwl.viewer.domain.GithubDetails;
 import org.commonwl.viewer.domain.Workflow;
@@ -29,6 +30,7 @@
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.beans.factory.annotation.Value;
 import org.springframework.core.io.FileSystemResource;
 import org.springframework.stereotype.Controller;
 import org.springframework.validation.BindingResult;
@@ -40,6 +42,7 @@
 import javax.servlet.http.HttpServletResponse;
 import javax.validation.Valid;
 import java.io.File;
+import java.io.IOException;
 
 @Controller
 public class WorkflowController {
@@ -214,4 +217,67 @@ public FileSystemResource downloadROBundle(@PathVariable("workflowID") String wo
         logger.info("Serving download for workflow " + workflowID + " [" + bundleDownload.toString() + "]");
         return new FileSystemResource(bundleDownload);
     }
+
+    /**
+     * Download a generated DOT graph for a workflow as an svg
+     * @param workflowID The ID of the workflow to download the graph for
+     */
+    @RequestMapping(value = "/workflows/{workflowID}/graph/svg",
+                    method = RequestMethod.GET,
+                    produces = "image/svg+xml")
+    @ResponseBody
+    public FileSystemResource getGraphAsSvg(@Value("${graphvizStorage}") String graphvizStorage,
+                                            @PathVariable("workflowID") String workflowID) throws IOException {
+
+        // Get workflow from database
+        Workflow workflowModel = workflowRepository.findOne(workflowID);
+
+        // 404 error if workflow does not exist
+        if (workflowModel == null) {
+            throw new WorkflowNotFoundException();
+        }
+
+        // Generate graphviz image if it does not already exist
+        File out = new File(graphvizStorage + "/" + workflowID + ".svg");
+        if (!out.exists()) {
+            GraphViz gv = new GraphViz();
+            gv.decreaseDpi();
+            gv.decreaseDpi();
+            gv.decreaseDpi();
+            gv.writeGraphToFile(gv.getGraph(workflowModel.getDotGraph(), "svg", "dot"), out.getAbsolutePath());
+        }
+
+        // Output the graph image
+        return new FileSystemResource(out);
+    }
+
+    /**
+     * Download a generated DOT graph for a workflow as a png
+     * @param workflowID The ID of the workflow to download the graph for
+     */
+    @RequestMapping(value = "/workflows/{workflowID}/graph/png",
+            method = RequestMethod.GET,
+            produces = "image/png")
+    @ResponseBody
+    public FileSystemResource getGraphAsPng(@Value("${graphvizStorage}") String graphvizStorage,
+                                            @PathVariable("workflowID") String workflowID) throws IOException {
+
+        // Get workflow from database
+        Workflow workflowModel = workflowRepository.findOne(workflowID);
+
+        // 404 error if workflow does not exist
+        if (workflowModel == null) {
+            throw new WorkflowNotFoundException();
+        }
+
+        // Generate graphviz image if it does not already exist
+        File out = new File(graphvizStorage + "/" + workflowID + ".png");
+        if (!out.exists()) {
+            GraphViz gv = new GraphViz();
+            gv.writeGraphToFile(gv.getGraph(workflowModel.getDotGraph(), "png", "dot"), out.getAbsolutePath());
+        }
+
+        // Output the graph image
+        return new FileSystemResource(out);
+    }
 }

src/main/resources/application.properties

@@ -7,7 +7,10 @@ applicationName = Common Workflow Language Viewer
 applicationURL = http://view.commonwl.org
 
 # Path to a directory in which the RO Bundles will be stored
-storageLocation = /tmp
+bundleStorage = /tmp
+
+# Path to a directory in which graphviz images will be stored
+graphvizStorage = /tmp
 
 # How long to cache workflows in days before checking for changes via Github
 cacheDays = 1