connect visualization factory with restapi

zeppelin-server/src/main/java/org/apache/zeppelin/rest/HeliumRestApi.java

@@ -17,12 +17,11 @@
 
 package org.apache.zeppelin.rest;
 
+import com.github.eirslett.maven.plugins.frontend.lib.TaskRunnerException;
 import com.google.gson.Gson;
 import org.apache.commons.io.FileUtils;
 import org.apache.zeppelin.helium.Helium;
-import org.apache.zeppelin.helium.HeliumApplicationFactory;
 import org.apache.zeppelin.helium.HeliumPackage;
-import org.apache.zeppelin.helium.HeliumVisualizationFactory;
 import org.apache.zeppelin.notebook.Note;
 import org.apache.zeppelin.notebook.Notebook;
 import org.apache.zeppelin.notebook.Paragraph;
@@ -34,6 +33,7 @@ import javax.ws.rs.*;
 import javax.ws.rs.core.Response;
 import java.io.File;
 import java.io.IOException;
+import java.util.List;
 
 /**
  * Helium Rest Api
@@ -44,21 +44,14 @@ public class HeliumRestApi {
   Logger logger = LoggerFactory.getLogger(HeliumRestApi.class);
 
   private Helium helium;
-  private HeliumApplicationFactory applicationFactory;
-  private HeliumVisualizationFactory visualizationFactory;
   private Notebook notebook;
   private Gson gson = new Gson();
 
   public HeliumRestApi() {
   }
 
-  public HeliumRestApi(Helium helium,
-                       HeliumApplicationFactory heliumApplicationFactory,
-                       HeliumVisualizationFactory heliumVisualizationFactory,
-                       Notebook notebook) {
+  public HeliumRestApi(Helium helium, Notebook notebook) {
     this.helium  = helium;
-    this.applicationFactory = heliumApplicationFactory;
-    this.visualizationFactory = heliumVisualizationFactory;
     this.notebook = notebook;
   }
 
@@ -108,7 +101,7 @@ public class HeliumRestApi {
     }
     HeliumPackage pkg = gson.fromJson(heliumPackage, HeliumPackage.class);
 
-    String appId = applicationFactory.loadAndRun(pkg, paragraph);
+    String appId = helium.getApplicationFactory().loadAndRun(pkg, paragraph);
     return new JsonResponse(Response.Status.OK, "", appId).build();
   }
 
@@ -116,12 +109,54 @@ public class HeliumRestApi {
   @Path("visualizations/load")
   @Produces("text/javascript")
   public Response visualizationLoad() {
+    List<HeliumPackage> packages = helium.getVisualizationPackagesToBundle();
+
     try {
-      String visBundle = FileUtils.readFileToString(new File("/tmp/npm/vis.bundle.js"));
-      return Response.ok(visBundle).build();
+      File bundle = helium.getVisualizationFactory().getCurrentBundle();
+      if (bundle == null) {
+        return Response.ok().build();
+      } else {
+        String visBundle = FileUtils.readFileToString(bundle);
+        return Response.ok(visBundle).build();
+      }
+    } catch (Exception e) {
+      logger.error(e.getMessage(), e);
+
+      // returning error will prevent zeppelin front-end render any notebook.
+      // visualization load fail doesn't need to block notebook rendering work.
+      // so it's better return ok instead of any error.
+      return Response.ok().build();
+    }
+  }
+
+  @POST
+  @Path("enable/{packageName}")
+  public Response enablePackage(@PathParam("packageName") String packageName,
+                                String artifact) {
+    try {
+      helium.enable(packageName, artifact);
+      return new JsonResponse(Response.Status.OK).build();
     } catch (IOException e) {
       logger.error(e.getMessage(), e);
-      return Response.serverError().build();
+      return new JsonResponse(Response.Status.INTERNAL_SERVER_ERROR).build();
+    } catch (TaskRunnerException e) {
+      logger.error(e.getMessage(), e);
+      return new JsonResponse(Response.Status.INTERNAL_SERVER_ERROR).build();
+    }
+  }
+
+  @POST
+  @Path("disable/{packageName}")
+  public Response enablePackage(@PathParam("packageName") String packageName) {
+    try {
+      helium.disable(packageName);
+      return new JsonResponse(Response.Status.OK).build();
+    } catch (IOException e) {
+      logger.error(e.getMessage(), e);
+      return new JsonResponse(Response.Status.INTERNAL_SERVER_ERROR).build();
+    } catch (TaskRunnerException e) {
+      logger.error(e.getMessage(), e);
+      return new JsonResponse(Response.Status.INTERNAL_SERVER_ERROR).build();
     }
   }
 }

zeppelin-server/src/main/java/org/apache/zeppelin/server/ZeppelinServer.java

@@ -83,8 +83,6 @@ public class ZeppelinServer extends Application {
   public static Server jettyWebServer;
   public static NotebookServer notebookWsServer;
   public static Helium helium;
-  public static HeliumApplicationFactory heliumApplicationFactory;
-  public static HeliumVisualizationFactory heliumVisualizationFactory;
 
   private SchedulerFactory schedulerFactory;
   private InterpreterFactory replFactory;
@@ -100,11 +98,16 @@ public class ZeppelinServer extends Application {
     this.depResolver = new DependencyResolver(
         conf.getString(ConfVars.ZEPPELIN_INTERPRETER_LOCALREPO));
 
-    this.helium = new Helium(conf.getHeliumConfPath(), conf.getHeliumDefaultLocalRegistryPath());
-    this.heliumApplicationFactory = new HeliumApplicationFactory();
-    this.heliumVisualizationFactory = new HeliumVisualizationFactory(
+    HeliumApplicationFactory heliumApplicationFactory = new HeliumApplicationFactory();
+    HeliumVisualizationFactory heliumVisualizationFactory = new HeliumVisualizationFactory(
         new File(conf.getRelativeDir(ConfVars.ZEPPELIN_DEP_LOCALREPO)));
 
+    this.helium = new Helium(
+        conf.getHeliumConfPath(),
+        conf.getHeliumDefaultLocalRegistryPath(),
+        heliumVisualizationFactory,
+        heliumApplicationFactory);
+
 
     this.schedulerFactory = new SchedulerFactory();
     this.replFactory = new InterpreterFactory(conf, notebookWsServer,
@@ -338,8 +341,7 @@ public class ZeppelinServer extends Application {
     NotebookRepoRestApi notebookRepoApi = new NotebookRepoRestApi(notebookRepo, notebookWsServer);
     singletons.add(notebookRepoApi);
 
-    HeliumRestApi heliumApi = new HeliumRestApi(helium, heliumApplicationFactory,
-        heliumVisualizationFactory, notebook);
+    HeliumRestApi heliumApi = new HeliumRestApi(helium, notebook);
     singletons.add(heliumApi);
 
     InterpreterRestApi interpreterApi = new InterpreterRestApi(replFactory);

zeppelin-web/src/app/helium/helium.controller.js

@@ -19,13 +19,33 @@
   HeliumCtrl.$inject = ['$scope', '$rootScope', '$http', 'baseUrlSrv', 'ngToast'];
 
   function HeliumCtrl($scope, $rootScope, $http, baseUrlSrv, ngToast) {
-    $scope.packageInfos = [];
+    $scope.packageInfos = {};
+    $scope.defaultVersions = {};
+
+    var buildDefaultVersionListToDisplay = function(packageInfos) {
+      var defaultVersions = {};
+      // show enabled version if any version of package is enabled
+      for (var name in packageInfos) {
+        var pkgs = packageInfos[name];
+        for (var pkg in pkgs) {
+          if (pkg.enabled) {
+            defaultVersions[name] = pkg;
+          }
+        }
+
+        // show first available version if package is not enabled
+        if (!defaultVersions[name]) {
+          defaultVersions[name] = pkgs[0];
+        }
+      }
+      $scope.defaultVersions = defaultVersions;
+    };
 
     var getAllPackageInfo = function() {
       $http.get(baseUrlSrv.getRestApiBase() + '/helium/all').
         success(function(data, status) {
-          console.log('Packages %o', data);
           $scope.packageInfos = data.body;
+          buildDefaultVersionListToDisplay($scope.packageInfos);
         }).
         error(function(data, status) {
           console.log('Can not load package info %o %o', status, data);
@@ -37,5 +57,25 @@
     };
 
     init();
+
+    $scope.enable = function(name, artifact) {
+      $http.post(baseUrlSrv.getRestApiBase() + '/helium/enable/' + name, artifact).
+        success(function(data, status) {
+          getAllPackageInfo();
+        }).
+        error(function(data, status) {
+          console.log('Failed to enable package %o %o', name, artifact);
+        });
+    };
+
+    $scope.disable = function(name) {
+      $http.post(baseUrlSrv.getRestApiBase() + '/helium/disable/' + name).
+        success(function(data, status) {
+          getAllPackageInfo();
+        }).
+        error(function(data, status) {
+          console.log('Failed to disable package %o', name);
+        });
+    };
   }
 })();

zeppelin-web/src/app/helium/helium.html

@@ -25,21 +25,23 @@ limitations under the License.
 
 <div class="box width-full">
   <div class="row"
-       ng-repeat="packageInfo in packageInfos"
+       ng-repeat="(pkgName, pkgInfo) in defaultVersions"
        style="margin-bottom:20px">
     <div class="col-md-12">
       <div style="height:25px">
         <div style="float:left;width:20px;height:20px"
-             ng-bind-html=packageInfo.pkg.icon></div>
-        <b style="float:left">{{packageInfo.pkg.name}}</b>
-        <div ng-show="!packageInfo.enabled"
+             ng-bind-html=pkgInfo.pkg.icon></div>
+        <b style="float:left">{{pkgName}}</b>
+        <div ng-show="!pkgInfo.enabled"
+             ng-click="enable(pkgName, pkgInfo.pkg.artifact)"
              class="btn btn-success btn-xs"
              style="float:right">Enable</div>
-        <div ng-show="packageInfo.enabled"
+        <div ng-show="pkgInfo.enabled"
+             ng-click="disable(pkgName)"
              class="btn btn-info btn-xs"
              style="float:right">Disable</div>
       </div>
-      {{packageInfo.pkg.description}}
+      {{pkgInfo.pkg.description}}
     </div>
   </div>
 </div>

zeppelin-web/src/index.js

@@ -45,6 +45,7 @@ import './app/notebook/paragraph/paragraph.controller.js';
 import './app/notebook/paragraph/result/result.controller.js';
 import './app/search/result-list.controller.js';
 import './app/notebookRepos/notebookRepos.controller.js';
+import './app/helium/helium.controller.js';
 import './components/arrayOrderingSrv/arrayOrdering.service.js';
 import './components/clipboard/clipboard.controller.js';
 import './components/navbar/navbar.controller.js';

zeppelin-zengine/src/main/java/org/apache/zeppelin/helium/Helium.java

@@ -16,6 +16,7 @@
  */
 package org.apache.zeppelin.helium;
 
+import com.github.eirslett.maven.plugins.frontend.lib.TaskRunnerException;
 import com.google.gson.Gson;
 import com.google.gson.GsonBuilder;
 import org.apache.commons.io.FileUtils;
@@ -32,10 +33,7 @@ import java.io.File;
 import java.io.IOException;
 import java.net.URI;
 import java.net.URISyntaxException;
-import java.util.HashMap;
-import java.util.LinkedList;
-import java.util.List;
-import java.util.Map;
+import java.util.*;
 
 /**
  * Manages helium packages
@@ -48,10 +46,19 @@ public class Helium {
   private final String heliumConfPath;
   private final String defaultLocalRegistryPath;
   private final Gson gson;
+  private final HeliumVisualizationFactory visualizationFactory;
+  private final HeliumApplicationFactory applicationFactory;
 
-  public Helium(String heliumConfPath, String defaultLocalRegistryPath) throws IOException {
+  public Helium(
+      String heliumConfPath,
+      String defaultLocalRegistryPath,
+      HeliumVisualizationFactory visualizationFactory,
+      HeliumApplicationFactory applicationFactory)
+      throws IOException, TaskRunnerException {
     this.heliumConfPath = heliumConfPath;
     this.defaultLocalRegistryPath = defaultLocalRegistryPath;
+    this.visualizationFactory = visualizationFactory;
+    this.applicationFactory = applicationFactory;
 
     GsonBuilder builder = new GsonBuilder();
     builder.setPrettyPrinting();
@@ -60,6 +67,7 @@ public class Helium {
     gson = builder.create();
 
     heliumConf = loadConf(heliumConfPath);
+    visualizationFactory.bundle(getVisualizationPackagesToBundle());
   }
 
   /**
@@ -83,6 +91,14 @@ public class Helium {
     }
   }
 
+  public HeliumApplicationFactory getApplicationFactory() {
+    return applicationFactory;
+  }
+
+  public HeliumVisualizationFactory getVisualizationFactory() {
+    return visualizationFactory;
+  }
+
   private synchronized HeliumConf loadConf(String path) throws IOException {
     File heliumConfFile = new File(path);
     if (!heliumConfFile.isFile()) {
@@ -116,30 +132,92 @@ public class Helium {
     FileUtils.writeStringToFile(heliumConfFile, jsonString);
   }
 
-  public List<HeliumPackageSearchResult> getAllPackageInfo() {
-    List<HeliumPackageSearchResult> list = new LinkedList<>();
+  public Map<String, List<HeliumPackageSearchResult>> getAllPackageInfo() {
+    Map<String, String> enabledPackageInfo = heliumConf.getEnabledPackages();
+
+    Map<String, List<HeliumPackageSearchResult>> map = new HashMap<>();
     synchronized (registry) {
       for (HeliumRegistry r : registry) {
         try {
           for (HeliumPackage pkg : r.getAll()) {
-            list.add(new HeliumPackageSearchResult(r.name(), pkg));
+            String name = pkg.getName();
+            String artifact = enabledPackageInfo.get(name);
+            boolean enabled = (artifact != null && artifact.equals(pkg.getArtifact()));
+
+            if (!map.containsKey(name)) {
+              map.put(name, new LinkedList<HeliumPackageSearchResult>());
+            }
+            map.get(name).add(new HeliumPackageSearchResult(r.name(), pkg, enabled));
           }
         } catch (IOException e) {
           logger.error(e.getMessage(), e);
         }
       }
     }
-    return list;
+
+    // sort version (artifact)
+    for (String name : map.keySet()) {
+      List<HeliumPackageSearchResult> packages = map.get(name);
+      Collections.sort(packages, new Comparator<HeliumPackageSearchResult>() {
+        @Override
+        public int compare(HeliumPackageSearchResult o1, HeliumPackageSearchResult o2) {
+          return o1.getPkg().getArtifact().compareTo(o2.getPkg().getArtifact());
+        }
+      });
+    }
+    return map;
   }
 
-  public void enable(HeliumPackage pkg) {
+  public HeliumPackageSearchResult getPackageInfo(String name, String artifact) {
+    Map<String, List<HeliumPackageSearchResult>> infos = getAllPackageInfo();
+    List<HeliumPackageSearchResult> packages = infos.get(name);
+    if (artifact == null) {
+      return packages.get(0);
+    } else {
+      for (HeliumPackageSearchResult pkg : packages) {
+        if (pkg.getPkg().getArtifact().equals(artifact)) {
+          return pkg;
+        }
+      }
+    }
 
+    return null;
   }
 
-  public void disable(HeliumPackage pkg) {
+  public void enable(String name, String artifact) throws IOException, TaskRunnerException {
+    HeliumPackageSearchResult pkgInfo = getPackageInfo(name, artifact);
 
+    // no package found.
+    if (pkgInfo == null) {
+      return;
+    }
+
+    // enable package
+    heliumConf.enablePackage(name, artifact);
+
+    // if package is visualization, rebuild bundle
+    if (pkgInfo.getPkg().getType() == HeliumPackage.Type.VISUALIZATION) {
+      visualizationFactory.bundle(getVisualizationPackagesToBundle());
+    }
+
+    save();
   }
 
+  public void disable(String name) throws IOException, TaskRunnerException {
+    String artifact = heliumConf.getEnabledPackages().get(name);
+
+    if (artifact == null) {
+      return;
+    }
+
+    heliumConf.disablePackage(name);
+    HeliumPackageSearchResult pkg = getPackageInfo(name, artifact);
+    if (pkg == null || pkg.getPkg().getType() == HeliumPackage.Type.VISUALIZATION) {
+      visualizationFactory.bundle(getVisualizationPackagesToBundle());
+    }
+
+    save();
+  }
 
   public HeliumPackageSuggestion suggestApp(Paragraph paragraph) {
     HeliumPackageSuggestion suggestion = new HeliumPackageSuggestion();
@@ -162,20 +240,61 @@ public class Helium {
       allResources = ResourcePoolUtils.getAllResources();
     }
 
-    for (HeliumPackageSearchResult pkg : getAllPackageInfo()) {
-      ResourceSet resources = ApplicationLoader.findRequiredResourceSet(
-          pkg.getPkg().getResources(),
-          paragraph.getNote().getId(),
-          paragraph.getId(),
-          allResources);
-      if (resources == null) {
-        continue;
-      } else {
-        suggestion.addAvailablePackage(pkg);
+    for (List<HeliumPackageSearchResult> pkgs : getAllPackageInfo().values()) {
+      for (HeliumPackageSearchResult pkg : pkgs) {
+        if (pkg.getPkg().getType() == HeliumPackage.Type.APPLICATION && pkg.isEnabled()) {
+          ResourceSet resources = ApplicationLoader.findRequiredResourceSet(
+              pkg.getPkg().getResources(),
+              paragraph.getNote().getId(),
+              paragraph.getId(),
+              allResources);
+          if (resources == null) {
+            continue;
+          } else {
+            suggestion.addAvailablePackage(pkg);
+          }
+          break;
+        }
       }
     }
 
     suggestion.sort();
     return suggestion;
   }
+
+  /**
+   * Get enabled visualization packages
+   *
+   * @return ordered list of enabled visualization package
+   */
+  public List<HeliumPackage> getVisualizationPackagesToBundle() {
+    Map<String, List<HeliumPackageSearchResult>> allPackages = getAllPackageInfo();
+    List<String> visOrder = heliumConf.getVisualizationDisplayOrder();
+
+    List<HeliumPackage> orderedVisualizationPackages = new LinkedList<>();
+
+    // add enabled packages in visOrder
+    for (String name : visOrder) {
+      List<HeliumPackageSearchResult> versions = allPackages.get(name);
+      for (HeliumPackageSearchResult pkgInfo : versions) {
+        if (pkgInfo.getPkg().getType() == HeliumPackage.Type.VISUALIZATION && pkgInfo.isEnabled()) {
+          orderedVisualizationPackages.add(pkgInfo.getPkg());
+          allPackages.remove(name);
+          break;
+        }
+      }
+    }
+
+    // add enabled packages not in visOrder
+    for (List<HeliumPackageSearchResult> pkgs : allPackages.values()) {
+      for (HeliumPackageSearchResult pkg : pkgs) {
+        if (pkg.getPkg().getType() == HeliumPackage.Type.VISUALIZATION && pkg.isEnabled()) {
+          orderedVisualizationPackages.add(pkg.getPkg());
+          break;
+        }
+      }
+    }
+
+    return orderedVisualizationPackages;
+  }
 }

zeppelin-zengine/src/main/java/org/apache/zeppelin/helium/HeliumConf.java

@@ -16,8 +16,7 @@
  */
 package org.apache.zeppelin.helium;
 
-import java.util.LinkedList;
-import java.util.List;
+import java.util.*;
 
 /**
  * Helium config. This object will be persisted to conf/heliumc.conf
@@ -25,6 +24,13 @@ import java.util.List;
 public class HeliumConf {
   List<HeliumRegistry> registry = new LinkedList<>();
 
+  // enabled packages {name, version}
+  Map<String, String> enabled = Collections.synchronizedMap(new HashMap<String, String>());
+
+  // enabled visualization package display order
+  List<String> visualizationDisplayOrder = new LinkedList<>();
+
+
   public List<HeliumRegistry> getRegistry() {
     return registry;
   }
@@ -33,5 +39,35 @@ public class HeliumConf {
     this.registry = registry;
   }
 
-  // enabled visualization
+  public Map<String, String> getEnabledPackages() {
+    return new HashMap<>(enabled);
+  }
+
+  public void enablePackage(HeliumPackage pkg) {
+    enablePackage(pkg.getName(), pkg.getArtifact());
+  }
+
+  public void enablePackage(String name, String artifact) {
+    enabled.put(name, artifact);
+  }
+
+  public void disablePackage(HeliumPackage pkg) {
+    disablePackage(pkg.getName());
+  }
+
+  public void disablePackage(String name) {
+    enabled.remove(name);
+  }
+
+  public List<String> getVisualizationDisplayOrder() {
+    return visualizationDisplayOrder;
+  }
+
+  public void setVisualizationDisplayOrder(List<HeliumPackage> orderedPackageList) {
+    List<String> order = new LinkedList<>();
+    for (HeliumPackage pkg : orderedPackageList) {
+      order.add(pkg.getName());
+    }
+    visualizationDisplayOrder = order;
+  }
 }

zeppelin-zengine/src/main/java/org/apache/zeppelin/helium/HeliumPackageSearchResult.java

@@ -22,15 +22,17 @@ package org.apache.zeppelin.helium;
 public class HeliumPackageSearchResult {
   private final String registry;
   private final HeliumPackage pkg;
+  private final boolean enabled;
 
   /**
    * Create search result item
    * @param registry registry name
    * @param pkg package information
    */
-  public HeliumPackageSearchResult(String registry, HeliumPackage pkg) {
+  public HeliumPackageSearchResult(String registry, HeliumPackage pkg, boolean enabled) {
     this.registry = registry;
     this.pkg = pkg;
+    this.enabled = enabled;
   }
 
   public String getRegistry() {
@@ -40,4 +42,8 @@ public class HeliumPackageSearchResult {
   public HeliumPackage getPkg() {
     return pkg;
   }
+
+  public boolean isEnabled() {
+    return enabled;
+  }
 }

zeppelin-zengine/src/main/java/org/apache/zeppelin/helium/HeliumVisualizationFactory.java

@@ -46,6 +46,9 @@ public class HeliumVisualizationFactory {
   private File tabledataModulePath;
   private File visualizationModulePath;
 
+  String bundleCacheKey = "";
+  File currentBundle;
+
   public HeliumVisualizationFactory(
       File moduleDownloadPath,
       File tabledataModulePath,
@@ -63,6 +66,7 @@ public class HeliumVisualizationFactory {
     frontEndPluginFactory = new FrontendPluginFactory(
         workingDirectory, installDirectory);
 
+    currentBundle = new File(workingDirectory, "vis.bundle.cache.js");
     installNodeAndNpm();
   }
 
@@ -81,11 +85,12 @@ public class HeliumVisualizationFactory {
     return new ProxyConfig(proxy);
   }
 
-  public void bundle(List<HeliumPackage> pkgs) throws IOException, TaskRunnerException {
+  public File bundle(List<HeliumPackage> pkgs) throws IOException, TaskRunnerException {
     // package.json
     URL pkgUrl = Resources.getResource("helium/package.json");
     String pkgJson = Resources.toString(pkgUrl, Charsets.UTF_8);
-    StringBuffer dependencies = new StringBuffer();
+    StringBuilder dependencies = new StringBuilder();
+
     for (HeliumPackage pkg : pkgs) {
       String[] moduleNameVersion = getNpmModuleNameAndVersion(pkg);
       if (moduleNameVersion == null) {
@@ -104,6 +109,11 @@ public class HeliumVisualizationFactory {
     }
     pkgJson = pkgJson.replaceFirst("DEPENDENCIES", dependencies.toString());
 
+    // check if we can use previous bundle or not
+    if (dependencies.toString().equals(bundleCacheKey) && currentBundle.isFile()) {
+      return currentBundle;
+    }
+
     // webpack.config.js
     URL webpackConfigUrl = Resources.getResource("helium/webpack.config.js");
     String webpackConfig = Resources.toString(webpackConfigUrl, Charsets.UTF_8);
@@ -111,6 +121,7 @@ public class HeliumVisualizationFactory {
     // generate load.js
     StringBuilder loadJsImport = new StringBuilder();
     StringBuilder loadJsRegister = new StringBuilder();
+
     for (HeliumPackage pkg : pkgs) {
       String [] moduleNameVersion = getNpmModuleNameAndVersion(pkg);
       if (moduleNameVersion == null) {
@@ -146,6 +157,28 @@ public class HeliumVisualizationFactory {
 
     npmCommand("install");
     npmCommand("run bundle");
+
+    File visBundleJs = new File(workingDirectory, "vis.bundle.js");
+    if (!visBundleJs.isFile()) {
+      throw new IOException("Failed to create visualization bundle");
+    }
+
+    synchronized (this) {
+      currentBundle.delete();
+      FileUtils.moveFile(visBundleJs, currentBundle);
+      bundleCacheKey = dependencies.toString();
+    }
+    return currentBundle;
+  }
+
+  public File getCurrentBundle() {
+    synchronized (this) {
+      if (currentBundle.isFile()) {
+        return currentBundle;
+      } else {
+        return null;
+      }
+    }
   }
 
   private boolean isLocalPackage(HeliumPackage pkg) {

zeppelin-zengine/src/test/java/org/apache/zeppelin/helium/HeliumTest.java

@@ -16,6 +16,7 @@
  */
 package org.apache.zeppelin.helium;
 
+import com.github.eirslett.maven.plugins.frontend.lib.TaskRunnerException;
 import org.apache.commons.io.FileUtils;
 import org.junit.After;
 import org.junit.Before;
@@ -48,10 +49,11 @@ public class HeliumTest {
   }
 
   @Test
-  public void testSaveLoadConf() throws IOException, URISyntaxException {
+  public void testSaveLoadConf() throws IOException, URISyntaxException, TaskRunnerException {
     // given
     File heliumConf = new File(tmpDir, "helium.conf");
-    Helium helium = new Helium(heliumConf.getAbsolutePath(), localRegistryPath.getAbsolutePath());
+    Helium helium = new Helium(heliumConf.getAbsolutePath(), localRegistryPath.getAbsolutePath(),
+        null, null);
     assertFalse(heliumConf.exists());
     HeliumTestRegistry registry1 = new HeliumTestRegistry("r1", "r1");
     helium.addRegistry(registry1);
@@ -65,14 +67,16 @@ public class HeliumTest {
     assertTrue(heliumConf.exists());
 
     // then
-    Helium heliumRestored = new Helium(heliumConf.getAbsolutePath(), localRegistryPath.getAbsolutePath());
+    Helium heliumRestored = new Helium(
+        heliumConf.getAbsolutePath(), localRegistryPath.getAbsolutePath(), null, null);
     assertEquals(2, heliumRestored.getAllRegistry().size());
   }
 
   @Test
-  public void testRestoreRegistryInstances() throws IOException, URISyntaxException {
+  public void testRestoreRegistryInstances() throws IOException, URISyntaxException, TaskRunnerException {
     File heliumConf = new File(tmpDir, "helium.conf");
-    Helium helium = new Helium(heliumConf.getAbsolutePath(), localRegistryPath.getAbsolutePath());
+    Helium helium = new Helium(
+        heliumConf.getAbsolutePath(), localRegistryPath.getAbsolutePath(), null, null);
     HeliumTestRegistry registry1 = new HeliumTestRegistry("r1", "r1");
     HeliumTestRegistry registry2 = new HeliumTestRegistry("r2", "r2");
     helium.addRegistry(registry1);

zeppelin-zengine/src/test/java/org/apache/zeppelin/helium/HeliumVisualizationFactoryTest.java

@@ -30,6 +30,7 @@ import java.net.URL;
 import java.util.LinkedList;
 import java.util.List;
 
+import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
 
 public class HeliumVisualizationFactoryTest {
@@ -38,8 +39,7 @@ public class HeliumVisualizationFactoryTest {
 
   @Before
   public void setUp() throws InstallationException, TaskRunnerException {
-    //tmpDir = new File(System.getProperty("java.io.tmpdir") + "/ZeppelinLTest_" + System.currentTimeMillis());
-    tmpDir = new File("/tmp/npm");
+    tmpDir = new File(System.getProperty("java.io.tmpdir") + "/ZeppelinLTest_" + System.currentTimeMillis());
     tmpDir.mkdirs();
 
     // get module dir
@@ -91,8 +91,13 @@ public class HeliumVisualizationFactoryTest {
     );
     List<HeliumPackage> pkgs = new LinkedList<>();
     pkgs.add(pkg);
-    hvf.bundle(pkgs);
-    assertTrue(new File(tmpDir, "vis.bundle.js").isFile());
+    File bundle = hvf.bundle(pkgs);
+    assertTrue(bundle.isFile());
+    long lastModified = bundle.lastModified();
+
+    // bundle again and check if it served from cache
+    bundle = hvf.bundle(pkgs);
+    assertEquals(lastModified, bundle.lastModified());
   }
 
 
@@ -101,7 +106,6 @@ public class HeliumVisualizationFactoryTest {
     URL res = Resources.getResource("helium/webpack.config.js");
     String resDir = new File(res.getFile()).getParent();
     String localPkg = resDir + "/../../../src/test/resources/helium/vis1";
-    System.err.println("local package " + localPkg);
 
     HeliumPackage pkg = new HeliumPackage(
         HeliumPackage.Type.VISUALIZATION,
@@ -114,7 +118,7 @@ public class HeliumVisualizationFactoryTest {
     );
     List<HeliumPackage> pkgs = new LinkedList<>();
     pkgs.add(pkg);
-    hvf.bundle(pkgs);
-    assertTrue(new File(tmpDir, "vis.bundle.js").isFile());
+    File bundle = hvf.bundle(pkgs);
+    assertTrue(bundle.isFile());
   }
 }