feat(Viewer): fire <import.*> events

lib/Viewer.js

@@ -185,21 +185,19 @@ Viewer.prototype.invoke = function(fn) {
 
 Viewer.prototype.importDefinitions = function(definitions, done) {
 
-  var diagram = this.diagram;
-
   // use try/catch to not swallow synchronous exceptions
   // that may be raised during model parsing
   try {
-    if (diagram) {
+    if (this.diagram) {
       this.clear();
     }
 
-    this.diagram = diagram = this._createDiagram(this.options);
     this.definitions = definitions;
+    this.diagram = this._createDiagram(this.options);
 
-    this._init(diagram);
+    this._init(this.diagram);
 
-    Importer.importBpmnDiagram(diagram, definitions, done);
+    Importer.importBpmnDiagram(this.diagram, definitions, done);
   } catch (e) {
     done(e);
   }

lib/import/Importer.js

@@ -14,7 +14,8 @@ var BpmnTreeWalker = require('./BpmnTreeWalker');
  */
 function importBpmnDiagram(diagram, definitions, done) {
 
-  var importer = diagram.get('bpmnImporter');
+  var importer = diagram.get('bpmnImporter'),
+      eventBus = diagram.get('eventBus');
 
   var warnings = [];
 
@@ -35,10 +36,19 @@ function importBpmnDiagram(diagram, definitions, done) {
 
   var walker = new BpmnTreeWalker(visitor);
 
-  // import
-  walker.handleDefinitions(definitions);
+  try {
+    eventBus.fire('import.start');
 
-  done(null, warnings);
+    // import
+    walker.handleDefinitions(definitions);
+
+    eventBus.fire('import.success', warnings);
+
+    done(null, warnings);
+  } catch (e) {
+    eventBus.fire('import.error', e);
+    done(e);
+  }
 }
 
 module.exports.importBpmnDiagram = importBpmnDiagram;

test/spec/ViewerSpec.js

@@ -48,6 +48,45 @@ describe('viewer', function() {
   });
 
 
+  describe('import events', function() {
+
+    iit('should fire <import.*> events', function(done) {
+
+      // given
+      var viewer = new Viewer({ container: container });
+
+      var xml = fs.readFileSync('test/fixtures/bpmn/empty-definitions.bpmn', 'utf8');
+
+      var events = [];
+
+      viewer.on('import.start', function() {
+        events.push('import.start');
+      });
+
+      viewer.on('import.success', function() {
+        events.push('import.success');
+      });
+
+      viewer.on('import.error', function() {
+        events.push('import.error');
+      });
+
+      // when
+      viewer.importXML(xml, function(err) {
+
+        // then
+        expect(events).toEqual([
+          'import.start',
+          'import.success'
+        ]);
+
+        done(err);
+      });
+    });
+
+  });
+
+
   describe('error handling', function() {
 
     it('should handle non-bpmn input', function(done) {