feat(import): deferred import connections

lib/import/BpmnTreeWalker.js

@@ -12,6 +12,10 @@ function BpmnTreeWalker(handler) {
   // list of containers already walked
   var handledProcesses = [];
 
+  // list of elements to handle deferred to ensure
+  // prerequisites are drawn
+  var deferred = [];
+
   ///// Helpers /////////////////////////////////
 
   function contextual(fn, ctx) {
@@ -42,9 +46,13 @@ function BpmnTreeWalker(handler) {
   }
 
   function visitIfDi(element, ctx) {
+    try {
       if (element.di) {
         return visit(element, ctx);
       }
+    } catch (e) {
+      logError(e.message, { element: element, error: e });
+    }
   }
 
   function logError(message, context) {
@@ -122,6 +130,13 @@ function BpmnTreeWalker(handler) {
     } else {
       throw new Error('unsupported root element for bpmndi:Diagram <' + rootElement.$type + '>');
     }
+
+    // handle all deferred elements
+    handleDeferred(deferred);
+  }
+
+  function handleDeferred(deferred) {
+    _.forEach(deferred, function(d) { d(); });
   }
 
   function handleProcess(process, context) {
@@ -202,13 +217,6 @@ function BpmnTreeWalker(handler) {
     if (is(flowNode, 'bpmn:SubProcess')) {
       handleSubProcess(flowNode, childCtx || context);
     }
-
-    if (is(flowNode, 'bpmn:Activity')) {
-      _.forEach(flowNode.dataInputAssociations, contextual(handleDataAssociation, null));
-      _.forEach(flowNode.dataOutputAssociations, contextual(handleDataAssociation, null));
-
-      handleIoSpecification(flowNode.ioSpecification, context);
-    }
   }
 
   function handleSequenceFlow(sequenceFlow, context) {
@@ -219,7 +227,7 @@ function BpmnTreeWalker(handler) {
     visitIfDi(dataObject, context);
   }
 
-  function handleBoundaryElement(dataObject, context) {
+  function handleBoundaryEvent(dataObject, context) {
     visitIfDi(dataObject, context);
   }
 
@@ -255,41 +263,48 @@ function BpmnTreeWalker(handler) {
   }
 
   function handleNonFlowNodes(flowElements, context) {
-    var sequenceFlows = [];
-    var boundaryEvents = [];
-
     _.forEach(flowElements, function(e) {
       if (is(e, 'bpmn:SequenceFlow')) {
-        sequenceFlows.push(e);
+        deferred.push(function() {
+          handleSequenceFlow(e, context);
+        });
+      } else if (is(e, 'bpmn:BoundaryEvent')) {
+        deferred.unshift(function() {
+          handleBoundaryEvent(e, context);
+        });
       } else if (is(e, 'bpmn:DataObject')) {
         // SKIP (assume correct referencing via DataObjectReference)
       } else if (is(e, 'bpmn:DataStoreReference')) {
         handleDataElement(e, context);
       } else if (is(e, 'bpmn:DataObjectReference')) {
         handleDataElement(e, context);
-      } else if (is(e, 'bpmn:BoundaryEvent')) {
-        boundaryEvents.push(e);
       }
     });
-
-    // handle boundary events
-    _.forEach(boundaryEvents, contextual(handleBoundaryElement, context));
-
-    // handle SequenceFlows
-    _.forEach(sequenceFlows, contextual(handleSequenceFlow, context));
   }
 
   function handleFlowElements(flowElements, context) {
-    var sequenceFlows = [];
-    var boundaryEvents = [];
-
     _.forEach(flowElements, function(e) {
       if (is(e, 'bpmn:SequenceFlow')) {
-        sequenceFlows.push(e);
+        deferred.push(function() {
+          handleSequenceFlow(e, context);
+        });
       } else if (is(e, 'bpmn:BoundaryEvent')) {
-        boundaryEvents.push(e);
+        deferred.unshift(function() {
+          handleBoundaryEvent(e, context);
+        });
       } else if (is(e, 'bpmn:FlowNode')) {
         handleFlowNode(e, context);
+
+        if (is(e, 'bpmn:Activity')) {
+
+          handleIoSpecification(e.ioSpecification, context);
+
+          // defer handling of associations
+          deferred.push(function() {
+            _.forEach(e.dataInputAssociations, contextual(handleDataAssociation, context));
+            _.forEach(e.dataOutputAssociations, contextual(handleDataAssociation, context));
+          });
+        }
       } else if (is(e, 'bpmn:DataObject')) {
         // SKIP (assume correct referencing via DataObjectReference)
       } else if (is(e, 'bpmn:DataStoreReference')) {
@@ -302,12 +317,6 @@ function BpmnTreeWalker(handler) {
           { element: e, context: context });
       }
     });
-
-    // handle boundary events
-    _.forEach(boundaryEvents, contextual(handleBoundaryElement, context));
-
-    // handle SequenceFlows
-    _.forEach(sequenceFlows, contextual(handleSequenceFlow, context));
   }
 
   function handleParticipant(participant, context) {

test/spec/browser/import/ImporterSpec.js

@@ -112,8 +112,8 @@ describe('import - importer', function() {
           { type: 'add', semantic: 'SubProcess_1', di: '_BPMNShape_SubProcess_2', diagramElement: 'SubProcess_1' },
           { type: 'add', semantic: 'StartEvent_1', di: '_BPMNShape_StartEvent_2', diagramElement: 'StartEvent_1' },
           { type: 'add', semantic: 'Task_1', di: '_BPMNShape_Task_2', diagramElement: 'Task_1' },
-          { type: 'add', semantic: 'SequenceFlow_1', di: 'BPMNEdge_SequenceFlow_1', diagramElement: 'SequenceFlow_1' },
           { type: 'add', semantic: 'EndEvent_1', di: '_BPMNShape_EndEvent_2', diagramElement: 'EndEvent_1' },
+          { type: 'add', semantic: 'SequenceFlow_1', di: 'BPMNEdge_SequenceFlow_1', diagramElement: 'SequenceFlow_1' },
           { type: 'add', semantic: 'SequenceFlow_2', di: 'BPMNEdge_SequenceFlow_2', diagramElement: 'SequenceFlow_2' }
         ]);