Improved error handling which sends error messages to UI.

Author: jstnhuang

backend/server/programs.js

@@ -115,6 +115,17 @@ Runtime = function() {
     messageType: 'std_msgs/Bool',
     latch: true
   });
+  var errorTopic = new ROSLIB.Topic({
+    ros: ROS,
+    name: 'code_it/errors',
+    messageType: 'std_msgs/String'
+  });
+
+  var publishError = function(message) {
+    var msg = new ROSLIB.Message({data: message});
+    console.log('Publishing error: ' + message);
+    errorTopic.publish(msg);
+  };
 
   var onProgramEnd = function() {
     var msg = new ROSLIB.Message({data: false});
@@ -139,6 +150,11 @@ Runtime = function() {
       }
       try {
         if (interpreter.step()) {
+          var error = Robot.getError();
+          if (error) {
+            publishError(error);
+            Robot.setError('');
+          }
           var feedback = {block_id: interpreter.blockId};
           if (action.currentGoal) {
             action.sendFeedback(feedback);
@@ -154,10 +170,11 @@ Runtime = function() {
           onProgramEnd();
         }
       } catch(e) {
-        console.log('Error running program ' + program);
+        console.log('Error: ');
         console.log(e);
-        console.log(e.stack);
+        e.stack && console.log(e.stack);
         action.setAborted(e.toString()); 
+        publishError('There was an error while running the program: ' + e.toString());
         onProgramEnd();
       }
     }

backend/server/robot.js

@@ -1,5 +1,15 @@
 // The implementation of the primitives.
 Robot = function() {
+  var error = ''; // Most recent error message, empty string for no error.
+
+  var getError = function() {
+    return error;
+  }
+
+  var setError = function(message) {
+    error = message;
+  }
+
   var askMultipleChoice = Meteor.wrapAsync(function(question, choices, timeout, callback) {
     console.log('Asking: ' + question + ', choices: ' + choices);
     var client = new ROSLIB.Service({
@@ -18,12 +28,16 @@ Robot = function() {
     client.callService(request, function(result) {
       if (funcCall.isRunning) {
         funcCall.isRunning = false;
+        setError(result.error);
+        if (result.error) {
+          callback(result.error, null); // Must quit program, need user input to proceed.
+        }
         callback(null, result.choice);
       }
     }, function(error) {
       if (funcCall.isRunning) {
         funcCall.isRunning = false;
-        callback(error ? error : true, null);
+        callback(error ? error : 'Failed to ask multiple choice question.', null);
       }
     });
 
@@ -55,10 +69,13 @@ Robot = function() {
     funcCall.isRunning = true;
 
     client.callService(request, function(result) {
+        funcCall.isRunning = false;
+        setError(result.error); // Failure is probaby not critical enough to quit over.
+        callback(null, null);
     }, function(error) {
       if (funcCall.isRunning) {
         funcCall.isRunning = false;
-        callback(error ? error : true, null);
+        callback(error ? error : 'Failed to display message.', null);
       }
     });
 
@@ -69,11 +86,6 @@ Robot = function() {
           callback(null, null); // err, result
         }
       }, timeout * 1000);
-    } else {
-      if (funcCall.isRunning) {
-        funcCall.isRunning = false;
-        callback(null, null);
-      }
     }
   });
 
@@ -87,9 +99,14 @@ Robot = function() {
 
     var request = new ROSLIB.ServiceRequest({});
     client.callService(request, function(result) {
-      callback(null, result.objects);
+      setError(result.error);
+      if (result.error) {
+        callback(null, []); // Return empty list on error.
+      } else {
+        callback(null, result.objects);
+      }
     }, function() {
-      callback(true, []);
+      callback(error ? error : 'Failed to look for objects.', []);
     });
   });
 
@@ -108,15 +125,13 @@ Robot = function() {
     client.callService(request, function(result) {
       console.log('Done navigating to ' + location + ', result:');
       console.log(result);
+      setError(result.error);
       if (result.error !== '') { // Navigation failed
         callback(null, false); // result = false
       }
       callback(null, true); // Success
     }, function(error) {
-      // Failure callback
-      console.log('GoTo service call failed.');
-      console.log(error);
-      callback(error ? error : true, null);
+      callback(error ? error : 'Failed to run navigation.', null);
     });
   });
 
@@ -134,15 +149,13 @@ Robot = function() {
     client.callService(request, function(result) {
       console.log('Done docking');
       console.log(result);
+      setError(result.error);
       if (result.error !== '') { // Docking failed
         callback(null, false); // result = false
       }
       callback(null, true); // Success
     }, function(error) {
-      // Failure callback
-      console.log('GoToDock service call failed.');
-      console.log(error);
-      callback(error ? error : true, null);
+      callback(error ? error : 'Failed to run navigation to dock.', null);
     });
   });
 
@@ -168,12 +181,14 @@ Robot = function() {
     });
 
     client.callService(request, function(result) {
-      callback(null, result.is_open);
+      setError(result.error);
+      if (result.error) {
+        callback(result.error, null); // No recovery if error with gripper service.
+      } else {
+        callback(null, result.is_open);
+      }
     }, function(error) {
-      // Failure callback
-      console.log('IsGripperOpen service call failed.');
-      console.log(error);
-      callback(error ? error : true, null);
+      callback(error ? error : 'Failed to check gripper state.', null);
     });
   });
 
@@ -199,9 +214,13 @@ Robot = function() {
     });
 
     client.callService(request, function(result) {
+      setError(result.error);
+      if (result.error) {
+        callback(result.error, null); // No recovery.
+      }
       callback(null, null);
     }, function(error) {
-      callback(error ? error : true, null);
+      callback(error ? error : 'Failed to look at target.', null);
     });
   });
 
@@ -232,9 +251,14 @@ Robot = function() {
     });
 
     client.callService(request, function(result) {
-      callback(null, true);
+      setError(result.error);
+      if (result.error) {
+        callback(null, false);
+      } else {
+        callback(null, true);
+      }
     }, function(error) {
-      callback(error ? error : true, false);
+      callback(error ? error : 'Failed to run object picking.', false);
     });
   });
 
@@ -253,9 +277,14 @@ Robot = function() {
     });
 
     client.callService(request, function(result) {
-      callback(null, true);
+      setError(result.error);
+      if (result.error) {
+        callback(null, false);
+      } else {
+        callback(null, true);
+      }
     }, function(error) {
-      callback(error ? error : true, false);
+      callback(error ? error : 'Failed to run object placing.', false);
     });
   });
 
@@ -274,9 +303,10 @@ Robot = function() {
     // Some implementations may not know when the sound has finished.
     // Keep in mind that this block may not be synchronous.
     client.callService(request, function(result) {
+      setError(result.error); // Sound not playing is probably not fatal enough to quit the program over.
       callback(null, null);
     }, function(error) {
-      callback(error ? error : true, null);
+      callback(error ? error : 'Speech failed to run.', null);
     });
   });
 
@@ -297,11 +327,14 @@ Robot = function() {
     });
 
     client.callService(request, function(result) {
-      callback(null, null);
+      setError(result.error);
+      if (result.error) {
+        callback(result.error, null); // No recovery.
+      } else {
+        callback(null, null);
+      }
     }, function(error) {
-      console.log('Error calling SetGripper');
-      console.log(error);
-      callback(error ? error : true, null);
+      callback(error ? error : 'Failed to set gripper.', null);
     });
   });
 
@@ -319,17 +352,22 @@ Robot = function() {
     });
 
     client.callService(request, function(result) {
-      callback(null, null);
+      setError(result.error);
+      if (result.error) {
+        callback(result.error, null);
+      } else {
+        callback(null, null);
+      }
     }, function(error) {
-      console.log(error);
-      callback(null, null);
+      callback(error ? error : 'Failed to tuck arms.', null);
     });
   });
 
   return {
     askMultipleChoice: askMultipleChoice,
     displayMessage: displayMessage,
     findObjects: findObjects,
+    getError: getError,
     goTo: goTo,
     goToDock: goToDock,
     isGripperOpen: isGripperOpen,
@@ -338,6 +376,7 @@ Robot = function() {
     pick: pick,
     place: place,
     say: say,
+    setError: setError,
     setGripper: setGripper,
     tuckArms: tuckArms,
   };

frontend/app/elements/code-it-blockly/code-it-blockly.html

@@ -1,4 +1,5 @@
 <link rel="import" href="../../bower_components/polymer/polymer.html">
+<link rel="import" href="../../bower_components/paper-toast/paper-toast.html">
 <link rel="import" href="blockly-import.html">
 <dom-module id="code-it-blockly">
   <template>
@@ -80,6 +81,7 @@
         </section>
       </iron-pages>
     </div>
+    <paper-toast id="toast"></paper-toast>
   </template>
   <script>
   (function() {
@@ -112,7 +114,8 @@
         isRunning: {
           type: Boolean,
           value: false,
-        }
+        },
+        _errorTopic: Object,
       },
 
       ready: function() {
@@ -125,6 +128,16 @@
         this.isRunningTopic.subscribe(function(msg) {
           that._handleIsRunningMsg(that, msg);
         });
+
+        this._errorTopic = new ROSLIB.Topic({
+          ros: ROS,
+          name: '/code_it/errors',
+          type: 'std_msgs/String'
+        });
+        this._errorTopic.subscribe(function(msg) {
+          that.$.toast.text = msg.data;
+          that.$.toast.show();
+        });
       },
 
       _handleIsRunningMsg: function(that, msg) {