Update the basic plugins for ROS2 (#72)

* Update the basic plugins for ROS2

Update message_view, raw_view, and topic_message_view with
changes required to port to ROS.

Signed-off-by: Michael Jeronimo <[email protected]>

* Revert to utf_8_decode, adding decode() which was missing previously

Signed-off-by: Michael Jeronimo <[email protected]>

* Clarify the reason for stripping the leading underscore

Signed-off-by: Michael Jeronimo <[email protected]>

* Per code review, use keyword args for the base class message_viewed method and overrides

Signed-off-by: Michael Jeronimo <[email protected]>

rqt_bag/src/rqt_bag/plugins/message_view.py

@@ -33,6 +33,8 @@
 
 from python_qt_binding.QtCore import QObject
 
+import rosbag2_py
+
 
 class MessageView(QObject):
 
@@ -47,19 +49,20 @@ def __init__(self, timeline, topic):
         self.timeline = timeline
         self.topic = topic
 
-    def message_viewed(self, bag, msg_details):
+    def message_viewed(self, *, bag, entry, ros_message, msg_type_name, topic):
         """
         View the message.
 
         @param bag: the bag file the message is contained in
         @type  bag: rosbag.Bag
-        @param msg_details: the details of the message to be viewed
-        @type msg_details: tuple (topic, msg, time)
-            @param topic: the message topic
-            @type  topic: str
-            @param msg: the message
-            @param t: the message timestamp
-            @type  t: rospy.Time
+        @param entry: the bag entry of the message to be viewed
+        @type entry: tuple (id, topic_id, timestamp, data)
+        @param ros_message: the (deserialized) ROS message
+        @type msg: ROS message
+        @param msg_type_name: the name of the message type
+        @type string
+        @param topic: the topic on which the message was recorded
+        @type topic: string
         """
         pass
 
@@ -88,9 +91,10 @@ def event(self, event):
         This function will be called to process events posted by post_event
         it will call message_cleared or message_viewed with the relevant data
         """
-        bag, msg_data = event.data
-        if msg_data:
-            self.message_viewed(bag, msg_data)
+        bag, entry = event.data
+        if entry:
+            (ros_message, msg_type_name, topic) = bag.convert_entry_to_ros_message(entry)
+            self.message_viewed(bag=bag, entry=entry, ros_message=ros_message, msg_type_name=msg_type_name, topic=topic)
         else:
             self.message_cleared()
         return True

rqt_bag/src/rqt_bag/plugins/raw_view.py

@@ -66,17 +66,16 @@ def __init__(self, timeline, parent, topic):
         # This will automatically resize the message_tree to the windowsize
         parent.layout().addWidget(self.message_tree)
 
-    def message_viewed(self, bag, msg_details):
-        super(RawView, self).message_viewed(bag, msg_details)
-        _, _, _, msg = msg_details  # id, topic, timestamp, msg = msg_details
-        if msg is None:
+    def message_viewed(self, *, entry, ros_message, msg_type_name, **kwargs):
+        super(RawView, self).message_viewed(entry=entry, ros_message=ros_message, msg_type_name=msg_type_name)
+        if ros_message is None:
             self.message_cleared()
         else:
-            self.message_tree.set_message(msg)
+            self.message_tree.set_message(ros_message, msg_type_name)
 
     def message_cleared(self):
         TopicMessageView.message_cleared(self)
-        self.message_tree.set_message(None)
+        self.message_tree.set_message(None, None)
 
 
 class MessageTree(QTreeWidget):
@@ -96,7 +95,7 @@ def __init__(self, parent):
     def msg(self):
         return self._msg
 
-    def set_message(self, msg):
+    def set_message(self, msg, msg_type_name):
         """
         Clears the tree view and displays the new message
         :param msg: message object to display in the treeview, ''msg''
@@ -111,12 +110,12 @@ def set_message(self, msg):
                     self._expanded_paths.remove(path)
             self.clear()
         if msg:
-            self.setHeaderLabel(msg._type)
+            self.setHeaderLabel(msg_type_name)
 
             # Populate the tree
             # TODO(brawner) msg is stored in the db as a serialized byte array, needs to be
             # unserialized
-            # self._add_msg_object(None, '', '', msg, msg._type)
+            self._add_msg_object(None, '', '', msg, msg_type_name)
 
             if self._expanded_paths is None:
                 self._expanded_paths = set()
@@ -209,7 +208,7 @@ def _add_msg_object(self, parent, path, name, obj, obj_type):
 
         elif type(obj) in [str, bool, int, long, float, complex, Time]:
             # Ignore any binary data
-            obj_repr = codecs.utf_8_decode(str(obj), 'ignore')[0]
+            obj_repr = codecs.utf_8_decode(str(obj).decode(), 'ignore')[0]
 
             # Truncate long representations
             if len(obj_repr) >= 50:
@@ -229,6 +228,12 @@ def _add_msg_object(self, parent, path, name, obj, obj_type):
             if subobj is None:
                 continue
 
+            # Strip the leading underscore for display. In ROS2, the Python IDL generator
+            # adds a leading underscore for each name in __slots__, whereas the name of
+            # the field does not have a leading underscore.
+            if hasattr(obj, '__slots__') and subobj_name[0] == '_':
+                subobj_name = subobj_name[1:]
+
             if path == '':
                 subpath = subobj_name  # root field
             elif subobj_name.startswith('['):

rqt_bag/src/rqt_bag/plugins/topic_message_view.py

@@ -74,8 +74,8 @@ def stamp(self):
 
     # MessageView implementation
 
-    def message_viewed(self, bag, msg_details):
-        _, _, self._stamp = msg_details[:3]
+    def message_viewed(self, *, entry, **kwargs):
+        self._stamp = entry.timestamp
 
     # Events
     def navigate_first(self):