Add __repr__ to GroupMod (+4 classes)

Implement a useful repr() in: GroupMod, Header,
Bucket, ActionSetField and ActionOutput.
Fix #635.

Author: hdiogenes

pyof/v0x04/common/action.py

@@ -328,6 +328,9 @@ def __init__(self, port=None,
         self.port = port
         self.max_length = max_length
 
+    def __repr__(self):
+        return f"{type(self).__name__}(port={self.port})"
+
 
 class ActionPopMPLS(ActionHeader):
     """Action structure for OFPAT_POP_MPLS."""
@@ -388,6 +391,10 @@ def __init__(self, field=None):
         super().__init__(action_type=ActionType.OFPAT_SET_FIELD)
         self.field = OxmTLV() if field is None else field
 
+    def __repr__(self):
+        return (f"{type(self).__name__}({self.field.oxm_field!s}, "
+                f"{self.field.oxm_value})")
+
     def pack(self, value=None):
         """Pack this structure updating the length and padding it."""
         self._update_length()

pyof/v0x04/common/header.py

@@ -102,3 +102,7 @@ def __init__(self, message_type=None, length=None, xid=None):
         self.message_type = message_type
         self.length = length
         self.xid = xid
+
+    def __repr__(self):
+        return (f"{type(self).__name__}(version={self.version}, "
+                f"xid={self.xid}, {self.message_type!s})")

pyof/v0x04/controller2switch/common.py

@@ -224,6 +224,9 @@ def __init__(self, length=None, weight=None, watch_port=None,
         self.watch_group = watch_group
         self.actions = actions
 
+    def __repr__(self):
+        return f"{type(self).__name__}(actions={self.actions!r})"
+
     def unpack(self, buff, offset=0):
         """Unpack bucket.
 

pyof/v0x04/controller2switch/group_mod.py

@@ -91,3 +91,8 @@ def __init__(self, xid=None, command=None, group_type=None, group_id=None,
         self.group_type = group_type
         self.group_id = group_id
         self.buckets = buckets
+
+    def __repr__(self):
+        return (f"{type(self).__name__}(xid={self.header.xid}, {self.command},"
+                f" group_type={self.group_type}, group_id={self.group_id},"
+                f" buckets={self.buckets!r})")