From ba9cedf62125bfd46ad45bf73b23f60b97ce2cb2 Mon Sep 17 00:00:00 2001
From: Chris Lalancette <clalancette@gmail.com>
Date: Wed, 17 May 2023 13:27:00 +0000
Subject: [PATCH] Switch to meaningful names for the event_type.

Signed-off-by: Chris Lalancette <clalancette@gmail.com>
---
 ros2service/ros2service/verb/echo.py | 40 +++++++++++++++++++++++-----
 ros2service/test/test_echo.py        |  8 +++---
 2 files changed, 38 insertions(+), 10 deletions(-)

diff --git a/ros2service/ros2service/verb/echo.py b/ros2service/ros2service/verb/echo.py
index be801ec35..e484bd7a8 100644
--- a/ros2service/ros2service/verb/echo.py
+++ b/ros2service/ros2service/verb/echo.py
@@ -12,6 +12,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+from collections import OrderedDict
+import sys
 from typing import TypeVar
 
 import rclpy
@@ -24,10 +26,13 @@
 from ros2service.api import ServiceTypeCompleter
 from ros2service.verb import VerbExtension
 from rosidl_runtime_py import message_to_csv
-from rosidl_runtime_py import message_to_yaml
+from rosidl_runtime_py import message_to_ordereddict
 from rosidl_runtime_py.utilities import get_service
 from service_msgs.msg import ServiceEventInfo
 
+import yaml
+
+
 DEFAULT_TRUNCATE_LENGTH = 128
 MsgType = TypeVar('MsgType')
 
@@ -35,9 +40,20 @@
 class EchoVerb(VerbExtension):
     """Echo a service."""
 
+    # Custom representer for getting clean YAML output that preserves the order in an OrderedDict.
+    # Inspired by: http://stackoverflow.com/a/16782282/7169408
+    def __represent_ordereddict(self, dumper, data):
+        items = []
+        for k, v in data.items():
+            items.append((dumper.represent_data(k), dumper.represent_data(v)))
+        return yaml.nodes.MappingNode(u'tag:yaml.org,2002:map', items)
+
     def __init__(self):
-        self.event_type_map = [
-            (v, k) for k, v in ServiceEventInfo._Metaclass_ServiceEventInfo__constants.items()]
+        self._event_number_to_name = {}
+        for k, v in ServiceEventInfo._Metaclass_ServiceEventInfo__constants.items():
+            self._event_number_to_name[v] = k
+
+        yaml.add_representer(OrderedDict, self.__represent_ordereddict)
 
     def add_arguments(self, parser, cli_name):
         arg = parser.add_argument(
@@ -126,9 +142,21 @@ def _subscriber_callback(self, msg):
             to_print = message_to_csv(msg, truncate_length=self.truncate_length,
                                       no_arr=self.no_arr, no_str=self.no_str)
         else:
-            to_print = message_to_yaml(msg, truncate_length=self.truncate_length,
-                                       no_arr=self.no_arr, no_str=self.no_str,
-                                       flow_style=self.flow_style)
+            # The "easy" way to print out a representation here is to call message_to_yaml().
+            # However, the message contains numbers for the event type, but we want to show
+            # meaningful names to the user.  So we call message_to_ordereddict() instead,
+            # and replace the numbers with meaningful names before dumping to YAML.
+            msgdict = message_to_ordereddict(msg, truncate_length=self.truncate_length,
+                                             no_arr=self.no_arr, no_str=self.no_str)
+
+            if 'info' in msgdict:
+                info = msgdict['info']
+                if 'event_type' in info:
+                    info['event_type'] = self._event_number_to_name[info['event_type']]
+
+            to_print = yaml.dump(msgdict, allow_unicode=True, width=sys.maxsize,
+                                 default_flow_style=self.flow_style)
+
             to_print += '---'
 
         print(to_print)
diff --git a/ros2service/test/test_echo.py b/ros2service/test/test_echo.py
index f81aba4e8..4fca43740 100644
--- a/ros2service/test/test_echo.py
+++ b/ros2service/test/test_echo.py
@@ -115,7 +115,7 @@ def test_echo_no_arr(self):
         echo_arguments = ['echo', '/test_introspectable', '--no-arr']
         expected_output = [
             'info:',
-            '  event_type: 0',
+            '  event_type: REQUEST_SENT',
             '  stamp:',
             re.compile(r'    sec: \d+'),
             re.compile(r'    nanosec: \d+'),
@@ -125,7 +125,7 @@ def test_echo_no_arr(self):
             "response: '<sequence type: test_msgs/srv/BasicTypes_Response[1], length: 0>'",
             '---',
             'info:',
-            '  event_type: 1',
+            '  event_type: REQUEST_RECEIVED',
             '  stamp:',
             re.compile(r'    sec: \d+'),
             re.compile(r'    nanosec: \d+'),
@@ -135,7 +135,7 @@ def test_echo_no_arr(self):
             "response: '<sequence type: test_msgs/srv/BasicTypes_Response[1], length: 0>'",
             '---',
             'info:',
-            '  event_type: 2',
+            '  event_type: RESPONSE_SENT',
             '  stamp:',
             re.compile(r'    sec: \d+'),
             re.compile(r'    nanosec: \d+'),
@@ -145,7 +145,7 @@ def test_echo_no_arr(self):
             "response: '<sequence type: test_msgs/srv/BasicTypes_Response[1], length: 1>'",
             '---',
             'info:',
-            '  event_type: 3',
+            '  event_type: RESPONSE_RECEIVED',
             '  stamp:',
             re.compile(r'    sec: \d+'),
             re.compile(r'    nanosec: \d+'),