Added zenoh router start for basic_service_client_benchmark

launch/scenario_basic_service_client_benchmark.launch.py

@@ -1,7 +1,7 @@
 import os
 from launch import LaunchDescription
 from launch.substitutions import LaunchConfiguration
-from ament_index_python.packages import get_package_share_directory
+from ament_index_python.packages import get_package_share_directory, get_package_prefix
 from launch.actions import (
     DeclareLaunchArgument,
     ExecuteProcess,
@@ -10,6 +10,66 @@
 )
 from launch_ros.substitutions import FindPackageShare
 from launch_ros.actions import Node
+import subprocess
+
+"""
+Zenoh router needs to use /dev/tty as stdin. We cannot set stdin in ExecuteProcess.
+The functionality of launch tool doesn't allow to set stdin, Even if we use
+shell=True parameter and set stdin using ros2 run rmw_zenoh_cpp rmw_zenoh < /dev/tty,
+launch closes process unsoundly, it somehow trigger neither the SIGTERM nor SIGINT.
+I could solve this using separate subprocess mechanism, which allows us to modify stdin of process directly.
+See my comment in this issue. ( https://github.com/ros2/rmw_zenoh/issues/206#issuecomment-2257292941 )
+
+TODO: (CihatAltiparmak) Remove this class when rmw_zenoh becomes runnable without starting router
+separately or when tty option is removed from router executable
+"""
+
+
+class ZenohRouterStarter:
+    def __init__(self):
+        self.tty_file_descriptor = None
+        self.zenoh_router_sub_process = None
+
+    def start_router(self):
+        try:
+            rmw_zenoh_cpp_router_executable_path = os.path.join(
+                get_package_prefix("rmw_zenoh_cpp"), "lib/rmw_zenoh_cpp/rmw_zenohd"
+            )
+
+            self.tty_file_descriptor = open("/dev/tty")
+            self.zenoh_router_sub_process = subprocess.Popen(
+                [rmw_zenoh_cpp_router_executable_path],
+                stdin=self.tty_file_descriptor,
+            )
+        except Exception as err:
+            print(f"Unexpected {err=}, {type(err)=}")
+            raise
+
+    def terminate_router(self):
+        self.zenoh_router_sub_process.terminate()
+        self.zenoh_router_sub_process.wait()
+
+    def __del__(self):
+        if self.tty_file_descriptor is not None:
+            self.tty_file_descriptor.close()
+
+
+# for rmw_zenoh_router
+zenoh_router_starter = ZenohRouterStarter()
+if (
+    "RMW_IMPLEMENTATION" in os.environ.keys()
+    and os.environ.get("RMW_IMPLEMENTATION") == "rmw_zenoh_cpp"
+):
+    zenoh_router_starter.start_router()
+
+
+def shutdown_launch():
+    if (
+        "RMW_IMPLEMENTATION" in os.environ.keys()
+        and os.environ.get("RMW_IMPLEMENTATION") == "rmw_zenoh_cpp"
+    ):
+        zenoh_router_starter.terminate_router()
+    Shutdown()()
 
 
 def launch_setup(context, *args, **kwargs):
@@ -36,7 +96,7 @@ def launch_setup(context, *args, **kwargs):
         parameters=[
             {"sending_request_number": sending_request_number},
         ],
-        on_exit=Shutdown(),
+        on_exit=lambda *args: shutdown_launch(),
     )
 
     return [add_two_ints_server_node, benchmark_main_node]