feat(multiprocess): restart child processes if they are not alive

faststream/cli/supervisors/multiprocess.py

@@ -1,3 +1,4 @@
+import signal
 from typing import TYPE_CHECKING, Any, List, Tuple
 
 from faststream.cli.supervisors.basereload import BaseReload
@@ -17,8 +18,9 @@ def __init__(
         target: "DecoratedCallable",
         args: Tuple[Any, ...],
         workers: int,
+        reload_delay: float = 0.5,
     ) -> None:
-        super().__init__(target, args, None)
+        super().__init__(target, args, reload_delay)
 
         self.workers = workers
         self.processes: List[SpawnProcess] = []
@@ -38,3 +40,30 @@ def shutdown(self) -> None:
             process.join()
 
         logger.info(f"Stopping parent process [{self.pid}]")
+
+    def restart(self) -> None:
+        active_processes = []
+
+        for process in self.processes:
+            if process.is_alive():
+                active_processes.append(process)
+                continue
+
+            pid = process.pid
+            exitcode = process.exitcode
+
+            log_msg = "Worker (pid:%s) exited with code %s."
+            if exitcode and abs(exitcode) == signal.SIGKILL:
+                log_msg += " Perhaps out of memory?"
+            logger.error(log_msg, pid, exitcode)
+
+            process.kill()
+
+            new_process = self._start_process()
+            logger.info(f"Started child process [{new_process.pid}]")
+            active_processes.append(new_process)
+
+        self.processes = active_processes
+
+    def should_restart(self) -> bool:
+        return not all(p.is_alive() for p in self.processes)