From 00bcefcccaca1a3ebc2ee5410993ca02507b5270 Mon Sep 17 00:00:00 2001
From: Benedikt Ziemons <benedikt.ziemons@athox.de>
Date: Wed, 2 Dec 2020 11:15:56 +0100
Subject: [PATCH] Allow sending USR signals to pod

---
 .idea/misc.xml |  2 +-
 main.py        | 28 ++++++++++++++++++++++------
 2 files changed, 23 insertions(+), 7 deletions(-)

diff --git a/.idea/misc.xml b/.idea/misc.xml
index 479ee61..608768e 100644
--- a/.idea/misc.xml
+++ b/.idea/misc.xml
@@ -1,4 +1,4 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
-  <component name="ProjectRootManager" version="2" project-jdk-name="Python 3.8 (.venv)" project-jdk-type="Python SDK" />
+  <component name="ProjectRootManager" version="2" project-jdk-name="Python 3.9 (podlaunch)" project-jdk-type="Python SDK" />
 </project>
\ No newline at end of file
diff --git a/main.py b/main.py
index 9f4bf93..385643e 100644
--- a/main.py
+++ b/main.py
@@ -5,7 +5,8 @@ import sys
 import threading
 import traceback
 from datetime import datetime
-from signal import signal, SIGHUP, SIGINT, SIGTERM, setitimer, SIGALRM, ITIMER_REAL
+from queue import SimpleQueue
+from signal import signal, SIGHUP, SIGINT, SIGTERM, setitimer, SIGALRM, ITIMER_REAL, SIGUSR1, SIGUSR2, strsignal
 
 import click
 import sh
@@ -37,6 +38,8 @@ class PodKeeper:
         self.checking = threading.Event()
         self.waiter = threading.Event()
         self.last_check = datetime.utcnow()
+        self.passing_signal = threading.Event()
+        self.pass_signal_nums = SimpleQueue()
 
     def destroy(self, signum, stackframe):
         print("Destroy signal", signum, file=sys.stderr, flush=True)
@@ -52,6 +55,11 @@ class PodKeeper:
         self.checking.set()
         self.waiter.set()
 
+    def passthrough(self, signum, stackframe):
+        self.pass_signal_nums.put(item=signum, block=True, timeout=3)
+        self.passing_signal.set()
+        self.waiter.set()
+
     def run(self):
         os.chdir(self.podhome)
         if self.stop_previous and podman.pod.exists(self.podname, _ok_code=[0, 1]).exit_code == 0:
@@ -68,25 +76,31 @@ class PodKeeper:
                 self.waiter.wait()
                 self.waiter.clear()
 
+                if self.passing_signal.is_set():
+                    self.passing_signal.clear()
+                    while not self.pass_signal_nums.empty():
+                        signum = self.pass_signal_nums.get(block=True, timeout=2)
+                        self.signal_pod(signum)
+
                 if self.checking.is_set():
                     self.checking.clear()
                     self.check_pod()
 
                 if self.reloading.is_set():
                     self.reloading.clear()
-                    self.reload_pod()
+                    self.signal_pod(SIGHUP)
 
             if 'NOTIFY_SOCKET' in os.environ:
                 sdnotify("--status=Stopping pod")
         finally:
             self.stop_pod()
 
-    def reload_pod(self):
-        print("Reloading pod", self.podname, file=sys.stderr, flush=True)
+    def signal_pod(self, signum):
+        print(f"Sending signal '{strsignal(signum)}' to pod {self.podname}", file=sys.stderr, flush=True)
         try:
-            podman.pod.kill("--signal", "HUP", self.podname)
+            podman.pod.kill("--signal", str(signum), self.podname)
         except sh.ErrorReturnCode:
-            print("Error reloading pod", file=sys.stderr, flush=True)
+            print("Error signaling pod", file=sys.stderr, flush=True)
             traceback.print_exc()
 
     def check_pod(self):
@@ -131,6 +145,8 @@ def main(network, stop_previous, identifier):
     signal(SIGTERM, keeper.destroy)
     signal(SIGHUP, keeper.reload)
     signal(SIGALRM, keeper.check)
+    signal(SIGUSR1, keeper.passthrough)
+    signal(SIGUSR2, keeper.passthrough)
     setitimer(ITIMER_REAL, 4.0, 10.0)
 
     keeper.run()