From 94d0fda6ab82dad3ec474f8fededde13426a902c Mon Sep 17 00:00:00 2001
From: Klaas van Schelven <klaas@vanschelven.com>
Date: Fri, 19 Apr 2024 11:58:20 +0200
Subject: [PATCH] Midway checking to preserve state

---
 snappea/__init__.py                        |  0
 snappea/admin.py                           |  3 +
 snappea/apps.py                            |  6 ++
 snappea/foreman.py                         | 68 ++++++++++++++++++++++
 snappea/management/__init__.py             |  0
 snappea/management/commands/__init__.py    |  0
 snappea/management/commands/run_snappea.py | 11 ++++
 snappea/migrations/__init__.py             |  0
 snappea/models.py                          |  3 +
 snappea/tests.py                           |  3 +
 snappea/views.py                           |  3 +
 11 files changed, 97 insertions(+)
 create mode 100644 snappea/__init__.py
 create mode 100644 snappea/admin.py
 create mode 100644 snappea/apps.py
 create mode 100644 snappea/foreman.py
 create mode 100644 snappea/management/__init__.py
 create mode 100644 snappea/management/commands/__init__.py
 create mode 100644 snappea/management/commands/run_snappea.py
 create mode 100644 snappea/migrations/__init__.py
 create mode 100644 snappea/models.py
 create mode 100644 snappea/tests.py
 create mode 100644 snappea/views.py

diff --git a/snappea/__init__.py b/snappea/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/snappea/admin.py b/snappea/admin.py
new file mode 100644
index 0000000..8c38f3f
--- /dev/null
+++ b/snappea/admin.py
@@ -0,0 +1,3 @@
+from django.contrib import admin
+
+# Register your models here.
diff --git a/snappea/apps.py b/snappea/apps.py
new file mode 100644
index 0000000..dcd6476
--- /dev/null
+++ b/snappea/apps.py
@@ -0,0 +1,6 @@
+from django.apps import AppConfig
+
+
+class SnappeaConfig(AppConfig):
+    default_auto_field = 'django.db.models.BigAutoField'
+    name = 'snappea'
diff --git a/snappea/foreman.py b/snappea/foreman.py
new file mode 100644
index 0000000..387764b
--- /dev/null
+++ b/snappea/foreman.py
@@ -0,0 +1,68 @@
+import os
+import logging
+import time
+import signal
+import threading
+from sentry_sdk import capture_exception
+
+
+logger = logging.getLogger("snappea.foreman")
+
+
+def example_worker():
+    logger.info("example worker started")
+    time.sleep(10)
+    logger.info("example worker stopped")
+
+
+def example_failing_worker():
+    raise Exception("I am failing")
+
+
+lll = []
+
+
+class Foreman:
+
+    def __init__(self):
+        # signal.signal(signal.SIGTERM, self.handle_sigterm)  later
+        signal.signal(signal.SIGUSR1, self.handle_sigusr1)
+
+        self.workers = []
+
+        pid = os.getpid()
+        logger.info("Foreman created, my pid is %s", pid)
+        with open("/tmp/snappea.pid", "w") as f:
+            f.write(str(pid))
+
+    def handle_sigterm(self, sig, frame):
+        print("Handling SIGTERM signal")
+
+    def run_in_thread(self, function, *args, **kwargs):
+        def non_failing_function(*inner_args, **inner_kwargs):
+            try:
+                function(*inner_args, **inner_kwargs)
+            except Exception as e:
+                # Potential TODO: make this configurable / depend on our existing config in bugsink/settings.py
+                logger.info("Worker exception: %s", str(e))
+                capture_exception(e)
+
+        worker_thread = threading.Thread(target=non_failing_function, *args, **kwargs)
+        worker_thread.run()
+        return worker_thread
+
+    def handle_sigusr1(self, sig, frame):
+        logger.info("Received signal, starting new thread")
+        self.run_in_thread(example_failing_worker)
+        # worker_thread = threading.Thread(target=example_worker)
+
+        lll.append("x")
+        me = len(lll)
+        for i in range(4):
+            print("am I locked?", me, i)
+            time.sleep(1)
+
+    def run_forever(self):
+        # there is no actual code here, all the action happens in the signal handlers
+        while True:
+            time.sleep(3600)
diff --git a/snappea/management/__init__.py b/snappea/management/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/snappea/management/commands/__init__.py b/snappea/management/commands/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/snappea/management/commands/run_snappea.py b/snappea/management/commands/run_snappea.py
new file mode 100644
index 0000000..0437b39
--- /dev/null
+++ b/snappea/management/commands/run_snappea.py
@@ -0,0 +1,11 @@
+from django.core.management.base import BaseCommand
+
+from snappea.foreman import Foreman
+
+
+class Command(BaseCommand):
+    help = "Run the SnapPea foreman service."
+
+    def handle(self, *args, **options):
+
+        Foreman().run_forever()
diff --git a/snappea/migrations/__init__.py b/snappea/migrations/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/snappea/models.py b/snappea/models.py
new file mode 100644
index 0000000..71a8362
--- /dev/null
+++ b/snappea/models.py
@@ -0,0 +1,3 @@
+from django.db import models
+
+# Create your models here.
diff --git a/snappea/tests.py b/snappea/tests.py
new file mode 100644
index 0000000..7ce503c
--- /dev/null
+++ b/snappea/tests.py
@@ -0,0 +1,3 @@
+from django.test import TestCase
+
+# Create your tests here.
diff --git a/snappea/views.py b/snappea/views.py
new file mode 100644
index 0000000..91ea44a
--- /dev/null
+++ b/snappea/views.py
@@ -0,0 +1,3 @@
+from django.shortcuts import render
+
+# Create your views here.