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sith/composer.py

@@ -0,0 +1,26 @@
+import os
+import signal
+import subprocess
+import sys
+
+import psutil
+
+COMPOSER_PID = "COMPOSER_PID"
+
+
+def start_composer(procfile: str):
+    """Starts the composer and stores the PID as an environment variable
+    This allows for running smoothly with the django reloader
+    """
+    process = subprocess.Popen(
+        [sys.executable, "-m", "honcho", "-f", procfile, "start"],
+    )
+    os.environ[COMPOSER_PID] = str(process.pid)
+
+
+def stop_composer():
+    """Stops the composer if it was started before"""
+    if (pid := os.environ.get(COMPOSER_PID, None)) is not None:
+        process = psutil.Process(int(pid))
+        process.send_signal(signal.SIGTERM)
+        process.wait()