Implement delayed termination of the client on SIGINT (e.g. ctrl-c)

Fixes #5

tune/db_workers/tuning_client.py

@@ -3,6 +3,7 @@
 import logging
 import os
 import re
+import signal
 import subprocess
 import sys
 import numpy as np
@@ -21,6 +22,8 @@ def __init__(self, dbconfig_path, **kwargs):
         self.logger = logging.getLogger("TuningClient")
         self.lc0_benchmark = None
         self.sf_benchmark = None
+        signal.signal(signal.SIGINT, self.interrupt_handler)
+        self.interrupt_pressed = False
         if os.path.isfile(dbconfig_path):
             with open(dbconfig_path, "r") as config_file:
                 config = config_file.read().replace("\n", "")
@@ -29,6 +32,15 @@ def __init__(self, dbconfig_path, **kwargs):
         else:
             raise ValueError("No config file found at provided path")
 
+    def interrupt_handler(self, sig, frame):
+        if self.interrupt_pressed:
+            self.logger.info("Shutting down immediately.")
+            sys.exit(0)
+        self.interrupt_pressed = True
+        self.logger.info(
+            "Signal received. Shutting down after next match.\nPress a second time to terminate immediately."
+        )
+
     def run_experiment(self, time_control, cutechess_options):
         try:
             os.remove("out.pgn")
@@ -152,8 +164,10 @@ def pick_job(self, jobs, mix=0.25):
 
     def run(self):
         while True:
+            if self.interrupt_pressed:
+                self.logger.info('Shutting down after receiving shutdown signal.')
+                sys.exit(0)
             # 1. Check db for new job
-
             with psycopg2.connect(**self.connect_params) as conn:
                 with conn.cursor(cursor_factory=DictCursor) as curs:
                     job_string = """

tune/db_workers/tuning_server.py

@@ -1,15 +1,4 @@
-"""The server worker, which reads results and schedules new jobs.
-
-Usage:
-  tuning_server.py (run | deactivate | reactivate) [options] <experiment_file> <dbconfig>
-  tuning_server.py -h | --help
-
-Options:
-  -h --help         Show this screen.
-  -v --verbose      Set log level to debug.
-  --logfile=<path>  Path to where the log is output to
-
-"""
+"""The server worker, which reads results and schedules new jobs."""
 import joblib
 import json
 import logging