denis/configure: inform user when dumping dirty

denis/config.py

@@ -0,0 +1 @@
+RELOAD_FILE = '/tmp/denis_reload_file'

denis/configure.py

@@ -3,8 +3,10 @@
 from datetime import datetime
 from argparse import ArgumentParser as ap
 import sys
+import os
 
 import db
+import config
 
 #  FIXME: if you are reading this in the year 9999...
 far_future = 253401417420
@@ -133,6 +135,11 @@ def timestamp_to_formatted(timestamp):
         dt = datetime.fromtimestamp(timestamp).astimezone()
         return dt.isoformat() if fmt_iso else dt.strftime('%a %b %d %Y %T %Z (%z)')
 
+    reload_mtime = os.path.getmtime(config.RELOAD_FILE)
+    db_mtime = os.path.getmtime(db.DB_PATH)
+    if (db_mtime > reload_mtime):
+        print('WARNING: Denis database is dirty, reload to update waiters')
+
     print(' --- Assignments ---')
     for asn in db.Assignment.select():
         print(f'''{asn.name}:
@@ -146,6 +153,8 @@ def reload():
     import signal
     try:
         os.kill(1, signal.SIGUSR1)
+        # update mtime/utime with last reload
+        os.utime(config.RELOAD_FILE)
     except OSError as e:
         errx(f'kill: {e}')
 

denis/db.py

@@ -1,7 +1,8 @@
 #!/usr/bin/env python3
 import peewee
 
-DB = peewee.SqliteDatabase("/var/lib/denis/assignments.db")
+DB_PATH = '/var/lib/denis/assignments.db'
+DB = peewee.SqliteDatabase(DB_PATH)
 
 
 class BaseModel(peewee.Model):

denis/start.py

@@ -6,6 +6,7 @@
 import sys
 
 import db
+import config
 
 from configure import far_future
 
@@ -62,6 +63,9 @@ def signal_handler(*_):
     signal.signal(signal.SIGUSR1, signal_handler)
     signal.signal(signal.SIGRTMIN, signal_handler)
 
+    # create reload file
+    open(config.RELOAD_FILE, 'w').close()
+
     again = True
     while again:
         procs = []