Add --delay command line and delay config options

Make the alert and forecast expiration delay user-configurable, both
in configuration and at runtime on the command line.

weather

@@ -2,7 +2,7 @@
 # distributions may wish to edit the above to refer to a specific interpreter
 # path, such as #!/usr/bin/python
 
-# Copyright (c) 2006-2012 Jeremy Stanley <fungi@yuggoth.org>. Permission to
+# Copyright (c) 2006-2024 Jeremy Stanley <fungi@yuggoth.org>. Permission to
 # use, copy, modify, and distribute this software is granted under terms
 # provided in the LICENSE file distributed with this software.
 
@@ -101,7 +101,8 @@ else:
                             and selections.get_bool("cache_data")
                     ),
                     cacheage=selections.getint("cacheage"),
-                    cachedir=selections.get("cachedir")
+                    cachedir=selections.get("cachedir"),
+                    delay=selections.getint("delay")
                 )
                 if partial:
                     alert_text += "***** %s *****\n%s\n" % (

weather.py

@@ -320,7 +320,8 @@ def get_alert(
     quiet=False,
     cache_data=False,
     cacheage=900,
-    cachedir="."
+    cachedir=".",
+    delay=1
 ):
     """Return alert notice for the specified URI."""
     if not uri:
@@ -343,14 +344,13 @@ def get_alert(
                 muted = False
             expirycheck = re.search(r"Expires:([0-9]{12})", alert)
             if expirycheck:
-                # only report alerts and forecasts that expired less than
-                # offset ago
+                # only report alerts and forecasts that expired less than delay
+                # hours ago
                 import datetime, zoneinfo
                 expiration = datetime.datetime.fromisoformat(
                     "%sT%sZ" % (expirycheck[1][:8], expirycheck[1][-4:]))
                 now = datetime.datetime.now(tz=zoneinfo.ZoneInfo("UTC"))
-                # TODO: make this offset configurable
-                if now - expiration > datetime.timedelta(hours=1):
+                if now - expiration > datetime.timedelta(hours=delay):
                     return ""
             lines = alert.split("\n")
             output = []
@@ -437,6 +437,15 @@ def get_options(config):
         default=default_cachedir,
         help="directory for storing cached searches and data")
 
+    # the --delay option
+    if config.has_option("default", "delay"):
+        default_delay = config.getint("default", "delay")
+    else: default_delay = 1
+    option_parser.add_option("--delay",
+        dest="delay",
+        default=default_delay,
+        help="hours to delay alert and forecast expiration")
+
     # the -f/--forecast option
     if config.has_option("default", "forecast"):
         default_forecast = config.getboolean("default", "forecast")