Allow memcacheexpire to be a callable

.pre-commit-config.yaml

@@ -2,7 +2,7 @@ ci:
   autoupdate_schedule: quarterly
 repos:
   - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: "v0.5.3"
+    rev: "v0.5.4"
     hooks:
       - id: ruff
         args: [--fix, --exit-non-zero-on-fix]

CHANGELOG.md

@@ -13,6 +13,7 @@ All notable changes to this library are documented in this file.
 ### New Features
 
 - Add `_check_dueling_tropics` VTEC check looking for TR+HU overlap (#930).
+- Allow `iemapp(memcachexpire)` to be a callable, called back with environ.
 - Cross check WCNs against watch database storage for PDS status (#925).
 - For `iemapp` if the `memcachekey=` callable returns `None`, the check of
 memcache is short circuited.

src/pyiem/webutil.py

@@ -361,7 +361,9 @@ def _mcall(func, environ, start_response, memcachekey, expire, content_type):
     res = mc.get(key)
     if not res:
         res = func(environ, start_response)
-        mc.set(key, res, expire)
+        mc.set(
+            key, res, expire if isinstance(expire, int) else expire(environ)
+        )
     else:
         # since our function never got called, we need to start_response
         ct = (
@@ -396,7 +398,8 @@ def iemapp(**kwargs):
         - schema (BaseModel): A Pydantic model to parse the form with.
         - memcachekey (str or callable): A memcache key to use for caching
           the response. If the callable returns `None`, no caching is done.
-        - memcacheexpire (int): The number of seconds to cache the response.
+        - memcacheexpire (int or callable): The number of seconds to cache
+          the response, defaults to 3600.
         - content_type (str or callable): The content type to use for the
           response.
 

tests/test_webutil.py

@@ -29,7 +29,7 @@
 def test_memcachekey_is_none():
     """Test that we can handle a None memcachekey."""
 
-    @iemapp(memcachekey=lambda _e: None)
+    @iemapp(memcachekey=lambda _e: None, memcacheexpire=lambda _e: 60)
     def application(_environ, _start_response):
         """Test."""
         return f"aa{random.random()}".encode("ascii")

tests/test_windrose_utils.py

@@ -173,11 +173,11 @@ def test_windrose_hads_wind():
     """Test the database filtering with actual database data."""
     # Faked from iem-database repo store_test_data
     fig = windrose(
-        "XXXX",
+        "EOKI4",
         database="hads",
         months=[4, 5, 6],
-        sts=utc(2020, 1, 5),
-        ets=utc(2020, 9, 5),
+        sts=utc(2024, 1, 5),
+        ets=utc(2024, 9, 5),
         tzname="America/Chicago",
         nogenerated=True,
     )