From bac4e01f40ae7bd19d1eab1fb9349452c18de8f5 Mon Sep 17 00:00:00 2001
From: Simon Willison <swillison@gmail.com>
Date: Sun, 21 Apr 2019 12:02:24 -0700
Subject: [PATCH] Ensure sqlite_timelimit correctly clears handler

If an error occurred inside the block the progress handler (used to
enforce a time limit) was not being correctly cleared, resulting in
timeout errors potentially occurring during subsequent SQL queries.

The fix is described here: https://docs.python.org/3/library/contextlib.html#contextlib.contextmanager
---
 datasette/utils.py | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/datasette/utils.py b/datasette/utils.py
index 0c161ac6..7ebf4f23 100644
--- a/datasette/utils.py
+++ b/datasette/utils.py
@@ -152,8 +152,10 @@ def sqlite_timelimit(conn, ms):
             return 1
 
     conn.set_progress_handler(handler, n)
-    yield
-    conn.set_progress_handler(None, n)
+    try:
+        yield
+    finally:
+        conn.set_progress_handler(None, n)
 
 
 class InvalidSql(Exception):