From 1c9c2daf83546619f36c7309d46a44fce2806848 Mon Sep 17 00:00:00 2001
From: Matt Westcott <matt@west.co.tt>
Date: Wed, 12 Jan 2022 11:57:03 +0000
Subject: [PATCH] Warn and use fallback backend if fts5 is available but the
index table is missing
This scenario will happen if sqlite has been upgraded to a version with fts5 support since wagtailsearch migration 0006 was run.
---
wagtail/search/backends/database/__init__.py | 25 +++++++++++++++++--
.../search/backends/database/sqlite/utils.py | 13 ++++++++++
2 files changed, 36 insertions(+), 2 deletions(-)
diff --git a/wagtail/search/backends/database/__init__.py b/wagtail/search/backends/database/__init__.py
index 6e181b2b31..255eda268b 100644
--- a/wagtail/search/backends/database/__init__.py
+++ b/wagtail/search/backends/database/__init__.py
@@ -1,6 +1,11 @@
+import warnings
+
from django.db import connection
+USE_SQLITE_FTS = None # True if sqlite FTS is available, False if not, None if untested
+
+
def SearchBackend(params):
"""
Returns the appropriate search backend for the current 'default' database system
@@ -12,8 +17,24 @@ def SearchBackend(params):
from .mysql.mysql import MySQLSearchBackend
return MySQLSearchBackend(params)
elif connection.vendor == 'sqlite':
- from .sqlite.utils import fts5_available
- if fts5_available():
+ global USE_SQLITE_FTS
+
+ if USE_SQLITE_FTS is None:
+ from .sqlite.utils import fts5_available, fts_table_exists
+ if not fts5_available():
+ USE_SQLITE_FTS = False
+ elif not fts_table_exists():
+ USE_SQLITE_FTS = False
+ warnings.warn(
+ "The installed SQLite library supports full-text search, but the table for storing "
+ "searchable content is missing. This probably means SQLite was upgraded after the "
+ "migration was applied. To enable full-text search, reapply wagtailsearch migration 0006 "
+ "or create the table manually."
+ )
+ else:
+ USE_SQLITE_FTS = True
+
+ if USE_SQLITE_FTS:
from .sqlite.sqlite import SQLiteSearchBackend
return SQLiteSearchBackend(params)
else:
diff --git a/wagtail/search/backends/database/sqlite/utils.py b/wagtail/search/backends/database/sqlite/utils.py
index fb4e0326f3..cb9a75171c 100644
--- a/wagtail/search/backends/database/sqlite/utils.py
+++ b/wagtail/search/backends/database/sqlite/utils.py
@@ -20,3 +20,16 @@ def fts5_available():
tmp_db.close()
return True
+
+
+def fts_table_exists():
+ from wagtail.search.models import SQLiteFTSIndexEntry
+
+ try:
+ # ignore result of query; we are only interested in the query failing,
+ # not the presence of index entries
+ SQLiteFTSIndexEntry.objects.exists()
+ except OperationalError:
+ return False
+
+ return True