table.rebuild_fts() method, refs #155

docs/python-api.rst

@@ -1213,6 +1213,21 @@ To remove the FTS tables and triggers you created, use the ``disable_fts()`` tab
 
     dogs.disable_fts()
 
+Rebuilding a full-text search table
+===================================
+
+You can rebuild a table using the ``table.rebuild_fts()`` method. This is useful for if the table configuration changes or the indexed data has become corrupted in some way.
+
+.. code-block:: python
+
+    dogs.rebuild_fts()
+
+This method can be called on a table that has been configured for full-text search - ``dogs`` in this instance -  or directly on a ``_fts`` table:
+
+.. code-block:: python
+
+    db["dogs_fts"].rebuild_fts()
+
 Optimizing a full-text search table
 ===================================
 

sqlite_utils/db.py

@@ -905,6 +905,17 @@ class Table(Queryable):
             for trigger_name in trigger_names:
                 self.db.execute("DROP TRIGGER IF EXISTS [{}]".format(trigger_name))
 
+    def rebuild_fts(self):
+        fts_table = self.detect_fts()
+        if fts_table is None:
+            # Assume this is itself an FTS table
+            fts_table = self.name
+        self.db.execute(
+            "INSERT INTO [{table}]([{table}]) VALUES('rebuild');".format(
+                table=fts_table
+            )
+        )
+
     def detect_fts(self):
         "Detect if table has a corresponding FTS virtual table and return it"
         sql = (

tests/test_fts.py

@@ -1,4 +1,5 @@
 import pytest
+from sqlite_utils.utils import sqlite3
 
 search_records = [
     {
@@ -173,3 +174,28 @@ def test_disable_fts(fresh_db, create_triggers):
         ).fetchone()[0]
     )
     assert ["searchable"] == fresh_db.table_names()
+
+
+@pytest.mark.parametrize("table_to_fix", ["searchable", "searchable_fts"])
+def test_rebuild_fts(fresh_db, table_to_fix):
+    table = fresh_db["searchable"]
+    table.insert(search_records[0])
+    table.enable_fts(["text", "country"])
+    # Run a search
+    assert [("tanuki are running tricksters", "Japan", "foo")] == table.search("tanuki")
+    # Delete from searchable_fts_data
+    fresh_db["searchable_fts_data"].delete_where()
+    # This should have broken the index
+    with pytest.raises(sqlite3.DatabaseError):
+        table.search("tanuki")
+    # Running rebuild_fts() should fix it
+    fresh_db[table_to_fix].rebuild_fts()
+    assert [("tanuki are running tricksters", "Japan", "foo")] == table.search("tanuki")
+
+
+@pytest.mark.parametrize("invalid_table", ["does_not_exist", "not_searchable"])
+def test_rebuild_fts_invalid(fresh_db, invalid_table):
+    fresh_db["not_searchable"].insert({"foo": "bar"})
+    # Raise OperationalError on invalid table
+    with pytest.raises(sqlite3.OperationalError):
+        fresh_db[invalid_table].rebuild_fts()