arraynotcontains filter, closes #1132

datasette/filters.py

@@ -154,7 +154,16 @@ class Filters:
             where j.value = :{p}
         )""",
                     '{c} contains "{v}"',
-                )
+                ),
+                TemplatedFilter(
+                    "arraynotcontains",
+                    "array does not contain",
+                    """rowid not in (
+            select {t}.rowid from {t}, json_each({t}.{c}) j
+            where j.value = :{p}
+        )""",
+                    '{c} does not contain "{v}"',
+                ),
             ]
             if detect_json1()
             else []

docs/json_api.rst

@@ -267,7 +267,12 @@ You can filter the data returned by the table based on column values using a que
     Rows where column does not match any of the provided values. The inverse of ``__in=``. Also supports JSON arrays.
 
 ``?column__arraycontains=value``
-    Works against columns that contain JSON arrays - matches if any of the values in that array match.
+    Works against columns that contain JSON arrays - matches if any of the values in that array match the provided value.
+
+    This is only available if the ``json1`` SQLite extension is enabled.
+
+``?column__arraynotcontains=value``
+    Works against columns that contain JSON arrays - matches if none of the values in that array match the provided value.
 
     This is only available if the ``json1`` SQLite extension is enabled.
 

tests/test_api.py

@@ -1121,7 +1121,7 @@ def test_table_filter_queries_multiple_of_same_type(app_client):
 @pytest.mark.skipif(not detect_json1(), reason="Requires the SQLite json1 module")
 def test_table_filter_json_arraycontains(app_client):
     response = app_client.get("/fixtures/facetable.json?tags__arraycontains=tag1")
-    assert [
+    assert response.json["rows"] == [
         [
             1,
             "2019-01-14 08:00:00",
@@ -1146,7 +1146,28 @@ def test_table_filter_json_arraycontains(app_client):
             "[]",
             "two",
         ],
-    ] == response.json["rows"]
+    ]
+
+
+@pytest.mark.skipif(not detect_json1(), reason="Requires the SQLite json1 module")
+def test_table_filter_json_arraynotcontains(app_client):
+    response = app_client.get(
+        "/fixtures/facetable.json?tags__arraynotcontains=tag3&tags__not=[]"
+    )
+    assert response.json["rows"] == [
+        [
+            1,
+            "2019-01-14 08:00:00",
+            1,
+            1,
+            "CA",
+            1,
+            "Mission",
+            '["tag1", "tag2"]',
+            '[{"foo": "bar"}]',
+            "one",
+        ]
+    ]
 
 
 def test_table_filter_extra_where(app_client):