html_url,issue_url,id,node_id,user,created_at,updated_at,author_association,body,reactions,issue,performed_via_github_app
https://github.com/simonw/datasette/issues/1949#issuecomment-1352411327,https://api.github.com/repos/simonw/datasette/issues/1949,1352411327,IC_kwDOBm6k_c5QnCi_,9599,2022-12-15T00:46:27Z,2022-12-15T00:46:27Z,OWNER,"I got this far:
```diff
diff --git a/datasette/handle_exception.py b/datasette/handle_exception.py
index 8b7e83e3..31d41e00 100644
--- a/datasette/handle_exception.py
+++ b/datasette/handle_exception.py
@@ -54,7 +54,17 @@ def handle_exception(datasette, request, exception):
         headers = {}
         if datasette.cors:
             add_cors_headers(headers)
-        if request.path.split(""?"")[0].endswith("".json""):
+        # Return JSON error under certain conditions
+        should_return_json = (
+            # URL ends in .json
+            request.path.split(""?"")[0].endswith("".json"")
+            or
+            # Hints from incoming request headers
+            request.headers.get(""content-type"") == ""application/json""
+            or ""application/json"" in request.headers.get(""accept"", """")
+        )
+        breakpoint()
+        if should_return_json:
             return Response.json(info, status=status, headers=headers)
         else:
             template = datasette.jinja_env.select_template(templates)
diff --git a/tests/test_api_write.py b/tests/test_api_write.py
index f27d143f..982543a6 100644
--- a/tests/test_api_write.py
+++ b/tests/test_api_write.py
@@ -1140,6 +1140,38 @@ async def test_create_table_permissions(
         assert data[""errors""] == expected_errors
 
 
+@pytest.mark.asyncio
+@pytest.mark.parametrize(
+    ""headers,expect_json"",
+    (
+        ({}, False),
+        ({""Accept"": ""text/html""}, True),
+        ({""Accept"": ""application/json""}, True),
+        ({""Content-Type"": ""application/json""}, True),
+        ({""Accept"": ""application/json, text/plain, */*""}, True),
+        ({""Content-Type"": ""application/json""}, True),
+        ({""accept"": ""application/json, text/plain, */*""}, True),
+        ({""content-type"": ""application/json""}, True),
+    ),
+)
+async def test_permission_errors_html_and_json(ds_write, headers, expect_json):
+    request_headers = {""Authorization"": ""Bearer bad_token""}
+    request_headers.update(headers)
+    response = await ds_write.client.post(
+        ""/data/-/create"",
+        json={},
+        headers=request_headers,
+    )
+    assert response.status_code == 403
+    if expect_json:
+        data = response.json()
+        assert data[""ok""] is False
+        assert data[""errors""] == [""Permission denied""]
+    else:
+        assert response.headers[""Content-Type""] == ""text/html; charset=utf-8""
+        assert ""Permission denied"" in response.text
+
+
 @pytest.mark.asyncio
 @pytest.mark.parametrize(
     ""input,expected_rows_after"",
```
Then decided I would punt this until the next milestone.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",1493471221,
https://github.com/simonw/datasette/issues/1949#issuecomment-1352378370,https://api.github.com/repos/simonw/datasette/issues/1949,1352378370,IC_kwDOBm6k_c5Qm6gC,9599,2022-12-15T00:02:08Z,2022-12-15T00:04:54Z,OWNER,"I fixed this issue to help research this further:
- https://github.com/simonw/datasette-ripgrep/issues/26

Now this search works:

<https://ripgrep.datasette.io/-/ripgrep?pattern=return+_error&literal=on&glob=datasette%2F**>

I wish I had this feature!
- https://github.com/simonw/datasette-ripgrep/issues/24

Looks like I have both `_error()` and `_errors()` functions in there!

<img width=""872"" alt=""image"" src=""https://user-images.githubusercontent.com/9599/207741634-56667a10-ba70-42e0-98ca-ca1444a86e57.png"">
","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",1493471221,