Does querystats support DRF endpoints?

[jmduke]

I'm integrating with querystats, and it looks like QueryStatsMiddleware is failing on any DRF-borne responses:

web       | │                                                                              │
web       | │ /Users/jmduke/Library/Caches/pypoetry/virtualenvs/buttondown-Z98J7QrZ-py3.10 │
web       | │ /lib/python3.10/site-packages/forgequerystats/middleware.py:86 in            │
web       | │ process_template_response                                                    │
web       | │                                                                              │
web       | │    83 │   │   # Template hasn't been rendered yet, so we can't include query │
web       | │    84 │   │   # unless we're pulling the previous page stats from the sessio │
web       | │    85 │   │   if hasattr(_local, "querystats") and self.is_staff_request(req │
web       | │ ❱  86 │   │   │   response.context_data["querystats_enabled"] = True         │
web       | │    87 │   │   │                                                              │
web       | │    88 │   │   │   # Load the previous querystats from the session and displa │
web       | │    89 │   │   │   if request.GET.get("querystats") == "show":                │
web       | │                                                                              │
web       | │ ╭───────────────────────────────── locals ─────────────────────────────────╮ │
web       | │ │  request = <WSGIRequest: GET '/v1/tags'>                                 │ │
web       | │ │ response = <Response status_code=200, "text/html; charset=utf-8">        │ │
web       | │ │     self = <forgequerystats.middleware.QueryStatsMiddleware object at    │ │
web       | │ │            0x1120922f0>                                                  │ │
web       | │ ╰──────────────────────────────────────────────────────────────────────────╯ │
web       | ╰──────────────────────────────────────────────────────────────────────────────╯
web       | TypeError: 'NoneType' object does not support item assignment
web       |

I suspect (but am not positive) that this is because DRF-flavored responses don't support context_data. What are your thoughts? From a selfish perspective, this is only a short-term blocker (I'm migrating to Django-Ninja for those DRF views in the next few weeks) non-template-views in general are often the ones I'm most concerned about from a perf standpoint (my application is largely a Django shell around an SPA that uses remote calls for most orchestration.)

[davegaeddert]

At least in my basic test, this error shows up when you're looking at the browsable API (which makes sense because it would be a template response)? Interesting that they must be setting response.context_data = None. Seems to work fine for me on regular API calls and you can see the querystats in the Server-Timing header:

As a first step I went ahead and added another condition to skip the rendering logic if context_data is None, so the error should be fixed (which also means you won't be able to view the querystats UI on the DRF browsable API right now). You can try forge-querystats v0.2.1 now.

As far as perf goes, this stuff only runs if settings.DEBUG (local dev) or if you're logged in as a staff user, but if we need to add another option/hook to disable it for specific views/urls (or DRF entirely), I'm sure we can do that! DRF isn't a huge priority for me either, so I'm probably not going to pursue anything there right now unless you want me to — just let me know if there are more changes you want to see happen.

[jmduke]

This worked perfectly; thanks for the quick response + action!