[dagit] redirect trailing slash on GraphQL route

[benpankow]

Summary

Adds a redirect from the graphql URL with a trailing slash: localhost:3000/graphql/->localhost:3000/graphql. A user recently ran into this: https://elementl-workspace.slack.com/archives/C046ZK3KQ5D/p1679944131264839?thread_ts=1679942695.590929&cid=C046ZK3KQ5D

[benpankow]

• [dagit] redirect trailing slash on GraphQL route #13181 👈 (View in Graphite)
• master

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[brad-alexander]

A compelling reason to omit the redirect (or make it optional) would be to prevent accidental performance issues. It looks like even if you use sessions in requests, it does not remember 307 or even 308 responses, and will always make two roundtrips for every request. This probably wouldn't be much of a hit if the server is on the same network, but if the server is under significant load, or over slow WAN/VPN it could be significant overhead - especially if it is a large POST request.

[alangenfeld]

should we take an approach similar to what we did here and just dupe the routes instead
https://github.com/dagster-io/internal/pull/876/files

[alangenfeld]

to your queue

[alangenfeld]

related encode/starlette#869 though that doesn't necessarily help much