Summary

Following discussion in discourse, this PR shows the triggering of notAcceptable happening from the middleware before any of the dispatchers are triggered, since they should only be triggered if they would actually be acceptable and lead to a response.

This means that when you're passing through requests via content-negotiation, the fedify dispatcher is not fired if it's not a Accept content-type that fedify would actually handle.

This would be a major breaking change, hence targeting next

Related Issue

There doesn't seem to be related issues reported, however, it's a common point of confusion for integraters "why is my fedify dispatcher firing for this html request?"

Changes

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• Lifted check for Accept header content-type up to middleware
• Moved acceptsJsonLd to negotiation.ts (from handle.ts)
• Removed old notAcceptable tests from handler.test.ts — I'm still not 100% sure how these tests were working.

Benefits

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Checklist

• Did you add a changelog entry to the CHANGES.md?
• Did you write some relevant docs about this change (if it's a new feature)?
• Did you write a regression test to reproduce the bug (if it's a bug fix)?
• Did you write some tests for this change (if it's a new feature)?
• Did you run deno task test-all on your machine?

Additional Notes

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