fix(command-dev): replace deprecated static-server dep by fastify-static

[tinfoil-knight]

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Summary

Fixes #4511

The static-server dependency which is currently being used by the netlify dev command is now deprecated. This PR intends to replace the dependency with fastify-static (recommended by @lukasholzer).

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[github-actions]

📊 Benchmark results

Comparing with e1f661a

Package size: 259 MB

⬆️ 6.60% increase vs. e1f661a

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└───┴──┴────┴──┴────┴──┴────┴──┴────┴──┴────┴──┴────┴──┴────┴──┴────┴──┴────┴──┴────┴──┴────┴──┴────┴──┴──>
    T-12    T-11    T-10    T-9     T-8     T-7     T-6     T-5     T-4     T-3     T-2     T-1      T    

Legend

• T-30 (62930d8): 254 MB
• T-29 (345ce9c): 254 MB
• T-28 (0041559): 254 MB
• T-27 (e65f97c): 254 MB
• T-26 (35123df): 254 MB
• T-25 (a49e5fc): 249 MB
• T-24 (6214768): 242 MB
• T-23 (acdcbb6): 242 MB
• T-22 (743b4d6): 242 MB
• T-21 (f9f45ed): 249 MB
• T-20 (22de9e2): 249 MB
• T-19 (d64c875): 249 MB
• T-18 (cd993b0): 249 MB
• T-17 (9a7c666): 249 MB
• T-16 (cf2f402): 249 MB
• T-15 (6102e77): 249 MB
• T-14 (d3dfa17): 249 MB
• T-13 (9bb51a1): 249 MB
• T-12 (81ac0c6): 249 MB
• T-11 (bb16cec): 249 MB
• T-10 (3ff4a57): 249 MB
• T-9 (3b491be): 249 MB
• T-8 (0bc18bb): 249 MB
• T-7 (12664f3): 249 MB
• T-6 (7ebf238): 249 MB
• T-5 (df9260a): 249 MB
• T-4 (e3db314): 249 MB
• T-3 (7eb4479): 249 MB
• T-2 (89b14e2): 249 MB
• T-1 (e1f661a): 242 MB
• T (current commit): 259 MB

[tinfoil-knight]

Relevant Documentation:

• fastify : https://www.fastify.io/docs/latest/Reference/
  - https://www.fastify.io/docs/latest/Reference/Hooks/#onrequest
  - https://www.fastify.io/docs/latest/Reference/Server/#setnotfoundhandler
• @fastify/static : https://github.com/fastify/fastify-static

[tinfoil-knight]

Change in Response Headers

• For successful request OR not found requests with 404.html file present:
  cache-control (public, max-age=0) is added.

• For not found requests without any 404.html file:
  transfer-encoding (chunked) is not there now.

• content-type for responses with a file has changed from text/html to text/html; charset=UTF-8

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Note
In production Netlify, cache-control is public, max-age=0, must-revalidate.

[tinfoil-knight]

ETag generation is disabled since the proxy already handles that.

[tinfoil-knight]

The name: 'netlify-dev' configuration in static-server used to set the X-Powered-by header which is now being done manually here.

[danez]

Awesome. Happy new year.
I was already thinking about doing this. and even replacing express everywhere, but that would be a much bigger task I think.

[kodiakhq]

This PR currently has a merge conflict. Please resolve this and then re-add the automerge label.

[tinfoil-knight]

Awesome. Happy new year.

Happy new year to you too @danez. It was fun working w/ you & other folks on the Netlify team past year.