Allow Node TLS's 'alpnProtocol' to be false

[pimterry]

Tiny change: as documented (in the node docs and the comment already present here) alpnProtocol is false when no ALPN protocol is selected.

I've left undefined here too, as it was before - I'm not sure if that can occur in some cases as well, e.g. when ALPN isn't configured at all, or isn't supported in the TLS version, etc.

---

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[typescript-bot]

@pimterry Thank you for submitting this PR!

This is a live comment which I will keep updated.

1 package in this PR

• node — on npm, on unpkg
  • owner-approval: @peterblazejewicz, @LinusU

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[typescript-bot]

Hey @pimterry,

😒 Your PR doesn't modify any tests, so it's hard to know what's being fixed, and your changes might regress in the future. Please consider adding tests to cover the change you're making. Including tests allows this PR to be merged by yourself and the owners of this module.

This can potentially save days of time for you!

[typescript-bot]

🔔 @microsoft @DefinitelyTyped @jkomyno @alvis @r3nya @btoueg @smac89 @Touffy @DeividasBakanas @eyqs @Hannes-Magnusson-CK @hoo29 @kjin @ajafff @islishude @mwiktorczyk @mohsen1 @n-e @galkin @parambirs @eps1lon @SimonSchick @ThomasdenH @WilcoBakker @wwwy3y3 @samuela @kuehlein @bhongy @chyzwar @trivikr @nguymin4 @yoursunny @qwelias @ExE-Boss @Ryan-Willpower @peterblazejewicz @addaleax @JasonHK @victorperin @ZYSzys @nodejs @LinusU — please review this PR in the next few days. Be sure to explicitly select Approve or Request Changes in the GitHub UI so I know what's going on.

[peterblazejewicz]

This needs to be amended in both LTS version IMO

[LinusU]

👍

[pimterry]

This needs to be amended in both LTS version IMO

Done

I've also investigated the possible values further. It's not formally documented, but the actual 'not yet set' value is null, not undefined, so I've updated the types to match. That can be seen by:

• Initally set to null: https://github.com/nodejs/node/blob/ea47d836403fa055861b01ea791f9b2da7ee7e7e/lib/_tls_wrap.js#L489
• Later set from getALPNNegotiatedProtocol: https://github.com/nodejs/node/blob/ea47d836403fa055861b01ea791f9b2da7ee7e7e/lib/_tls_wrap.js#L929
• That method always returns a string or false: https://github.com/nodejs/node/blob/e46c680bf2b211bbd52cf959ca17ee98c7f657f5/src/crypto/crypto_tls.cc#L1969-L1993

[peterblazejewicz]

LGTM!

[typescript-bot]

@pimterry: Everything looks good here. I am ready to merge this PR (at 6dd579e) on your behalf whenever you think it's ready.

If you'd like that to happen, please post a comment saying:

Ready to merge

and I'll merge this PR almost instantly. Thanks for helping out! ❤️

(@microsoft, @DefinitelyTyped, @jkomyno, @alvis, @r3nya, @btoueg, @smac89, @Touffy, @DeividasBakanas, @eyqs, @Hannes-Magnusson-CK, @hoo29, @kjin, @ajafff, @islishude, @mwiktorczyk, @mohsen1, @n-e, @galkin, @parambirs, @eps1lon, @SimonSchick, @ThomasdenH, @WilcoBakker, @wwwy3y3, @samuela, @kuehlein, @bhongy, @chyzwar, @trivikr, @nguymin4, @yoursunny, @qwelias, @ExE-Boss, @Ryan-Willpower, @peterblazejewicz, @addaleax, @JasonHK, @victorperin, @ZYSzys, @nodejs, @LinusU: you can do this too.)

[pimterry]

Ready to merge

[typescript-bot]

I just published @types/node@16.7.9 to npm.

[typescript-bot]

I just published @types/node@14.17.13 to npm.

[typescript-bot]

I just published @types/node@12.20.22 to npm.