fix: set host header for requests from HTTP2 to HTTP1

[sapphi-red]

Requests from HTTP2 had a different header values for Host and X-Forward-* from requests from HTTP 1.x. This PR fixes that inconsistency.

related vitejs/vite#21117

[Corvince]

At first I was happy to have contributed (indirectly) to vite, but the responsibility certainly feels different 😆

Feel free to tag me in the future for issues related to http2, I wasn't aware of the scale of the problem, only saw the forward header briefly mentioned in #2 and fixed in #42 (which does not include the other fixes present in this PR).

[Copilot]

Pull request overview

This PR fixes inconsistencies in the Host and X-Forwarded-* headers when proxying requests from HTTP/2 to HTTP/1. The fix ensures that the HTTP/2 :authority pseudo-header is properly converted to the Host header for HTTP/1 backends.

• Adds support for HTTP/2 :authority pseudo-header across the proxy pipeline
• Updates header handling in setupOutgoing, XHeaders, getPort, and setRedirectHostRewrite functions
• Includes comprehensive test coverage for HTTP/2 to HTTP/1 proxy scenarios

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
lib/http-proxy/common.ts	Maps HTTP/2 :authority header to host header for outgoing HTTP/1 requests and updates port extraction logic
lib/http-proxy/passes/web-incoming.ts	Uses :authority as fallback for x-forwarded-host header in HTTP/2 requests
lib/http-proxy/passes/web-outgoing.ts	Supports :authority header in redirect host rewrite logic for HTTP/2 requests; removes trailing whitespace
lib/test/lib/http2-proxy.test.ts	Adds new integration tests for HTTP/2 to HTTP/1 proxy scenarios using both proxy server and custom HTTP/2 server
lib/test/lib/http-proxy-passes-web-incoming.test.ts	Adds unit test verifying correct x-forwarded-* header handling for HTTP/2 requests
lib/test/lib/http-proxy-passes-web-outgoing.test.ts	Adds unit test for redirect host rewrite with HTTP/2 :authority header

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[Copilot]

The HTTP2 client connection should be closed to prevent resource leaks. Add client.close() before calling done(). For example:

req.on('end', () => {
  source.close();
  proxy.close();
  client.close();
  done();
});

Suggested change

	proxy.close();
	proxy.close();
	client.close();

[Copilot]

The HTTP2 client connection should be closed to prevent resource leaks. Add client.close() before calling done(). For example:

req.on('end', () => {
  source.close();
  ownServer.close();
  client.close();
  done();
});

Suggested change

	ownServer.close();
	ownServer.close();
	client.close();

[williamstein]

@sapphi-red sorry about that. I've made a release including this -- 1.23.1 .

[williamstein]

Regarding the copilot AI review, I think they are useful as a sort of linter. In this case, I don't care about potential leaks in unit tests, which is all it flagged.