8289291: HttpServer sets incorrect value for "max" parameter in Keep-Alive header value

[jaikiran]

Can I please get a review for this change which addresses https://bugs.openjdk.org/browse/JDK-8289291?

As noted in that issue, right now, the Http(s)Server sets an incorrect value for the max parameter of the Keep-Alive header. The max value is supposed to be the number of subsequent requests that the server is willing to serve over that specific connection. The current value it sets is instead the number of idle connections that are configured for the server.

The commit in this PR removes that max parameter altogether, since it isn't mandated by the spec, nor does the Http(s)Server have any specific construct to come up with a right value. Furthermore, on the client side the HttpURLConnection based client doesn't mandate the presence of this parameter in the Keep-Alive header. So this change won't cause any regressions in that area.

tier1, tier2 and tier3 testing passed without any related issues after this change.

---

Progress

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Issue

• JDK-8289291: HttpServer sets incorrect value for "max" parameter in Keep-Alive header value

Reviewers

• Michael McMahon (@Michael-Mc-Mahon - Reviewer)
• Daniel Fuchs (@dfuch - Reviewer)

Reviewing

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[openjdk]

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[mlbridge]

Webrevs

• 01: Full - Incremental (1863de24)
• 00: Full (5bd9ebd0)

[Michael-Mc-Mahon]

Code change looks fine. Could we add a test (even to an existing keepalive one) to verify that "max" is no longer sent?

[jaikiran]

Could we add a test (even to an existing keepalive one) to verify that "max" is no longer sent?

Done. I've updated the PR to include a new test which verifies the absence of the max parameter in the Keep-Alive response header. The test fails without the fix in this PR and passes with the fix.

[Michael-Mc-Mahon]

Looks fine. Thanks!

[openjdk]

@jaikiran This change now passes all automated pre-integration checks.

ℹ️ This project also has non-automated pre-integration requirements. Please see the file CONTRIBUTING.md for details.

After integration, the commit message for the final commit will be:

8289291: HttpServer sets incorrect value for "max" parameter in Keep-Alive header value

Reviewed-by: michaelm, dfuchs

You can use pull request commands such as /summary, /contributor and /issue to adjust it as needed.

At the time when this comment was updated there had been 4 new commits pushed to the master branch:

• 0709a6a: 8284942: Proxy building can just iterate superinterfaces once
• 2961b7e: 8285364: Remove REF_ enum for java.lang.ref.Reference
• 167ce4d: 8289421: No-PCH build for Minimal VM was broken by JDK-8287001
• 108cd69: 8283726: x86_64 intrinsics for compareUnsigned method in Integer and Long

Please see this link for an up-to-date comparison between the source branch of this pull request and the master branch.
As there are no conflicts, your changes will automatically be rebased on top of these commits when integrating. If you prefer to avoid this automatic rebasing, please check the documentation for the /integrate command for further details.

➡️ To integrate this PR with the above commit message to the master branch, type /integrate in a new comment.

[dfuch]

Just wondering about using a simple Socket as the client (which is fine). I'd expect it should be possible to see the value of the header with the new HttpClient (unless we filter it?).

[jaikiran]

Just wondering about using a simple Socket as the client (which is fine). I'd expect it should be possible to see the value of the header with the new HttpClient (unless we filter it?).

The Http(s)Server will set the Keep-Alive header only if the incoming request is a HTTP/1.0 version https://github.com/openjdk/jdk/blob/master/src/jdk.httpserver/share/classes/sun/net/httpserver/ServerImpl.java#L668. The new HttpClient (and even the old HttpURLConnection) both use a minimum of HTTP 1.1 for requests. So the server won't exercise this piece of code for setting the Keep-Alive header, if we use either the new HttpClient or the HttpURLConnection.

[jaikiran]

Thank you Michael and Daniel for the reviews.

[jaikiran]

/integrate

[openjdk]

Going to push as commit dddd4e7.
Since your change was applied there have been 11 commits pushed to the master branch:

• 048bffa: Merge
• cf71544: 8289252: Recommend Locale.of() method instead of the constructor
• 5708974: 8288596: Random:from() adapter does not delegate to supplied generator in all cases
• dbc6e11: 8289399: Update SourceVersion to use snippets
• 15efb2b: 8289238: Refactoring changes to PassFailJFrame Test Framework
• b6bd190: 8288985: P11TlsKeyMaterialGenerator should work with ChaCha20-Poly1305
• ba670ec: 8289094: [JVMCI] reduce JNI overhead and other VM rounds trips in JVMCI
• 0709a6a: 8284942: Proxy building can just iterate superinterfaces once
• 2961b7e: 8285364: Remove REF_ enum for java.lang.ref.Reference
• 167ce4d: 8289421: No-PCH build for Minimal VM was broken by JDK-8287001
• ... and 1 more: https://git.openjdk.org/jdk/compare/b96ba19807845739b36274efb168dd048db819a3...master

Your commit was automatically rebased without conflicts.

[openjdk]

@jaikiran Pushed as commit dddd4e7.

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