[Improvement-18611][Task] Support configurable TCP keepalive on the H…

[Admaing]

Was this PR generated or assisted by AI?

Yes. The OkHttpUtils keepalive overloads and part of the unit tests were drafted with AI help. I reviewed the whole diff myself, ran the tests and spotless locally, and confirmed the default stays false.

Ref: #18611

Purpose of the pull request

Add an opt-in TCP keepalive (SO_KEEPALIVE) switch to the HTTP task.

Some HTTP tasks fail with Read timed out when the worker sits behind a NAT or firewall that drops idle TCP sessions. curl works in the same setup because it enables keepalive by default, while OkHttp does not. The option defaults to false, so existing tasks are unaffected.

Brief change log

• HttpParameters: new socketKeepAlive field, default false.
• OkHttpUtils: get/post/put/delete overloads with a keepalive flag; the old
  overloads are unchanged.
• HttpTask: pass the flag through for GET/POST/PUT/DELETE.
• UI: switch in the HTTP task form, plus en_US/zh_CN labels.

Verify this pull request

This change added tests and can be verified as follows:

• HttpParametersTest: default value and serialization round-trip.
• HttpTaskTest: GET/POST/DELETE against a MockWebServer with keepalive on.
• ./mvnw -pl dolphinscheduler-task-plugin/dolphinscheduler-task-http -am test -Dtest=HttpTaskTest,HttpParametersTest -Dsurefire.failIfNoSpecifiedTests=false
  → Tests run: 16, Failures: 0, Errors: 0.
• ./mvnw -pl dolphinscheduler-common,dolphinscheduler-task-plugin/dolphinscheduler-task-http spotless:check
  passes.

Pull Request Notice

Pull Request Notice

No incompatible change, so incompatible.md is unchanged.

[boring-cyborg]

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[SbloodyS]

You are using AI to create PR and did not follow the pull request template.

[Admaing]

You are using AI to create PR and did not follow the pull request template.

Sorry, I didn't follow the PR template. Updated it now.

[SbloodyS]

** Separate connection pools for enabled and disabled TCP keepalive**

OkHttpUtils.java:315–320 derives both client variants from CLIENT.newBuilder(), which shares the original connection pool. In OkHttp 4.12.0, connection eligibility uses Address.equalsNonHost(), which does not compare the plain socketFactory.

If a request with keepalive disabled leaves a reusable connection in the pool, a subsequent keepalive-enabled request to the same origin can reuse that socket without invoking KEEP_ALIVE_SOCKET_FACTORY. TCP keepalive remains disabled, so the new option does not reliably address the idle-connection failure. The reverse also occurs: disabled requests can reuse enabled sockets.

Please maintain separate reusable pools for the two settings. Add a regression test that sends consecutive requests to the same origin with different settings and verifies the actual socket keepalive state; successful responses alone do not verify this behavior.

[Admaing]

** Separate connection pools for enabled and disabled TCP keepalive**

OkHttpUtils.java:315–320 derives both client variants from CLIENT.newBuilder(), which shares the original connection pool. In OkHttp 4.12.0, connection eligibility uses Address.equalsNonHost(), which does not compare the plain socketFactory.

If a request with keepalive disabled leaves a reusable connection in the pool, a subsequent keepalive-enabled request to the same origin can reuse that socket without invoking KEEP_ALIVE_SOCKET_FACTORY. TCP keepalive remains disabled, so the new option does not reliably address the idle-connection failure. The reverse also occurs: disabled requests can reuse enabled sockets.

Please maintain separate reusable pools for the two settings. Add a regression test that sends consecutive requests to the same origin with different settings and verifies the actual socket keepalive state; successful responses alone do not verify this behavior.

Confirmed — Address.equalsNonHost$okhttp ignores socketFactory, so the shared pool made the option unreliable in both directions. KEEP_ALIVE_CLIENT is now built from new OkHttpClient().newBuilder() so it has its own ConnectionPool, and getHttpClient(...) picks the base client by the flag.

OkHttpUtilsTest sends consecutive requests to the same origin with different settings, and asserts the other setting's pooled connection count stays 0, that the keepalive client's socket factory produces a socket with getKeepAlive() == true, and (recorded on the test server) that the two requests did not share one TCP connection. It fails if I revert to a shared pool.

getHttpClient(...) is now package-private + @VisibleForTesting so the test stays on public OkHttp APIs instead of reflecting into okhttp3.internal.*.