JDK 11 HttpClient integration with WebClient

[Julien-Eyraud]

This a simple implementation of ClientHttpResponse that levrage
JDK 11 HttpClient.

Closes gh-21014

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[rstoyanchev]

Cross-linking to #17778 that this depends on.

[rdsubhas]

@Julien-Eyraud amazing feature :) would be awesome to resolve conflicts and see this merged...

[Julien-Eyraud]

@rdsubhas I won't fix merge until #17778 is fixed

[candrews]

I've created a Spring Boot starter using the code from this PR: https://github.com/candrews/java-httpclient-webclient-spring-boot-starter.

It provides a really simple way to configure WebClient to use Java 11's HttpClient; just add the dependency (which I've published to Maven Central) to your project and you're done.

Hopefully, it helps those of us who really would like this feature hold out until it lands in Spring itself :)

[curena]

So, is this still happening?

[Julien-Eyraud]

I don't know I can update the PR to fix conflict and change the target branch. It's up to the maintainer now.

[rstoyanchev]

The main branch is on JDK 17 now, so we can move forward with this.

[Julien-Eyraud]

I've rebase my branch on main. I've updated the JdkClientHttpResponse#getCookies with a duplicate from JettyClientHttpResponse#parseSameSite. I didn't know where to but it to use a common code. I also updated the documentation.

[rk99d339]

I just saw your JdkClientHttpConnector pullrequest.
Please add it here as default if no other is on the classpath org.springframework.web.reactive.function.client.DefaultWebClientBuilder.initConnector()
instead of throwing an Exception
throw new IllegalStateException("No suitable default ClientHttpConnector found");

A problem is that child classes of AbstractWebClientReactiveOAuth2AccessTokenResponseClient
Always creates a new Webclient with:
private WebClient webClient = WebClient.builder().build();
which invokes the DefaultWebClientBuilder.initConnector() leading to the IllegalStateException.

Or at least add a Constructor to AbstractWebClientReactiveOAuth2AccessTokenResponseClient which takes a preinitialized WebClient instead of creating a new one.

Sincerely
Rolf

[Julien-Eyraud]

It's an interesting point @rk99d339. I'll wait for maintainer feedback. I hope I'll be able to merge soon.

[Julien-Eyraud]

Hi @rstoyanchev do you think I can have a review soon ? Or this will be discard ? What do you think about rk99d339's comment ?

[rstoyanchev]

Yes, I'm reviewing this and should have an update soon.

[rstoyanchev]

This is now in main. I've also made sure the JDK client is used by default when no others are present.