Introduce the ability to automatically standup an HTTP proxy for the REST Client

[geoand]

Add HTTP Proxy Dev Service for REST Client

The quarkus-rest-client starts a simple pass-through proxy by default
which can be used as a target for Wireshark (or similar tools)
in order to capture all the traffic originating from the REST Client
(this really makes sense when the REST Client is used against
HTTPS services).

However, advanced integrations that build on the REST Client can
register their own proxies by using the
DevServicesRestClientProxyProvider SPI

P.S. Originally discussed in an email sent to Quarkus Dev.

[maxandersen]

I like the idea but feels "wrong" its at the just the rest client level...shouldn't it be vert.x http or even more globally?

like quarkus.http.devproxy=true ?

[geoand]

The problem is that with anything not managed (Vertx HTTP Client, JDK HTTP Client, Jakarta REST Client) you don't know what the URL is.
With the REST Client you already have all the information available to make this a one flag opt-in process

[maxandersen]

The problem is that with anything not managed (Vertx HTTP Client, JDK HTTP Client, Jakarta REST Client) you don't know what the URL is.

okey - educate me here - why is that important to know? the URL gets requested via the proxy does it not?

[geoand]

why is that important to know? the URL gets requested via the proxy does it not?

This is not using the HTTP proxy headers - I tried that approach and could not get it to work with OpenAI's API so I abandoned it in favor of switching the URL under the covers.

[geoand]

One piece of feedback I had was to make the boundaries of the infrastructure layer for swapping out the URL of the REST Client and the code that actually does something with that URL (which in this case is to create the Vert.x HTTP Proxy). We could imagine that infrastructure could be used to run something like Wiremock or Microcks

[geoand]

@cescoffier what do you want to do with this one?

[cescoffier]

I still need to review it - it's on my list for this week. Sorry for the delay.

[geoand]

No problem at all, just asking :)

[quarkus-bot]

Status for workflow Quarkus CI

This is the status report for running Quarkus CI on commit 420d44c.

✅ The latest workflow run for the pull request has completed successfully.

It should be safe to merge provided you have a look at the other checks in the summary.

You can consult the Develocity build scans.

---

Flaky tests - Develocity

⚙️ Native Tests - HTTP

📦 integration-tests/rest-client-reactive

✖ io.quarkus.it.rest.client.BasicTestIT.shouldCreateClientSpans - History

• expected: <1> but was: <2> - org.opentest4j.AssertionFailedError

org.opentest4j.AssertionFailedError: expected: <1> but was: <2>
	at io.quarkus.it.rest.client.BasicTest.shouldCreateClientSpans(BasicTest.java:216)
	at java.base/java.lang.reflect.Method.invoke(Method.java:568)
	at io.quarkus.test.junit.QuarkusTestExtension.interceptTestMethod(QuarkusTestExtension.java:812)
	at java.base/java.util.ArrayList.forEach(ArrayList.java:1511)
	at java.base/java.util.ArrayList.forEach(ArrayList.java:1511)

[geoand]

Should we include this in 3.13 despite the CR having been released already?

I personally think it's completely safe

[cescoffier]

No problem with me.