setConnectionTimeout on RestTemplateBuilder is not Working

[goafabric]

Imagine the following code

final RestTemplate restTemplate = new RestTemplateBuilder()
.setConnectTimeout(Duration.ofMillis(timeout))
.setReadTimeout(Duration.ofMillis(timeout))
.build();

While working in normal mode, a call inside a Native Image will crash with:
"SimpleClientHttpRequestFactory does not have a suitable setConnectTimeout method"

Would be nice if this can be fixed.

[ttddyy]

Hi,

I just checked why.

The RestTemplateBuilder uses reflection to access setConnectTimeout/setReadTimeout/setBufferRequestBody methods on underlying ClientHttpRequestFactory.

https://github.com/spring-projects/spring-boot/blob/main/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/client/RestTemplateBuilder.java#L760-L784

So those methods need some entries for @TypeHint/reflect-config.json.

[goafabric]

Yes you are right .. wouldn't have thought that this is so easy
A simple
@typehint(types = org.springframework.http.client.SimpleClientHttpRequestFactory.class)

fixes the issue ... would be nice though if RestTemplateBuilder will have this out of the box ..
Thx 4 the quick support.

One more thing .. do you know why all returned classes from a RestTemplate call
also have to be registered for Reflection manually ?
I guess because the JSON (De)Serializer creates them via Reflection ?

Quarkus currently does this automatically for everything annotated with "RegisterRestCLient"

[ttddyy]

I have created a PR to add a type hint for SimpleClientHttpRequestFactory.
#959

One more thing .. do you know why all returned classes from a RestTemplate call
also have to be registered for Reflection manually ?
I guess because the JSON (De)Serializer creates them via Reflection ?

Yeah, I think so.
To map the json string to the target type object, jackson should be constructing the target type dynamically unless custom (de)serializers are used.

I think one way to achieve it would be spring-aot may look for the return types from controllers and automatically register them.
Or, spring-aot may generate serializers that would convert to the target type explicitly without reflection. Just my ideas.

[goafabric]

Thank you