Fix circuit breaker Feign builder direct usage

[hutiefang76]

Fixes gh-1210.

When the circuit breaker Feign.Builder bean is used directly, it currently gets created without the CircuitBreakerFactory, group setting, or CircuitBreakerNameResolver that the normal Feign client targeter path applies later. That makes the direct builder path fail at invocation time instead of behaving like the regular circuit breaker Feign client path.

This change configures the circuit breaker builder bean with the available factory, group flag, and resolver. It also falls back to the Feign target name when the builder is used outside the named Feign client targeter path.

Tests added for:

• direct Feign.Builder bean configuration with circuit breaker enabled
• fallback resolver behavior when no resolver bean is available
• using the target name when feignClientName is not set

Tested with:

./mvnw -pl spring-cloud-openfeign-core -Dtest=FeignAutoConfigurationTests test

[Copilot]

Pull request overview

This pull request fixes gh-1210 by ensuring the circuit breaker Feign.Builder bean is fully configured (factory, group flag, and name resolver) when it is used directly, so it behaves consistently with the normal Feign client targeter path. It also makes circuit breaker name/group resolution work when the builder is used outside the named Feign client path by falling back to the Feign Target name.

Changes:

• Configure the circuit-breaker Feign.Builder bean with CircuitBreakerFactory, group-enabled flag, and a resolver fallback when no CircuitBreakerNameResolver bean is present.
• Update FeignCircuitBreakerInvocationHandler to use target.name() when feignClientName is not set (for direct builder usage).
• Add tests covering direct builder configuration and target-name fallback behavior.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
spring-cloud-openfeign-core/src/test/java/org/springframework/cloud/openfeign/FeignAutoConfigurationTests.java	Adds tests for direct circuit breaker builder configuration and target-name fallback behavior.
spring-cloud-openfeign-core/src/main/java/org/springframework/cloud/openfeign/FeignClientsConfiguration.java	Configures the circuit breaker Feign.Builder bean with factory/group/resolver (including a default resolver fallback).
spring-cloud-openfeign-core/src/main/java/org/springframework/cloud/openfeign/FeignCircuitBreakerInvocationHandler.java	Falls back to target.name() when feignClientName is null for circuit/group naming.

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[hutiefang76]

The current head verifies the fallback behavior directly. The direct builder test obtains the resolver from the builder, asserts the default AlphanumericCircuitBreakerNameResolver, and invokes it with a real target and method. The disabled-property variant verifies DefaultCircuitBreakerNameResolver and the unmodified config key. Verified with the focused module test: 11 tests, 0 failures/errors.

[ryanjbaxter]

Technically I believe the fallback name resolver would be AlphanumericCircuitBreakerNameResolver by default if alphanumeric-ids.enabled has matchIfMissing = true. We should probably check that property and use the correct name resolver

[hutiefang76]

The fallback now follows spring.cloud.openfeign.circuitbreaker.alphanumeric-ids.enabled: it uses AlphanumericCircuitBreakerNameResolver when enabled or omitted, and DefaultCircuitBreakerNameResolver when disabled. Both cases are exercised by the direct-builder tests. Verified with the focused module test: 11 tests, 0 failures/errors.

[ryanjbaxter]

Can you introduce a new public method with the new parameter and delegate to that? I do not want to change the signature of public methods

[hutiefang76]

The no-argument public bean method is preserved and delegates to the overload that accepts the configuration values. The test verifies that the public no-argument circuitBreakerFeignBuilder method remains present. Verified with the focused module test: 11 tests, 0 failures/errors.

[ryanjbaxter]

Please sign your commits so the DCO passes

[ryanjbaxter]

Remove

        @Bean
		@Scope("prototype")
		@ConditionalOnMissingBean
		@ConditionalOnBean(CircuitBreakerFactory.class)

From the old method, add them here and then inject the beans you need instead of autowiring them

[ryanjbaxter]

I think we should probably create a Properties class for these, the group property is already used in FeignAutoConfiguration

[ryanjbaxter]

Can you rebase the PR?

[hutiefang76]

@ryanjbaxter Rebased onto the current main and addressed the requested configuration cleanup.

• Added FeignCircuitBreakerProperties for the existing group.enabled and alphanumeric-ids.enabled settings, shared by the targeter and builder.
• Moved the prototype builder bean annotations to the injected overload; the existing public no-arg method remains available.
• Removed field injection from the circuit-breaker builder configuration.
• Extended the tests to assert the actual injected bean method and both resolver behaviors.

Validation: ./mvnw -pl spring-cloud-openfeign-core -Dtest=FeignAutoConfigurationTests test passes (11 tests). I also ran the full core module; its two remaining failures are in FeignClientCacheTests, which expects UnknownHostException for the external fake host foo, while this local network resolves it and returns NoHttpResponseException.

[ryanjbaxter]

Same overload pattern needs to be applied here

[ryanjbaxter]

PR build passes, one small change