Fixes #482 No bean found of type Targeter. (#483)

spring-cloud-openfeign-core/src/test/java/org/springframework/cloud/openfeign/FeignAutoConfigurationTests.java

@@ -0,0 +1,107 @@
+/*
+ * Copyright 2013-2020 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.cloud.openfeign;
+
+import feign.hystrix.HystrixFeign;
+import org.assertj.core.api.Condition;
+import org.junit.jupiter.api.Test;
+
+import org.springframework.boot.autoconfigure.AutoConfigurations;
+import org.springframework.boot.test.context.FilteredClassLoader;
+import org.springframework.boot.test.context.runner.ApplicationContextRunner;
+import org.springframework.cloud.client.circuitbreaker.CircuitBreaker;
+import org.springframework.cloud.client.circuitbreaker.CircuitBreakerFactory;
+import org.springframework.context.ConfigurableApplicationContext;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.Mockito.mock;
+
+/**
+ * @author Tim Peeters
+ */
+class FeignAutoConfigurationTests {
+
+	private final ApplicationContextRunner runner = new ApplicationContextRunner()
+			.withConfiguration(AutoConfigurations.of(FeignAutoConfiguration.class));
+
+	@Test
+	void shouldInstantiateHystrixTargeterToMaintainBackwardsCompatibility() {
+		runner.run(ctx -> assertOnlyOneTargeterPresent(ctx, HystrixTargeter.class));
+	}
+
+	@Test
+	void shouldInstantiateHystrixTargeterWhenExplicitlyEnabled() {
+		runner.withPropertyValues("feign.hystrix.enabled=true")
+				.run(ctx -> assertOnlyOneTargeterPresent(ctx, HystrixTargeter.class));
+	}
+
+	@Test
+	void shouldInstantiateDefaultTargeterWhenHystrixIsDisabled() {
+		runner.withPropertyValues("feign.hystrix.enabled=false")
+				.run(ctx -> assertOnlyOneTargeterPresent(ctx, DefaultTargeter.class));
+	}
+
+	@Test
+	void shouldInstantiateDefaultTargeterWhenHystrixFeignClassIsMissing() {
+		runner.withPropertyValues("feign.hystrix.enabled=true")
+				.withClassLoader(new FilteredClassLoader(HystrixFeign.class))
+				.run(ctx -> assertOnlyOneTargeterPresent(ctx, DefaultTargeter.class));
+	}
+
+	@Test
+	void shouldInstantiateDefaultTargeterWhenHystrixFeignAndCircuitBreakerClassesAreMissing() {
+		runner.withPropertyValues("feign.hystrix.enabled=true",
+				"feign.circuitbreaker.enabled=true")
+				.withClassLoader(
+						new FilteredClassLoader(HystrixFeign.class, CircuitBreaker.class))
+				.run(ctx -> assertOnlyOneTargeterPresent(ctx, DefaultTargeter.class));
+	}
+
+	@Test
+	void shouldInstantiateDefaultTargeterWhenHystrixFeignClassIsMissingAndFeignCircuitBreakerIsDisabled() {
+		runner.withClassLoader(new FilteredClassLoader(HystrixFeign.class))
+				.withPropertyValues("feign.circuitbreaker.enabled=false")
+				.run(ctx -> assertOnlyOneTargeterPresent(ctx, DefaultTargeter.class));
+	}
+
+	@Test
+	void shouldInstantiateFeignCircuitBreakerTargeterWhenEnabled() {
+		runner.withBean(CircuitBreakerFactory.class,
+				() -> mock(CircuitBreakerFactory.class))
+				.withPropertyValues("feign.circuitbreaker.enabled=true")
+				.run(ctx -> assertOnlyOneTargeterPresent(ctx,
+						FeignCircuitBreakerTargeter.class));
+	}
+
+	@Test
+	void shouldInstantiateFeignCircuitBreakerTargeterWhenBothHystrixAndCircuitBreakerAreEnabled() {
+		runner.withBean(CircuitBreakerFactory.class,
+				() -> mock(CircuitBreakerFactory.class))
+				.withPropertyValues("feign.hystrix.enabled=true",
+						"feign.circuitbreaker.enabled=true")
+				.run(ctx -> assertOnlyOneTargeterPresent(ctx,
+						FeignCircuitBreakerTargeter.class));
+	}
+
+	private void assertOnlyOneTargeterPresent(ConfigurableApplicationContext ctx,
+			Class<?> beanClass) {
+		assertThat(ctx.getBeansOfType(Targeter.class)).hasSize(1)
+				.hasValueSatisfying(new Condition<>(beanClass::isInstance, String
+						.format("Targeter should be an instance of %s", beanClass)));
+	}
+
+}