ContractVerifierObjectMapper - special support for Avro

spring-cloud-contract-verifier/pom.xml

@@ -5,6 +5,7 @@
 	<modelVersion>4.0.0</modelVersion>
 	<properties>
 		<javax.ws.rs-api.version>2.1.1</javax.ws.rs-api.version>
+		<avro.version>1.12.1</avro.version>
 	</properties>
 	<parent>
 		<groupId>org.springframework.cloud</groupId>
@@ -275,11 +276,28 @@
 			<artifactId>spock-junit4</artifactId>
 			<scope>test</scope>
 		</dependency>
+		<dependency>
+			<groupId>org.spockframework</groupId>
+			<artifactId>spock-spring</artifactId>
+			<scope>test</scope>
+		</dependency>
 		<dependency>
 			<groupId>org.springframework.boot</groupId>
 			<artifactId>spring-boot-resttestclient</artifactId>
 			<scope>test</scope>
 		</dependency>
+		<dependency>
+			<groupId>org.apache.avro</groupId>
+			<artifactId>avro</artifactId>
+			<version>${avro.version}</version>
+			<scope>test</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.apache.avro</groupId>
+			<artifactId>avro</artifactId>
+			<version>${avro.version}</version>
+			<scope>provided</scope>
+		</dependency>
 	</dependencies>
 	<build>
 		<plugins>

spring-cloud-contract-verifier/src/main/java/org/springframework/cloud/contract/verifier/messaging/noop/NoOpContractVerifierAutoConfiguration.java

@@ -19,12 +19,15 @@
 import java.util.Map;
 import java.util.concurrent.TimeUnit;
 
+import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
 import org.jspecify.annotations.Nullable;
 import tools.jackson.databind.json.JsonMapper;
 
 import org.springframework.beans.factory.ObjectProvider;
 import org.springframework.boot.autoconfigure.AutoConfigureOrder;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingClass;
 import org.springframework.cloud.contract.verifier.converter.YamlContract;
 import org.springframework.cloud.contract.verifier.messaging.MessageVerifierReceiver;
 import org.springframework.cloud.contract.verifier.messaging.MessageVerifierSender;
@@ -89,12 +92,32 @@ public ContractVerifierMessaging<Object> contractVerifierMessaging() {
 
 	@Bean
 	@ConditionalOnMissingBean
-	public ContractVerifierObjectMapper contractVerifierObjectMapper(ObjectProvider<JsonMapper> jsonMapper) {
-		JsonMapper mapper = jsonMapper.getIfAvailable();
-		if (mapper != null) {
+	@ConditionalOnMissingClass("org.apache.avro.specific.SpecificRecordBase")
+	public ContractVerifierObjectMapper contractVerifierObjectMapper(
+			ObjectProvider<JsonMapper> jsonMapper) {
+		JsonMapper mapper = jsonMapper.getIfAvailable(JsonMapper::new);
+		return new ContractVerifierObjectMapper(mapper);
+	}
+
+	@Configuration(proxyBeanMethods = false)
+	@ConditionalOnClass(name = "org.apache.avro.specific.SpecificRecordBase")
+	public static class AvroContractVerifierObjectMapperConfiguration {
+
+		@Bean
+		@ConditionalOnMissingBean
+		public ContractVerifierObjectMapper avroContractVerifierObjectMapper(
+				ObjectProvider<JsonMapper> jsonMapper) throws ClassNotFoundException {
+			JsonMapper mapper = jsonMapper.getIfAvailable(JsonMapper::new).rebuild()
+					.addMixIn(
+							Class.forName("org.apache.avro.specific.SpecificRecordBase"),
+							IgnoreAvroMixin.class).build();
 			return new ContractVerifierObjectMapper(mapper);
 		}
-		return new ContractVerifierObjectMapper();
+
+		@JsonIgnoreProperties({ "schema", "specificData", "classSchema", "conversion" })
+		interface IgnoreAvroMixin {
+
+		}
 	}
 
 }

spring-cloud-contract-verifier/src/test/groovy/org/springframework/cloud/contract/verifier/messaging/internal/ContractVerifierObjectMapperAvroSpec.groovy

@@ -0,0 +1,38 @@
+/*
+ * Copyright 2013-present 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.contract.verifier.messaging.internal
+
+import org.springframework.beans.factory.annotation.Autowired
+import org.springframework.cloud.contract.verifier.messaging.noop.NoOpContractVerifierAutoConfiguration
+import org.springframework.test.context.ContextConfiguration
+import spock.lang.Specification
+
+@ContextConfiguration(classes = [NoOpContractVerifierAutoConfiguration])
+class ContractVerifierObjectMapperAvroSpec extends Specification {
+
+	@Autowired
+	ContractVerifierObjectMapper mapper
+
+	def "should convert an Avro-generated object into a json representation"() {
+		given:
+			FooAvro input = FooAvro.newBuilder().setFooAvro("barAvro").build()
+		when:
+			String result = mapper.writeValueAsString(input)
+		then:
+			result == '{"fooAvro":"barAvro"}'
+	}
+}