How do you use JSON Patch with Spring Data REST?

Question

According to the Sprind Data Rest Docs it supports media type application/patch+json . Perhaps this assumption is wrong, but I take this to mean Spring Data Rest supports JSON Patch (RFC 6902) . How do you get it to work?

Here's what I've tried:

Added these dependencies to my build.gradle :

compile('org.springframework.boot:spring-boot-starter-data-rest')
compile('org.springframework.boot:spring-boot-starter-web')
compile('org.springframework.data:spring-data-keyvalue')

Using the following code:

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.data.annotation.Id;
import org.springframework.data.map.repository.config.EnableMapRepositories;
import org.springframework.data.repository.CrudRepository;
import org.springframework.data.repository.query.Param;
import org.springframework.data.rest.core.annotation.RepositoryRestResource;
import org.springframework.data.rest.core.annotation.RestResource;
import org.springframework.stereotype.Component;

import java.util.List;
import java.util.UUID;

@SpringBootApplication
@EnableMapRepositories
public class SpringDataRest1Application {
  public static void main(String[] args) {
    SpringApplication.run(SpringDataRest1Application.class, args);
  }
}

@RepositoryRestResource
interface UserRepository extends CrudRepository<User, UUID> {

  @RestResource(path = "by-name")
  List<User> findByName(@Param("name") String name);

}


class User {

  @Id
  private UUID id = UUID.randomUUID();
  private String name;
  private int age;


  public User() {
  }

  public User(String name, int age) {
    this.name = name;
    this.age = age;
  }

  public String getName() {
    return name;
  }

  public void setName(String name) {
    this.name = name;
  }

  public User(UUID id) {
    this.id = id;
  }

  public int getAge() {
    return age;
  }

  public void setAge(int age) {
    this.age = age;
  }

  public UUID getId() {
    return id;
  }

  @Override
  public String toString() {
    final StringBuilder sb = new StringBuilder("User{");
    sb.append("id=").append(id);
    sb.append(", name='").append(name).append('\'');
    sb.append(", age=").append(age);
    sb.append('}');
    return sb.toString();
  }

}

@Component
class SampleDataCLR implements CommandLineRunner {

  private UserRepository userRepository;

  @Autowired
  public SampleDataCLR(UserRepository userRepository) {
    this.userRepository = userRepository;
  }

  @Override
  public void run(String... args) throws Exception {
    userRepository.save(new User("Ethan", 10));
    userRepository.findAll().forEach(System.out::println);
  }
}

To show it's working after running the above:

$ curl http://localhost:8080/users/55967eb0-d76e-4e62-9313-fe35d7cfa193
{
  "name" : "Ethan",
  "age" : 10,
  "_links" : {
    "self" : {
      "href" : "http://localhost:8080/users/55967eb0-d76e-4e62-9313-fe35d7cfa193"
    },
    "user" : {
      "href" : "http://localhost:8080/users/55967eb0-d76e-4e62-9313-fe35d7cfa193"
    }
  }
}

When I attempt this call, which I believe conforms to JSON Patch :

curl --request PATCH localhost:8080/users/55967eb0-d76e-4e62-9313-fe35d7cfa193 --data '[{ "op": "replace", "path": "/age", "value": "15" }]' -H "Content-Type: application/patch+json"

I get this error:

{"cause":{"cause":null,"message":"com.fasterxml.jackson.databind.node.ArrayNode cannot be cast to com.fasterxml.jackson.databind.node.ObjectNode"},"message":"Could not read payload!; nested exception is java.lang.ClassCastException: com.fasterxml.jackson.databind.node.ArrayNode cannot be cast to com.fasterxml.jackson.databind.node.ObjectNode"}

The logs show:

2017-03-08 13:30:59.869 ERROR 6852 --- [nio-8080-exec-2] o.s.d.r.w.RepositoryRestExceptionHandler : Could not read payload!; nested exception is java.lang.ClassCastException: com.fasterxml.jackson.databind.node.ArrayNode cannot be cast to com.fasterxml.jackson.databind.node.ObjectNode

org.springframework.http.converter.HttpMessageNotReadableException: Could not read payload!; nested exception is java.lang.ClassCastException: com.fasterxml.jackson.databind.node.ArrayNode cannot be cast to com.fasterxml.jackson.databind.node.ObjectNode
    at org.springframework.data.rest.webmvc.json.DomainObjectReader.read(DomainObjectReader.java:89) ~[spring-data-rest-webmvc-2.6.1.RELEASE.jar:na]
    at org.springframework.data.rest.webmvc.config.JsonPatchHandler.applyMergePatch(JsonPatchHandler.java:95) ~[spring-data-rest-webmvc-2.6.1.RELEASE.jar:na]
    at org.springframework.data.rest.webmvc.config.JsonPatchHandler.apply(JsonPatchHandler.java:85) ~[spring-data-rest-webmvc-2.6.1.RELEASE.jar:na]
    at org.springframework.data.rest.webmvc.config.PersistentEntityResourceHandlerMethodArgumentResolver.readPatch(PersistentEntityResourceHandlerMethodArgumentResolver.java:198) ~[spring-data-rest-webmvc-2.6.1.RELEASE.jar:na]
    at org.springframework.data.rest.webmvc.config.PersistentEntityResourceHandlerMethodArgumentResolver.read(PersistentEntityResourceHandlerMethodArgumentResolver.java:176) ~[spring-data-rest-webmvc-2.6.1.RELEASE.jar:na]
    at org.springframework.data.rest.webmvc.config.PersistentEntityResourceHandlerMethodArgumentResolver.resolveArgument(PersistentEntityResourceHandlerMethodArgumentResolver.java:138) ~[spring-data-rest-webmvc-2.6.1.RELEASE.jar:na]
    at org.springframework.web.method.support.HandlerMethodArgumentResolverComposite.resolveArgument(HandlerMethodArgumentResolverComposite.java:121) ~[spring-web-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.web.method.support.InvocableHandlerMethod.getMethodArgumentValues(InvocableHandlerMethod.java:158) ~[spring-web-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:128) ~[spring-web-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:116) ~[spring-webmvc-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:827) ~[spring-webmvc-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:738) ~[spring-webmvc-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85) ~[spring-webmvc-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:963) ~[spring-webmvc-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:897) ~[spring-webmvc-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970) ~[spring-webmvc-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:843) ~[spring-webmvc-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:729) ~[tomcat-embed-core-8.5.11.jar:8.5.11]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:230) [tomcat-embed-core-8.5.11.jar:8.5.11]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.11.jar:8.5.11]
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) [tomcat-embed-websocket-8.5.11.jar:8.5.11]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.11.jar:8.5.11]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.11.jar:8.5.11]
    at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99) [spring-web-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.11.jar:8.5.11]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.11.jar:8.5.11]
    at org.springframework.web.filter.HttpPutFormContentFilter.doFilterInternal(HttpPutFormContentFilter.java:105) [spring-web-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.11.jar:8.5.11]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.11.jar:8.5.11]
    at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:81) [spring-web-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.11.jar:8.5.11]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.11.jar:8.5.11]
    at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:197) [spring-web-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) [tomcat-embed-core-8.5.11.jar:8.5.11]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) [tomcat-embed-core-8.5.11.jar:8.5.11]
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198) [tomcat-embed-core-8.5.11.jar:8.5.11]
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) [tomcat-embed-core-8.5.11.jar:8.5.11]
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:474) [tomcat-embed-core-8.5.11.jar:8.5.11]
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140) [tomcat-embed-core-8.5.11.jar:8.5.11]
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79) [tomcat-embed-core-8.5.11.jar:8.5.11]
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87) [tomcat-embed-core-8.5.11.jar:8.5.11]
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:349) [tomcat-embed-core-8.5.11.jar:8.5.11]
    at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:783) [tomcat-embed-core-8.5.11.jar:8.5.11]
    at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) [tomcat-embed-core-8.5.11.jar:8.5.11]
    at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:798) [tomcat-embed-core-8.5.11.jar:8.5.11]
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1434) [tomcat-embed-core-8.5.11.jar:8.5.11]
    at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-embed-core-8.5.11.jar:8.5.11]
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [na:1.8.0_121]
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [na:1.8.0_121]
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-8.5.11.jar:8.5.11]
    at java.lang.Thread.run(Thread.java:745) [na:1.8.0_121]
Caused by: java.lang.ClassCastException: com.fasterxml.jackson.databind.node.ArrayNode cannot be cast to com.fasterxml.jackson.databind.node.ObjectNode
    at org.springframework.data.rest.webmvc.json.DomainObjectReader.read(DomainObjectReader.java:87) ~[spring-data-rest-webmvc-2.6.1.RELEASE.jar:na]
    ... 54 common frames omitted

Answer 1

According to following source code your request is not considered as JSON PATCH: https://github.com/spring-projects/spring-data-rest/blob/master/spring-data-rest-webmvc/src/main/java/org/springframework/data/rest/webmvc/RestMediaTypes.java

You have to use "Content-Type: application/json-patch+json"