Unable to find a MessageBodyReader - RestEasy / Quarkus

Question

I don't know what to do to fix it. When accessing localhost:8080/pets/findByStatusLocal is returning the following error.

Error

Error id 9175b683-f00f-4a8d-9246-a30eb0f8865f-5, javax.ws.rs.ProcessingException: RESTEASY003145: Unable to find a MessageBodyReader of content-type application/json and type interface java.util.List

Pet.java

package org.test;

public class Pet {

    private Long id;
    private String name;

    public Pet() {
        this(null, null);
    }

    public Pet(Long id, String name) {
        this.id = id;
        this.name = name;
    }

    
    public Long getId() {
        return id;
    }

    public void setId(Long id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

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

application.properties

org.test.PetService/mp-rest/url=https://petstore.swagger.io/v2/
org.test.PetService/mp-rest/scope=javax.inject.Singleton

PetService.java

package org.test;
import java.util.List;
import java.util.concurrent.CompletionStage;

import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import javax.ws.rs.QueryParam;
import javax.ws.rs.core.MediaType;

import org.eclipse.microprofile.rest.client.inject.RegisterRestClient;

@Path("/pet")
@RegisterRestClient
public interface PetService {

    @GET
    @Produces(MediaType.APPLICATION_JSON)
    @Path("findByStatus")
    public List<Pet> findByStatus(@QueryParam("status") String status);

    @GET
    @Produces(MediaType.APPLICATION_JSON)
    @Path("findByStatus")
  
  public CompletionStage<List<Pet>> findByStatusAsync(@QueryParam("status") String status);
}

PetResource.java

package org.test;

import java.util.List;
import java.util.concurrent.CompletionStage;

import javax.inject.Inject;
import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import javax.ws.rs.QueryParam;
import javax.ws.rs.core.MediaType;

import org.eclipse.microprofile.rest.client.inject.RestClient;

@Path("/pets")
public class PetResource {

    @Inject
    @RestClient
    PetService petService;

    @GET
    @Produces(MediaType.APPLICATION_JSON)
    @Path("findByStatusLocal")
    public List<Pet> methodname(@QueryParam("status") String status) {
        return petService.findByStatus(status);
    }

    @GET
    @Produces(MediaType.APPLICATION_JSON)
    @Path("findByStatusLocalAsync")
    public CompletionStage<List<Pet>> async(@QueryParam("status") String status) {
        return petService.findByStatusAsync(status);
    }
    
}

Is it an error in the source code or could it be in the project configuration? Thank you very much

*** I made the correction - pom.xml:

  <dependency>
      <groupId>io.quarkus</groupId>
      <artifactId>quarkus-resteasy</artifactId>
    </dependency>
    <dependency>
      <groupId>io.quarkus</groupId>
      <artifactId>quarkus-resteasy-jackson</artifactId>
    </dependency>
    <dependency>
      <groupId>io.quarkus</groupId>
      <artifactId>quarkus-rest-client-jackson</artifactId>
    </dependency>
    <dependency>
      <groupId>io.quarkus</groupId>
      <artifactId>quarkus-rest-client</artifactId>
    </dependency>

Answer 1

You need the quarkus-resteasy-reactive-jackson to write (and read) JSON object. Alternatively, you can also use the -jsonb extension. However, I highly recommend Jackson in this case as it offers many more features.

So, in your pom.xml file, add:

<dependency>
  <groupId>io.quarkus</groupId>
  <artifactId>quarkus-resteasy-reactive-jackson</artifactId>
</dependency>