Archivo del skill

Restclient Migration

Name: Restclient Migration
Author: benchflow-ai

Migrate RestTemplate to RestClient in Spring Boot 3.2+. Use when replacing deprecated RestTemplate with modern fluent API, updating HTTP client code, or configuring RestClient beans. Covers GET/POST/DELETE migrations, error handling, and ParameterizedTypeReference usage.

benchflow-ai990 estrellas22 ene 2026

Ocupación
Categorías: Herramientas de Bases de Datos

Contenido de la habilidad

RestTemplate to RestClient Migration Skill

Overview

Spring Framework 6.1 (Spring Boot 3.2+) introduces RestClient, a modern, fluent API for synchronous HTTP requests that replaces the older RestTemplate. While RestTemplate still works, RestClient is the recommended approach for new code.

Key Differences

Feature	RestTemplate	RestClient
API Style	Template methods	Fluent builder
Configuration	Constructor injection	Builder pattern
Error handling	ResponseErrorHandler	Status handlers
Type safety	Limited	Better with generics

Migration Examples

Skills relacionados

Restclient Migration | Skills Pool

@Service
public class ExternalApiService {
    private final RestTemplate restTemplate;

    public ExternalApiService() {
        this.restTemplate = new RestTemplate();
    }

    public Map<String, Object> getUser(String userId) {
        String url = "https://api.example.com/users/" + userId;
        ResponseEntity<Map> response = restTemplate.getForEntity(url, Map.class);
        return response.getBody();
    }
}

@Service
public class ExternalApiService {
    private final RestClient restClient;

    public ExternalApiService() {
        this.restClient = RestClient.create();
    }

    public Map<String, Object> getUser(String userId) {
        return restClient.get()
            .uri("https://api.example.com/users/{id}", userId)
            .retrieve()
            .body(new ParameterizedTypeReference<Map<String, Object>>() {});
    }
}

public void sendNotification(String userId, String message) {
    String url = baseUrl + "/notifications";

    HttpHeaders headers = new HttpHeaders();
    headers.setContentType(MediaType.APPLICATION_JSON);
    headers.setAccept(Collections.singletonList(MediaType.APPLICATION_JSON));

    Map<String, String> payload = Map.of(
        "userId", userId,
        "message", message
    );

    HttpEntity<Map<String, String>> request = new HttpEntity<>(payload, headers);
    restTemplate.postForEntity(url, request, Void.class);
}

public void sendNotification(String userId, String message) {
    Map<String, String> payload = Map.of(
        "userId", userId,
        "message", message
    );

    restClient.post()
        .uri(baseUrl + "/notifications")
        .contentType(MediaType.APPLICATION_JSON)
        .accept(MediaType.APPLICATION_JSON)
        .body(payload)
        .retrieve()
        .toBodilessEntity();
}

public Map<String, Object> enrichUserProfile(String userId) {
    String url = baseUrl + "/users/" + userId + "/profile";

    HttpHeaders headers = new HttpHeaders();
    headers.setAccept(Collections.singletonList(MediaType.APPLICATION_JSON));

    HttpEntity<?> request = new HttpEntity<>(headers);

    ResponseEntity<Map> response = restTemplate.exchange(
        url,
        HttpMethod.GET,
        request,
        Map.class
    );

    return response.getBody();
}

public Map<String, Object> enrichUserProfile(String userId) {
    return restClient.get()
        .uri(baseUrl + "/users/{id}/profile", userId)
        .accept(MediaType.APPLICATION_JSON)
        .retrieve()
        .body(new ParameterizedTypeReference<Map<String, Object>>() {});
}

public boolean requestDataDeletion(String userId) {
    try {
        String url = baseUrl + "/users/" + userId + "/data";
        restTemplate.delete(url);
        return true;
    } catch (Exception e) {
        return false;
    }
}

public boolean requestDataDeletion(String userId) {
    try {
        restClient.delete()
            .uri(baseUrl + "/users/{id}/data", userId)
            .retrieve()
            .toBodilessEntity();
        return true;
    } catch (Exception e) {
        return false;
    }
}

@Configuration
public class RestClientConfig {

    @Value("${external.api.base-url}")
    private String baseUrl;

    @Bean
    public RestClient restClient() {
        return RestClient.builder()
            .baseUrl(baseUrl)
            .defaultHeader(HttpHeaders.CONTENT_TYPE, MediaType.APPLICATION_JSON_VALUE)
            .defaultHeader(HttpHeaders.ACCEPT, MediaType.APPLICATION_JSON_VALUE)
            .build();
    }
}

@Service
public class ExternalApiService {
    private final RestClient restClient;

    public ExternalApiService(RestClient restClient) {
        this.restClient = restClient;
    }

    // Methods can now use relative URIs
    public Map<String, Object> getUser(String userId) {
        return restClient.get()
            .uri("/users/{id}", userId)
            .retrieve()
            .body(new ParameterizedTypeReference<Map<String, Object>>() {});
    }
}

public Map<String, Object> getUserWithErrorHandling(String userId) {
    return restClient.get()
        .uri("/users/{id}", userId)
        .retrieve()
        .onStatus(HttpStatusCode::is4xxClientError, (request, response) -> {
            throw new UserNotFoundException("User not found: " + userId);
        })
        .onStatus(HttpStatusCode::is5xxServerError, (request, response) -> {
            throw new ExternalServiceException("External service error");
        })
        .body(new ParameterizedTypeReference<Map<String, Object>>() {});
}

// For generic types like Map or List
Map<String, Object> map = restClient.get()
    .uri("/data")
    .retrieve()
    .body(new ParameterizedTypeReference<Map<String, Object>>() {});

List<User> users = restClient.get()
    .uri("/users")
    .retrieve()
    .body(new ParameterizedTypeReference<List<User>>() {});

// For simple types
User user = restClient.get()
    .uri("/users/{id}", userId)
    .retrieve()
    .body(User.class);

String text = restClient.get()
    .uri("/text")
    .retrieve()
    .body(String.class);

@Service
public class ExternalApiService {
    private final RestTemplate restTemplate;

    @Value("${external.api.base-url}")
    private String baseUrl;

    public ExternalApiService() {
        this.restTemplate = new RestTemplate();
    }

    public boolean verifyEmail(String email) {
        try {
            String url = baseUrl + "/verify/email?email=" + email;
            ResponseEntity<Map> response = restTemplate.getForEntity(url, Map.class);
            return Boolean.TRUE.equals(response.getBody().get("valid"));
        } catch (Exception e) {
            return false;
        }
    }
}

@Service
public class ExternalApiService {
    private final RestClient restClient;

    @Value("${external.api.base-url}")
    private String baseUrl;

    public ExternalApiService() {
        this.restClient = RestClient.create();
    }

    public boolean verifyEmail(String email) {
        try {
            Map<String, Object> response = restClient.get()
                .uri(baseUrl + "/verify/email?email={email}", email)
                .retrieve()
                .body(new ParameterizedTypeReference<Map<String, Object>>() {});
            return response != null && Boolean.TRUE.equals(response.get("valid"));
        } catch (Exception e) {
            return false;
        }
    }
}

// WebClient for reactive/async operations
WebClient webClient = WebClient.create(baseUrl);

Mono<User> userMono = webClient.get()
    .uri("/users/{id}", userId)
    .retrieve()
    .bodyToMono(User.class);

Restclient Migration

RestTemplate to RestClient Migration Skill

Overview

Key Differences

Migration Examples

Restclient Migration

RestTemplate to RestClient Migration Skill

Overview

Key Differences

Migration Examples

1. Basic GET Request

Before (RestTemplate)

After (RestClient)

2. POST Request with Body

Before (RestTemplate)

After (RestClient)

3. Exchange with Custom Headers

Before (RestTemplate)

After (RestClient)

4. DELETE Request

Before (RestTemplate)

After (RestClient)

RestClient Configuration

Creating a Configured RestClient

Using the Configured RestClient

Error Handling

RestClient Status Handlers

Type-Safe Responses

Using ParameterizedTypeReference

Direct Class Mapping

Complete Service Migration Example

Before

After

WebClient Alternative

Database Migrations

Database Migrations

Postgres Patterns

Frontend Query & Mutation

Db Migrations

Drizzle