RestTemplate is commonly used for external API call in Spring.
But from Spring 5, WebClient in WebFlux is preferred over RestTemplate.
First, add this dependency to build.gradle.
// build.gradle
// ...
implementation 'org.springframework.boot:spring-boot-starter-webflux'
// ...
Then create a bean to inject into different classes.
package com.litsynp.application.domain.global.config;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.reactive.function.client.WebClient;
@Configuration
public class WebClientConfig {
@Bean
public WebClient.Builder getWebClientBuilder() {
return WebClient.builder();
}
}
Finally, inject WebClientBuilder into the service and build the web client to call the external API.
import org.springframework.http.ResponseEntity;
import org.springframework.stereotype.Service;
import org.springframework.web.reactive.function.client.WebClient;
@Service
@RequiredArgsConstructor
public class ExterrnalApiService {
private final WebClient.Builder webClientBuilder;
public ResponseEntity<?> get() {
return webClientBuilder.baseUrl("https://randomuser.me").build()
.get()
.uri("/api")
.retrieve()
.toEntity(Object.class) // Response DTO Type
.block();
}
public ResponseEntity<?> create() {
return webClientBuilder.baseUrl("https://gorest.co.in").build()
.post()
.uri("/public/v2/users")
.header("Authorization", "Bearer AAA.BBB.CCC")
.header("Content-Type", "application/json")
.bodyValue(new HashMap<String, Object>() {{
put("email", "abdasdfc@tesat.com");
put("name", "abc");
put("gender", "male");
put("status", "active");
}})
.retrieve()
.toEntity(Object.class)
.block();
}
}
* Used https://randomuser.me and https://gorest.co.in for external API testing.
REF
https://stackoverflow.com/questions/42365266/call-another-rest-api-from-my-server-in-spring-boot