Spring RestTemplate

Spring RestClient

public class Foo implements Serializable {

    private long id;

 

    private String name;

    // standard getters and setters

}

// Request Factory

ClientHttpRequestFactory requestFactory = getClientHttpRequestFactory();

RestTemplate restTemplate = new RestTemplate(requestFactory);

private ClientHttpRequestFactory getClientHttpRequestFactory() {

    int timeout = 5000;

    HttpComponentsClientHttpRequestFactory clientHttpRequestFactory

      = new HttpComponentsClientHttpRequestFactory();

    clientHttpRequestFactory.setConnectTimeout(timeout);

    return clientHttpRequestFactory;

}

// GET Method

Foo foo = restTemplate

  .getForObject(fooResourceUrl + "/1", Foo.class);

// POST Method

HttpEntity<Foo> request = new HttpEntity<>(new Foo("bar"));

Foo foo = restTemplate.postForObject(fooResourceUrl, request, Foo.class);

RequestFactory With HttpClient

private ClientHttpRequestFactory getClientHttpRequestFactory() {

    int timeout = 5000;

    RequestConfig config = RequestConfig.custom()

      .setConnectTimeout(timeout)

      .setConnectionRequestTimeout(timeout)

      .setSocketTimeout(timeout)

      .build();

    CloseableHttpClient client = HttpClientBuilder

      .create()

      .setDefaultRequestConfig(config)

      .build();

    return new HttpComponentsClientHttpRequestFactory(client);

}

그외의 것들

• RestTemplate 객체는 무거운 객체이다. 한번 생성한 객체를 다시 사용하자
• 기본적으로 RestTemplate를 connection pool를 관리를 하지 않는다. 요청할때마다 connection을 만드는 구조이기 때문에 tcp connection이 증가가 할수 있다
• connection pool 도입하는 방법을 HttpClient를 이용하여 Reqeust Factory를 생성을 하면 된다.

HttpComponentsClientHttpRequestFactory httpRequestFactory = new HttpComponentsClientHttpRequestFactory();

httpRequestFactory.setConnectTimeout(xxx);

httpRequestFactory.setReadTimeout(xxx);

HttpClient httpClient = HttpClientBuilder.create()

 .setMaxConnTotal(xxx)

 .setMaxConnPerRoute(xxx)

 .build();

httpRequestFactory.setHttpClient(httpClient);

RestTemplate restTemplate = new RestTemplate(httpRequestFactory);

Reference

• http://www.baeldung.com/rest-template