[Improve/rest template] RestTemplate Singleton 으로 변경

build.gradle

@@ -48,6 +48,8 @@ dependencies {
     implementation 'org.projectlombok:lombok:1.18.26'
     developmentOnly 'org.springframework.boot:spring-boot-devtools'
 
+    // http client
+    implementation 'org.apache.httpcomponents:httpclient'
     implementation 'com.google.code.gson:gson:2.10.1'
 
     // metadata config

src/main/java/com/service/core/common/resttemplate/RestTemplateService.java

@@ -10,6 +10,7 @@
 @Service
 @RequiredArgsConstructor
 public class RestTemplateService {
+    private final RestTemplate restTemplate;
 
     public String postRequestToSlack(String uri, String sender, Object data) {
         SlackPostRequest request = new SlackPostRequest(sender, data, ":love_letter:");
@@ -18,12 +19,12 @@ public String postRequestToSlack(String uri, String sender, Object data) {
     }
 
     public String getToUri(String uri) {
-        return new RestTemplate().getForObject(uri, String.class);
+        return restTemplate.getForObject(uri, String.class);
     }
 
     private String sendPost(String uri, SlackPostRequest request) {
         return String.valueOf(
-                new RestTemplate().exchange(uri, HttpMethod.POST, request.toEntity(), String.class).toString()
+                restTemplate.exchange(uri, HttpMethod.POST, request.toEntity(), String.class)
         );
     }
 }

src/main/java/com/service/core/config/web/WebConfig.java

@@ -1,11 +1,16 @@
 package com.service.core.config.web;
 
 import com.service.core.auth.presentation.AuthMemberArgumentResolver;
+
 import java.util.List;
 import lombok.RequiredArgsConstructor;
+import org.apache.http.client.HttpClient;
+import org.apache.http.impl.client.HttpClientBuilder;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
+import org.springframework.http.client.HttpComponentsClientHttpRequestFactory;
+import org.springframework.web.client.RestTemplate;
 import org.springframework.web.cors.CorsConfiguration;
 import org.springframework.web.cors.UrlBasedCorsConfigurationSource;
 import org.springframework.web.method.support.HandlerMethodArgumentResolver;
@@ -39,4 +44,18 @@ public UrlBasedCorsConfigurationSource corsConfigurationSource() {
     public void addArgumentResolvers(List<HandlerMethodArgumentResolver> resolvers) {
         resolvers.add(authMemberArgumentResolver);
     }
-}
+
+    @Bean
+    public RestTemplate buildRestTemplate(){
+        HttpComponentsClientHttpRequestFactory factory = new HttpComponentsClientHttpRequestFactory();
+        factory.setConnectTimeout(5000); // 연결시간초과, ms
+        factory.setReadTimeout(5000); // 읽기시간초과, ms
+        HttpClient httpClient = HttpClientBuilder.create()
+                .setMaxConnTotal(100) // 최대 오픈되는 커넥션 수
+                .setMaxConnPerRoute(5) // IP,포트 1쌍에 대해 수행 할 연결 수
+                .build();
+        factory.setHttpClient(httpClient);
+
+        return new RestTemplate(factory);
+    }
+}