[BACKEND] feat: PC 호환성 체크 API 및 실시간 SSE 스트리밍 구현 (#108)

- 비동기 스레드 풀 구현에 잘못된 점이 있어 리팩토링 예정

Author: oxomi

backend/build.gradle

@@ -47,6 +47,7 @@ dependencies {
 
 	implementation 'org.springframework.boot:spring-boot-starter-data-elasticsearch'
 
+	implementation 'com.google.genai:google-genai:1.8.0'
 	implementation 'software.amazon.awssdk:s3:2.25.27'
 }
 

backend/src/main/java/com/cmg/comtogether/common/config/AsyncConfig.java

@@ -0,0 +1,25 @@
+package com.cmg.comtogether.common.config;
+
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.scheduling.annotation.EnableAsync;
+import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;
+
+import java.util.concurrent.Executor;
+
+@Configuration
+@EnableAsync
+public class AsyncConfig {
+
+    @Bean(name = "compatibilityCheckExecutor")
+    public Executor compatibilityCheckExecutor() {
+        ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
+        executor.setCorePoolSize(10);
+        executor.setMaxPoolSize(20);
+        executor.setQueueCapacity(100);
+        executor.setThreadNamePrefix("compatibility-check-");
+        executor.initialize();
+        return executor;
+    }
+}
+

backend/src/main/java/com/cmg/comtogether/common/exception/ErrorCode.java

@@ -29,6 +29,10 @@ public enum ErrorCode {
 
     // 네이버 상품 API
     NAVER_API_ERROR(502, "NAVER-999", "네이버 서버와 통신 중 오류가 발생했습니다."),
+    
+    // Gemini API
+    GEMINI_API_ERROR(502, "GEMINI-999", "Gemini API와 통신 중 오류가 발생했습니다."),
+    
 
     // 가이드
     GUIDE_NOT_FOUND(404, "GUIDE-001", "가이드를 찾을 수 없습니다"),

backend/src/main/java/com/cmg/comtogether/common/security/config/SecurityConfig.java

@@ -39,7 +39,9 @@ public SecurityFilterChain securityFilterChain(HttpSecurity http, CorsConfigurat
                                 "/refresh/**",
                                 "/swagger-ui/**",
                                 "/v3/api-docs/**",
-                                "/users/login"
+                                "/users/login",
+                                "/compatibility/**",
+                                "/gemini/**"
                         ).permitAll()
                         .requestMatchers(
                                 "/users/all",

backend/src/main/java/com/cmg/comtogether/compatibility/controller/CompatibilityController.java

@@ -0,0 +1,105 @@
+package com.cmg.comtogether.compatibility.controller;
+
+import com.cmg.comtogether.compatibility.dto.CompatibilityCheckRequestDto;
+import com.cmg.comtogether.compatibility.service.CompatibilityCheckService;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import jakarta.validation.Valid;
+import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.http.MediaType;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+import org.springframework.web.servlet.mvc.method.annotation.SseEmitter;
+
+import java.io.IOException;
+import java.util.concurrent.CompletableFuture;
+
+@Slf4j
+@RestController
+@RequestMapping("/compatibility")
+@RequiredArgsConstructor
+public class CompatibilityController {
+
+    private final CompatibilityCheckService compatibilityCheckService;
+    private final ObjectMapper objectMapper;
+
+    /**
+     * 호환성 체크 (SSE 스트리밍)
+     * 각 검사 항목이 완료되는 대로 실시간으로 결과를 전송
+     */
+    @PostMapping(value = "/check", produces = MediaType.TEXT_EVENT_STREAM_VALUE)
+    public ResponseEntity<SseEmitter> checkCompatibility(
+            @Valid @RequestBody CompatibilityCheckRequestDto requestDto
+    ) {
+        SseEmitter emitter = new SseEmitter(300000L); // 5분 타임아웃
+
+        // 초기 연결 확인
+        try {
+            emitter.send(SseEmitter.event()
+                    .name("connected")
+                    .data("호환성 체크를 시작합니다."));
+        } catch (IOException e) {
+            log.error("SSE 초기 연결 실패", e);
+            emitter.completeWithError(e);
+            return ResponseEntity.ok(emitter);
+        }
+
+        // 비동기로 호환성 체크 실행
+        CompletableFuture.runAsync(() -> {
+            try {
+                compatibilityCheckService.checkCompatibility(
+                        requestDto.getItems(),
+                        result -> {
+                            try {
+                                // JSON을 포맷팅하여 가독성 향상
+                                String formattedJson = objectMapper.writerWithDefaultPrettyPrinter()
+                                        .writeValueAsString(result);
+                                
+                                // 각 검사 항목 완료 시 SSE로 전송 (포맷팅된 JSON 사용)
+                                emitter.send(SseEmitter.event()
+                                        .name("result")
+                                        .data(formattedJson));
+                            } catch (IOException e) {
+                                log.error("SSE 전송 실패", e);
+                                emitter.completeWithError(e);
+                            }
+                        }
+                ).join();
+
+                // 모든 검사 완료
+                emitter.send(SseEmitter.event()
+                        .name("completed")
+                        .data("모든 호환성 검사가 완료되었습니다."));
+                emitter.complete();
+
+            } catch (Exception e) {
+                log.error("호환성 체크 중 오류 발생", e);
+                try {
+                    emitter.send(SseEmitter.event()
+                            .name("error")
+                            .data("호환성 체크 중 오류가 발생했습니다: " + e.getMessage()));
+                } catch (IOException ioException) {
+                    log.error("에러 메시지 전송 실패", ioException);
+                }
+                emitter.completeWithError(e);
+            }
+        });
+
+        // 연결 종료 시 처리
+        emitter.onCompletion(() -> log.debug("SSE 연결 완료"));
+        emitter.onTimeout(() -> {
+            log.warn("SSE 연결 타임아웃");
+            emitter.complete();
+        });
+        emitter.onError((ex) -> {
+            log.error("SSE 연결 오류", ex);
+            emitter.completeWithError(ex);
+        });
+
+        return ResponseEntity.ok(emitter);
+    }
+}
+

backend/src/main/java/com/cmg/comtogether/compatibility/dto/CompatibilityCheckRequestDto.java

@@ -0,0 +1,18 @@
+package com.cmg.comtogether.compatibility.dto;
+
+import jakarta.validation.constraints.NotEmpty;
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+import java.util.List;
+
+@Getter
+@NoArgsConstructor
+@AllArgsConstructor
+public class CompatibilityCheckRequestDto {
+
+    @NotEmpty(message = "견적 아이템 목록은 필수입니다.")
+    private List<CompatibilityItemDto> items;
+}
+

backend/src/main/java/com/cmg/comtogether/compatibility/dto/CompatibilityCheckResultDto.java

@@ -0,0 +1,34 @@
+package com.cmg.comtogether.compatibility.dto;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+import lombok.AllArgsConstructor;
+import lombok.Builder;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+import java.util.List;
+
+@Getter
+@Builder
+@NoArgsConstructor
+@AllArgsConstructor
+public class CompatibilityCheckResultDto {
+
+    @JsonProperty("check_id")
+    private Integer checkId; // 1~10
+
+    @JsonProperty("check_name")
+    private String checkName; // 예: "CPU ↔ 메인보드 호환성"
+
+    private String result; // "POSITIVE", "NEGATIVE", "UNKNOWN"
+
+    private List<String> errors;
+
+    private List<String> warnings;
+
+    private String details;
+
+    @JsonProperty("status")
+    private String status; // "PENDING", "COMPLETED", "ERROR"
+}
+

backend/src/main/java/com/cmg/comtogether/compatibility/dto/CompatibilityItemDto.java

@@ -0,0 +1,22 @@
+package com.cmg.comtogether.compatibility.dto;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+import jakarta.validation.constraints.NotBlank;
+import lombok.AllArgsConstructor;
+import lombok.Builder;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+@Getter
+@Builder
+@NoArgsConstructor
+@AllArgsConstructor
+public class CompatibilityItemDto {
+
+    @NotBlank(message = "제품명은 필수입니다.")
+    private String title;
+
+    @JsonProperty("category3")
+    private String category3; // 카테고리 (예: CPU, 메인보드, RAM 등)
+}
+