스페이스 당 하나의 그래프만 생성되도록 오류 수정 -> db에 unique 제약 조건 (조회 시 그래프가 없는 경우는 새 그…

src/main/java/com/example/gp_backend_data/graph/domain/entity/Graph.java

@@ -12,7 +12,9 @@
 @NoArgsConstructor
 @AllArgsConstructor
 @Builder
-@Table(name = "Graph", schema = "gp_data")
+@Table(name = "Graph", schema = "gp_data", uniqueConstraints = {
+        @UniqueConstraint(columnNames = "space_id")
+})
 public class Graph {
 
     @Id

src/main/java/com/example/gp_backend_data/graph/service/GraphService.java

@@ -7,6 +7,7 @@
 import com.example.gp_backend_data.utils.UUIDHelper;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import lombok.RequiredArgsConstructor;
+import org.springframework.dao.DataIntegrityViolationException;
 import org.springframework.stereotype.Service;
 import org.springframework.transaction.annotation.Transactional;
 
@@ -22,22 +23,42 @@ public class GraphService {
     private final UUIDHelper uuidHelper;
 
     //특정 스페이스의 그래프 조회
+    @Transactional
     public GraphResponse getGraphBySpaceId(UUID spaceId) {
-        Optional<Graph> graphOptional = graphRepository.findBySpaceId(uuidHelper.convertUUIDToByteArray(spaceId));
+        byte[] spaceIdBytes = uuidHelper.convertUUIDToByteArray(spaceId);
 
-        return graphOptional.map(graph -> {
-            try {
-                return new GraphResponse(
-                        uuidHelper.convertByteArrayToUUID(graph.getGraphId()),
-                        uuidHelper.convertByteArrayToUUID(graph.getSpaceId()),
-                        objectMapper.readTree(graph.getData())
-                );
-            } catch (Exception e) {
-                throw new RuntimeException("Error parsing graph data", e);
-            }
-        }).orElseThrow(() -> new IllegalArgumentException("Graph not found for spaceId: " + spaceId));
+        Graph graph = graphRepository.findBySpaceId(spaceIdBytes)
+                .orElseGet(() -> createNewGraphForSpace(spaceIdBytes));
+
+        try {
+            return new GraphResponse(
+                    uuidHelper.convertByteArrayToUUID(graph.getGraphId()),
+                    uuidHelper.convertByteArrayToUUID(graph.getSpaceId()),
+                    objectMapper.readTree(graph.getData())
+            );
+        } catch (Exception e) {
+            throw new RuntimeException("Error parsing graph data", e);
+        }
     }
 
+    private Graph createNewGraphForSpace(byte[] spaceIdBytes) {
+        try {
+            UUID newGraphId = UUID.randomUUID();
+
+            Graph graph = new Graph();
+            graph.setGraphId(uuidHelper.convertUUIDToByteArray(newGraphId));
+            graph.setSpaceId(spaceIdBytes);
+            graph.setData("{}"); // 또는 AI summary 생성 로직
+
+            return graphRepository.save(graph);
+        } catch (DataIntegrityViolationException e) {
+            // 동시성 문제로 인한 중복 생성 방지
+            return graphRepository.findBySpaceId(spaceIdBytes)
+                    .orElseThrow(() -> new IllegalStateException("Graph creation failed due to race condition"));
+        }
+    }
+
+
     //그래프 세부 정보 조회
     public GraphResponse getGraphById(UUID graphId) {
         Optional<Graph> graphOptional = graphRepository.findByGraphId(uuidHelper.convertUUIDToByteArray(graphId));