길찾기 로직 업데이트

backend/build.gradle

@@ -62,6 +62,10 @@ dependencies {
 	// OpenCSV
 	implementation 'com.opencsv:opencsv:5.7.1'
 
+	// Cache
+	implementation 'org.springframework.boot:spring-boot-starter-cache'
+	implementation 'com.github.ben-manes.caffeine:caffeine'
+
 	// Servlet API
 	//compileOnly 'jakarta.servlet:jakarta.servlet-api:6.0.0'
 
@@ -74,6 +78,9 @@ dependencies {
 	testImplementation 'org.testcontainers:junit-jupiter' // 어노테이션 담당
 	testImplementation 'org.testcontainers:postgresql'
 	testRuntimeOnly 'org.junit.platform:junit-platform-launcher'
+
+	// GraphHopper
+	implementation 'com.graphhopper:graphhopper-core:9.0'
 }
 
 tasks.named('test') {

backend/src/main/java/_team/onmyway/service/ImageService.java

@@ -3,6 +3,8 @@
 import _team.onmyway.entity.Photos;
 import _team.onmyway.entity.Place;
 import _team.onmyway.repository.PhotosRepository;
+import com.github.benmanes.caffeine.cache.Cache;
+import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
 import org.springframework.stereotype.Service;
 import org.springframework.web.reactive.function.client.WebClient;
@@ -18,15 +20,17 @@ public class ImageService {
 
     private final WebClient webClient;
     private final PhotosRepository photosRepository;
+    private final Cache<Long, String> placePhotoCache;
 
     @Value("${naver.api.clientId}")
     private String naverClientId;
 
     @Value("${naver.api.clientSecret}")
     private String naverClientSecret;
 
-    public ImageService(PhotosRepository photosRepository) {
+    public ImageService(PhotosRepository photosRepository, Cache<Long, String> placePhotoCache) {
         this.photosRepository = photosRepository;
+        this.placePhotoCache = placePhotoCache;
         this.webClient = WebClient.builder()
                 .baseUrl("https://openapi.naver.com")
                 .build();
@@ -37,8 +41,14 @@ public Mono<String> getImageURL(Place p) {
         if (hasPhoto) {
             return Mono.just(photosRepository.findFirstByPlaceId(p.getId()).get().getPhotoURL());
         } else {
-            String distinct = p.getAddress().split(" ")[2];
+            String cacheURL = placePhotoCache.getIfPresent(p.getId());
+            if (cacheURL != null) {
+                return Mono.just(cacheURL);
+            }
+
+            String distinct = p.getAddress();
             String name = p.getName();
+
             return webClient.get()
                     .uri(uri -> uri
                             .path("/v1/search/image")

backend/src/main/java/_team/onmyway/service/RouteService.java

@@ -4,8 +4,17 @@
 import _team.onmyway.dto.RouteResponseDTO;
 import com.fasterxml.jackson.databind.JsonNode;
 import com.fasterxml.jackson.databind.ObjectMapper;
+import com.graphhopper.GraphHopper;
+import com.graphhopper.routing.util.EdgeFilter;
+import com.graphhopper.storage.BaseGraph;
+import com.graphhopper.storage.NodeAccess;
+import com.graphhopper.storage.index.LocationIndex;
+import com.graphhopper.storage.index.Snap;
+import com.graphhopper.util.EdgeExplorer;
+import com.graphhopper.util.shapes.GHPoint;
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
+import org.locationtech.jts.edgegraph.EdgeGraph;
 import org.springframework.beans.factory.annotation.Qualifier;
 import org.springframework.beans.factory.annotation.Value;
 import org.springframework.http.HttpHeaders;
@@ -19,15 +28,15 @@
 import reactor.core.publisher.Mono;
 
 import java.text.DecimalFormat;
-import java.util.ArrayList;
-import java.util.List;
+import java.util.*;
 
 @Service
 @Slf4j
 @RequiredArgsConstructor
 public class RouteService {
 
     private final ObjectMapper objectMapper;
+    private final GraphHopper graphHopper;
 
     @Value("${tmap.api.key}")
     private String tmapAPIKey;
@@ -144,10 +153,61 @@ private PositionDTO makeStopOver(PositionDTO start, PositionDTO end) {
 
         Double d = 0.0011;
 
+        double lat, lon;
         if (gradation > 0) {
-            return new PositionDTO(positionLat-unitLon*d, positionLon+unitLat*d); // 시계방향 회전
+            lat = positionLat-unitLon*d;
+            lon = positionLon-unitLat*d; // 시계방향 회전
         } else {
-            return new PositionDTO(positionLat+unitLon*d, positionLon-unitLat*d); // 반시계방향 회전
+            lat = positionLat+unitLon*d;
+            lon = positionLon-unitLat*d; // 반시계방향 회전
         }
+        return nearestIntersection(lat, lon);
+    }
+
+    public PositionDTO nearestIntersection(double lat, double lon) {
+        BaseGraph baseGraph = graphHopper.getBaseGraph();
+        NodeAccess nodeAccess = baseGraph.getNodeAccess();
+        EdgeExplorer edgeExplorer = baseGraph.createEdgeExplorer();
+
+        LocationIndex locationIndex = graphHopper.getLocationIndex();
+
+        Snap closest = locationIndex.findClosest(lat, lon, EdgeFilter.ALL_EDGES);
+
+        int closestNodeId = closest.getClosestNode();
+        int intersectionId = findNearestIntersectionBFS(closestNodeId, baseGraph, edgeExplorer);
+
+        return new PositionDTO(nodeAccess.getLat(intersectionId), nodeAccess.getLon(intersectionId));
+    }
+
+    private int findNearestIntersectionBFS(int startNodeId, BaseGraph baseGraph, EdgeExplorer explorer) {
+        Queue<Integer> queue = new LinkedList<>();
+        Set<Integer> visited = new HashSet<>();
+
+        queue.add(startNodeId);
+        visited.add(startNodeId);
+
+        while (!queue.isEmpty()) {
+            int curr = queue.poll();
+
+            int edgeCount = 0;
+            var edgeIterator = explorer.setBaseNode(curr);
+            while (edgeIterator.next()) {
+                edgeCount += 1;
+            }
+
+            if (edgeCount >= 3) {
+                return curr;
+            }
+
+            edgeIterator = explorer.setBaseNode(curr);
+            while (edgeIterator.next()) {
+                int nextId = edgeIterator.getAdjNode();
+                if (!visited.contains(nextId)) {
+                    visited.add(nextId);
+                    queue.add(nextId);
+                }
+            }
+        }
+        return -1;
     }
 }

backend/src/main/resources/application.properties

@@ -45,6 +45,6 @@ jwt.refresh-expiration=${REFRESH_TOKEN_EXPIRATION}
 #Tmap api
 tmap.api.key=${TMAP_API_KEY}
 
-#Naver api
+# Naver api
 naver.api.clientId=${NAVER_CLIENT_ID}
 naver.api.clientSecret=${NAVER_CLIENT_SECRET}