Merge pull request #3 from 4-Image-Module/feature/#2-UploadLibrary

Feat: #2 upload library

Author: CJ-1998

src/main/java/com/example/ImageModuleLibrary/upload/UploadLibrary.java

@@ -0,0 +1,138 @@
+package com.example.ImageModuleLibrary.upload;
+
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
+import org.springframework.core.io.ByteArrayResource;
+import org.springframework.http.HttpEntity;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.MediaType;
+import org.springframework.http.ResponseEntity;
+import org.springframework.util.LinkedMultiValueMap;
+import org.springframework.util.MultiValueMap;
+import org.springframework.web.client.RestTemplate;
+import org.springframework.web.multipart.MultipartFile;
+
+public class UploadLibrary {
+    private final RestTemplate restTemplate;
+
+    private static final String UPLOAD_URL = "http://localhost:19091/image/upload";
+    private static final String MULTI_UPLOAD_URL = "http://localhost:19091/image/upload/multi";
+
+    public UploadLibrary(RestTemplate restTemplate) {
+        this.restTemplate = restTemplate;
+    }
+
+    public String uploadImage(MultipartFile image, Integer size, Integer cachingTime) throws IOException {
+        // body 설정
+        MultiValueMap<String, Object> body = makeRequestBody(size, cachingTime, image);
+        ResponseEntity<String> responseEntity = sendRequest(UPLOAD_URL, body);
+        return getBody(responseEntity);
+    }
+
+    public List<String> uploadMultiImage(MultipartFile[] files, Integer[] sizes, Integer[] cachingTimes)
+            throws IOException {
+        MultiValueMap<String, Object> body = makeMultiRequestBody(files, sizes, cachingTimes);
+        ResponseEntity<String> responseEntity = sendRequest(MULTI_UPLOAD_URL, body);
+        return getMultiBody(responseEntity);
+    }
+
+    private static MultiValueMap<String, Object> makeMultiRequestBody(MultipartFile[] files, Integer[] sizes,
+                                                                      Integer[] cachingTimes)
+            throws IOException {
+        MultiValueMap<String, Object> body = new LinkedMultiValueMap<>();
+
+        for (int i = 0; i < files.length; i++) {
+            ByteArrayResource resource = getImageByteArrayResource(files[i]);
+            body.add("files", resource);
+            body.add("sizes", sizes[i]);
+            body.add("cachingTimes", cachingTimes[i]);
+        }
+        return body;
+    }
+
+    private ResponseEntity<String> sendRequest(String url, MultiValueMap<String, Object> body) {
+        // 헤더 설정
+        HttpHeaders headers = new HttpHeaders();
+        headers.setContentType(MediaType.MULTIPART_FORM_DATA);
+
+        // HttpEntity 생성
+        HttpEntity<MultiValueMap<String, Object>> requestEntity = new HttpEntity<>(body, headers);
+
+        return restTemplate.postForEntity(url, requestEntity, String.class);
+    }
+
+    private static MultiValueMap<String, Object> makeRequestBody(Integer size, Integer cachingTime,
+                                                                 MultipartFile image) throws IOException {
+        // form-data에 포함할 데이터 구성
+        MultiValueMap<String, Object> body = new LinkedMultiValueMap<>();
+
+        ByteArrayResource resource = getImageByteArrayResource(image);
+        body.add("file", resource);
+        body.add("size", size);
+        body.add("cachingTime", cachingTime);
+        return body;
+    }
+
+    private static List<String> getMultiBody(ResponseEntity<String> responseEntity) {
+        if (responseEntity.getStatusCode().is2xxSuccessful()) {
+
+            return getMultiSplitUUID(responseEntity);
+
+        } else {
+            throw new RuntimeException("Failed to upload image: " + responseEntity.getStatusCode());
+        }
+    }
+
+    private static List<String> getMultiSplitUUID(ResponseEntity<String> responseEntity) {
+        String answer = responseEntity.getBody();
+
+        String[] lines = answer.split("\n");
+
+        // 결과 리스트
+        List<String> resultList = new ArrayList<>();
+
+        for (int i = 0; i < lines.length; i++) {
+            if (lines[i].startsWith("event:SUCCESS")) {
+                String line = lines[i + 1];
+                String[] parts = line.split(":");
+                resultList.add(parts[2]);
+            }
+        }
+        return resultList;
+    }
+
+    private static String getBody(ResponseEntity<String> responseEntity) {
+        if (responseEntity.getStatusCode().is2xxSuccessful()) {
+            return getSplitUUID(responseEntity);
+
+        } else {
+            throw new RuntimeException("Failed to upload image: " + responseEntity.getStatusCode());
+        }
+    }
+
+    private static String getSplitUUID(ResponseEntity<String> responseEntity) {
+        String answer = responseEntity.getBody();
+        // 문자열을 줄 단위로 나누기
+        String[] lines = answer.split("\n");
+
+        String dataLine = lines[4].trim();
+        if (dataLine.startsWith("data:")) {
+            // data: 부분을 ':'로 나누고 두 번째 부분을 반환
+            return dataLine.split(":")[2].trim();
+        }
+        throw new RuntimeException("Data format is wrong: " + responseEntity.getStatusCode());
+    }
+
+    private static ByteArrayResource getImageByteArrayResource(MultipartFile image) throws IOException {
+        // 파일을 ByteArrayResource로 변환
+        byte[] bytes = image.getBytes();
+
+        return new ByteArrayResource(bytes) {
+            @Override
+            public String getFilename() {
+                return image.getOriginalFilename(); // 파일 이름 설정
+            }
+        };
+    }
+}