스프링 프레임워크(Spring Framework)-썸네일 이미지

개발 환경

java 21.0.4 2024-07-16 LTSJava(TM) SE Runtime Environment (build 21.0.4+8-LTS-274)

Java HotSpot(TM) 64-Bit Server VM (build 21.0.4+8-LTS-274, mixed mode, sharing)

 

Tomcatv 10.1

EclipseVersion: 2024-06 (4.32.0)Build id: 20240606-1231

---

pom.xml

<!-- https://mvnrepository.com/artifact/net.coobird/thumbnailator -->
<dependency>
    <groupId>net.coobird</groupId>
    <artifactId>thumbnailator</artifactId>
    <version>0.4.20</version>
</dependency>

---

web.xml

"<multipart-config>" 을 추가합니다.

<servlet>
    <servlet-name>dispatcherServlet</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <init-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>classpath:dispatcherServlet.xml</param-value>
    </init-param>
    <load-on-startup>1</load-on-startup>

    <multipart-config>
        <location>/tmp</location> <!-- 임시 파일 저장 경로 -->
        <max-file-size>5242880</max-file-size> <!-- 파일당 최대 크기 5MB -->
        <max-request-size>20971520</max-request-size> <!-- 전체 요청 최대 크기 20MB -->
        <file-size-threshold>0</file-size-threshold>
    </multipart-config>
</servlet>

---

controller

package com.thumbnail.controller;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.UUID;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.multipart.MultipartFile;
import org.springframework.web.servlet.ModelAndView;

import jakarta.servlet.ServletOutputStream;
import jakarta.servlet.http.HttpServletResponse;
import net.coobird.thumbnailator.Thumbnails;

@Controller
public class ThumbnailController {

	private String getFileExtension(String fileName) {
		if (fileName != null && fileName.contains(".")) {
			return fileName.substring(fileName.lastIndexOf(".") + 1);
		}
		return "";
	}

	@RequestMapping(value="/downloadThumbnail", method=RequestMethod.GET)
	public void downloadThumbnail(
			@RequestParam("fileName") String fileName, 
			HttpServletResponse response
	) throws Exception {
		ServletOutputStream out = response.getOutputStream();
		String filePath = "/Users/jangjeonghun/eclipse-workspace/uploadedFiles/" + fileName;
		
		File image = new File(filePath);
		int lastIndex = fileName.lastIndexOf(".");
		String fileNameWithoutExtension = fileName.substring(0, lastIndex);
		
		File thumbnail = new File("/Users/jangjeonghun/eclipse-workspace/uploadedFiles/thumbnail/" + fileNameWithoutExtension + ".png");
		if(image.exists()) {
			thumbnail.getParentFile().mkdir();
			Thumbnails.of(image).size(50,50).outputFormat("png").toFile(thumbnail);
		}
		
		FileInputStream in = new FileInputStream(thumbnail);
		byte[] buffer = new byte[1024 * 8];
		while(true) {
			int count = in.read(buffer);
			if(count == -1) { break; }
			
			out.write(buffer, 0, count);
		}
		
		in.close();
		out.close();
	}
	
	@RequestMapping(value="downloadThumbnailWithoutFile", method=RequestMethod.GET)
	public void downloadThumbnailWithoutFile(
			@RequestParam("fileName") String fileName,
			HttpServletResponse response
	) throws Exception {
		ServletOutputStream out = response.getOutputStream();
		String filePath = "/Users/jangjeonghun/eclipse-workspace/uploadedFiles/" + fileName;
		
		File image = new File(filePath);
		if(image.exists()) {
			Thumbnails.of(image).size(50,50).outputFormat("png").toOutputStream(out);
		} else {
			return;
		}
		
		byte[] buffer = new byte[1024 * 8];
		out.write(buffer);
		out.close();
	}
	
	@RequestMapping(value="/uploadThumbnail", method=RequestMethod.GET)
	public ModelAndView uploadThumbnailGet() {
		ModelAndView modelAndView = new ModelAndView("uploadThumbnail");
		
		return modelAndView;
	}
	
	@RequestMapping(value="/uploadThumbnail", method=RequestMethod.POST)
	public ModelAndView uploadThumbnailPost(@RequestParam("files") MultipartFile[] files) {
		ModelAndView modelAndView = new ModelAndView("uploadThumbnail");
		String uploadDir = "/Users/jangjeonghun/eclipse-workspace/uploadedFiles";
		
		List<String> failedFiles = new ArrayList<String>();
		List<String> allowedExtensions = Arrays.asList("jpg", "jpeg", "png", "gif", "pdf");
		
        for (MultipartFile file : files) {
            if (file.isEmpty()) {
                continue;
            }
            
            try {
                Path uploadPath = Paths.get(uploadDir);
                if (!Files.exists(uploadPath)) {
                    Files.createDirectories(uploadPath);
                }
                
                String originalFileName = file.getOriginalFilename();
    			String fileExtension = getFileExtension(originalFileName);

    			// 확장자 제한 체크
    			if (!allowedExtensions.contains(fileExtension.toLowerCase())) {
    				failedFiles.add(String.format("%s(허용되지 않는 확장자 파일)", originalFileName));
    				continue;
    			}
    			
    			// 파일명 중복 방지
                String uniqueFileName = String.format("%s_%s", UUID.randomUUID().toString(), originalFileName);

                // 파일 저장
                Path filePath = uploadPath.resolve(uniqueFileName);
                Files.copy(file.getInputStream(), filePath);
                
                modelAndView.addObject("fileName", uniqueFileName);
            } catch (IOException e) {
                e.printStackTrace();
                failedFiles.add(String.format("%s(업로드 실패)", file.getOriginalFilename()));
            }
        }
        
        if(failedFiles.isEmpty()) {
        	modelAndView.addObject("message", "파일 업로드가 완료 되었습니다.");
        } else {
        	modelAndView.addObject("message", String.join(",", failedFiles));
        }
		
		return modelAndView;	
	}
	
}

---

View

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8" isELIgnored="false"%>
<%@ taglib prefix="c" uri="jakarta.tags.core" %>

<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>
	<form action="${ contextPath }/uploadThumbnail" method="post" enctype="multipart/form-data">
		<label>파일</label><br><br>
		<input type="file" name="files" multiple />
		<br><br>
		
		<input type="submit" value="send data" />
	</form>
	<br>
	
	<%-- <p>fileName= ${ fileName }</p>
	<c:if test="${ not empty fileName }">
		<img src="/downloadThumbnail?fileName=${ fileName }" />
	</c:if> --%>
	
	<p>fileName without thumbnail file = ${ fileName }</p>
	<c:if test="${ not empty fileName }">
		<img src="/downloadThumbnailWithoutFile?fileName=${ fileName }" />
	</c:if>
</body>
</html>