SpringBoot 静态资源服务器

摘要：介绍springboot作为静态文件服务器的配置、上传文件到本地、本地文件下载的几种简要实现；实际使用则按需修改即可。

pom.xml配置

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    
    <dependency>
        <groupId>commons-io</groupId>
        <artifactId>commons-io</artifactId>
        <version>2.8.0</version>
    </dependency>
</dependencies>

application.yml配置

最好加上斜杠，因为不加斜杠你访问的路径则需要加上最后一个文件夹名称才能访问到文件

file:
  upload:
    local-storage: /data/

实际代码

• StaticsApplication.class

@SpringBootApplication(exclude = DataSourceAutoConfiguration.class)
public class StaticsApplication {

    public static void main(String[] args) {
        SpringApplication.run(StaticsApplication.class, args);
    }
}

• FileUploadProperties.class

用做配置属性

@Configuration
@Data
@ConfigurationProperties(prefix = FileUploadProperties.CONFIG_PREFIX)
public class FileUploadProperties {

    public static final String CONFIG_PREFIX = "file.upload";

    /** 存储路径 */
    private String localStorage;

}

• StaticResourceConfig.class

静态文件配置类，访问前缀

@Configuration
public class StaticResourceConfig implements WebMvcConfigurer {

    /** 必须这样 */
    private static final String FOLDER_PRE = "file:";

    @Autowired
    private FileUploadProperties fileUploadProperties;

    @Override
    public void addResourceHandlers(ResourceHandlerRegistry registry) {
        registry.addResourceHandler("/static-test/**").addResourceLocations(FOLDER_PRE + fileUploadProperties.getLocalStorage());
    }
}

• FileController.class

注意该上传写入文件有两种方式，一种是inputFile.transferTo(file);这种需要区分windows路径还是linux路径，windows则需要指定磁盘如D:/data/，推荐使用FileUtils.writeByteArrayToFile(file, inputFile.getBytes(), false);这种方式不用区分windows还是linux

@CrossOrigin
@RestController
@RequestMapping(value = "/file")
public class FileController {

    @Autowired
    private FileUploadProperties fileUploadProperties;

    @PostMapping("/upload")
    public String upload(@RequestParam("file") MultipartFile file) throws Exception{
        return this.uploadOneMultipleFile(file,Boolean.TRUE);
    }

    @GetMapping("/download")
    public void download(HttpServletResponse response,String fileName) throws Exception{
        File file = new File(fileUploadProperties.getLocalStorage()+fileName);
        if (!file.exists() || !file.isFile()){
            return;
        }
        InputStream inputStream = new FileInputStream(fileUploadProperties.getLocalStorage()+fileName);
        response.reset();
        response.setContentType("application/octet-stream");
        response.setHeader("Content-Disposition", "attachment;filename=" + fileName);
        ServletOutputStream outputStream = response.getOutputStream();
        byte[] b = new byte[1024];
        int len;
        try {
            while((len = inputStream.read(b)) > 0) {
                outputStream.write(b, 0, len);
            }
        } finally {
            inputStream.close();
        }
    }

    /**
     * 上传单文件
     * @param inputFile
     * @param isNewName
     * @return
     * @throws Exception
     */
    public String uploadOneMultipleFile(MultipartFile inputFile,boolean isNewName) throws Exception{
        String realName = inputFile.getOriginalFilename();
        if(isNewName){
            String ext = realName.substring(realName.lastIndexOf("."));
            realName = UUID.randomUUID().toString() + ext;
        }
        File file = makeDirsAndCreateFileName(fileUploadProperties.getLocalStorage(),realName);
        FileUtils.writeByteArrayToFile(file, inputFile.getBytes(), false);
        //inputFile.transferTo(file);
        return "/" + realName;
    }

    /**
     * 创建文件夹和文件
     * @param path
     * @param fileName
     * @return
     */
    private static File makeDirsAndCreateFileName(String path,String fileName){
        File file = new File(path);
        if(!file.exists()){
            file.mkdirs();
        }
        file = new File(path,fileName);
        return file;
    }

}