删除个文件夹，vfs2上传文件到ftp就异常553，这么不经事吗

开心一刻

今天逛街碰到街头采访，一上来就问我敏感话题

主持人：小哥哥，你单身吗

我：是啊

主持人：你找女朋友的话，是想找一个小奶猫呢，还是小野猫呢

我沉思了一下，叹气道：如果可以的话，我想找个人，而且是女人

上传文件

基于 commons-vfs2 实现文件到 FTP 服务器的上传，pom.xml 如下

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.qsl</groupId>
    <artifactId>ftp-demo</artifactId>
    <version>1.0-SNAPSHOT</version>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.7.18</version>
    </parent>

    <properties>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-vfs2</artifactId>
            <version>2.7.0</version>
        </dependency>
        <dependency>
            <groupId>commons-net</groupId>
            <artifactId>commons-net</artifactId>
            <version>3.9.0</version>
        </dependency>
    </dependencies>
</project>

application.yml

server:
  port: 8080

app:
  ftp:
    host: ftp_ip
    userName: ftp账号
    password: ftp账号的密码
    port: 21
    protocol: ftp
    baseDir: 账号基础目录

FtpConfig.java

/**
 * FTP 配置
 * @author 青石路
 */
@Configuration
@ConfigurationProperties(prefix = "app.ftp")
public class FtpConfig {

    private String host;
    private String userName;
    private String password;
    private Integer port;
    private String protocol;
    private String baseDir;

    @Bean("fptUri")
    public URI fptUri() throws URISyntaxException {
        return new URI(protocol, userName+":"+password, host,
                port, baseDir, null, null);
    }

    @Bean
    public FileSystemOptions fileSystemOptions() {
        FileSystemOptions opts = new FileSystemOptions();
        FtpFileSystemConfigBuilder builder = FtpFileSystemConfigBuilder.getInstance();
        builder.setControlEncoding(opts, "UTF-8");
        builder.setConnectTimeout(opts, 5000);
        builder.setUserDirIsRoot(opts, true);
        builder.setPassiveMode(opts, true);
        return opts;
    }

    public String getHost() {
        return host;
    }

    public void setHost(String host) {
        this.host = host;
    }

    public String getUserName() {
        return userName;
    }

    public void setUserName(String userName) {
        this.userName = userName;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public Integer getPort() {
        return port;
    }

    public void setPort(Integer port) {
        this.port = port;
    }

    public String getProtocol() {
        return protocol;
    }

    public void setProtocol(String protocol) {
        this.protocol = protocol;
    }

    public String getBaseDir() {
        return baseDir;
    }

    public void setBaseDir(String baseDir) {
        this.baseDir = baseDir;
    }
}

FileUploadManager.java 完成上传

/**
 * 文件上传 manager
 * @author 青石路
 */
@Component
public class FileUploadManager {

    private static final Logger LOGGER = LoggerFactory.getLogger(FileUploadManager.class);
    private static final FileSystemManager systemManager;

    @Autowired
    @Qualifier("fptUri")
    private URI fptUri;
    @Autowired
    private FileSystemOptions fileSystemOptions;

    static {
        try {
            systemManager = VFS.getManager();
        } catch (FileSystemException e) {
            throw new RuntimeException(e);
        }
    }

    public boolean uploadFileToSftp(File file, String fileName) {
        try {
            FileObject srcObject = systemManager.resolveFile(file.getParentFile(), file.getName());
            FileObject destObjectDir = systemManager.resolveFile(fptUri.toString(), fileSystemOptions);
            FileObject destObject = systemManager.resolveFile(destObjectDir, fileName);
            destObject.copyFrom(srcObject, Selectors.SELECT_SELF);
            return true;
        } catch (FileSystemException e) {
            LOGGER.error("文件:{} 上传SFTP失败，异常：", file.getAbsoluteFile(), e);
            return false;
        }
    }
}

FileUploadController.java

/**
 * 文件上传 controller
 * @author 青石路
 */
@RestController
@RequestMapping("file")
public class FileUploadController {

    private static final Logger LOGGER = LoggerFactory.getLogger(FileUploadController.class);

    @Autowired
    private FileUploadManager fileUploadManager;

    @GetMapping("upload")
    public boolean upload(@RequestParam("fileName") String fileName) {
        long ramdomLong = ThreadLocalRandom.current().nextLong();
        File file = new File(System.getProperty("java.io.tmpdir") + File.separator + ramdomLong + ".txt");
        LOGGER.info("localFile:{}", file.getAbsoluteFile());
        boolean uploadResult = false;
        try {
            Files.write(file.toPath(), String.valueOf(ramdomLong).getBytes(StandardCharsets.UTF_8));
            uploadResult = fileUploadManager.uploadFileToSftp(file, fileName);
        } catch (IOException e) {
            throw new RuntimeException(e);
        } finally {
            try {
                Files.deleteIfExists(file.toPath());
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }
        return uploadResult;
    }
}

完整代码：ftp-demo

FTP 服务器目录最初情况如下

/idg 下没有任何目录和文件；启动后调用接口

http://localhost:8080/file/upload?fileName=hello.txt

即可完成文件的上传；fileName 参数表示上传到 FTP 服务器上的文件名

true 表示上传成功，FTP 服务器上即可看到 hello.txt

file 目录也被自动创建了，一切都是那么的顺利

上传失败：553

一个不小心把 FTP 服务器上 file 目录给删了，但内心一点都不慌，再上传一次呗，正好我也是这么干的；正当我以为会正常上传的时候，意外来了

org.apache.commons.vfs2.FileSystemException: Could not copy "file:///C:/Users/qsl/AppData/Local/Temp/6456333409667879871.txt" to "ftp://test:***@192.168.2.118/idg/file/hello.txt".
	at org.apache.commons.vfs2.provider.AbstractFileObject.copyFrom(AbstractFileObject.java:303)
	at com.qsl.manager.FileUploadManager.uploadFileToSftp(FileUploadManager.java:47)
	at com.qsl.web.FileUploadController.upload(FileUploadController.java:39)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:205)
	at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:150)
	at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:117)
	at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:895)
	at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:808)
	at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)
	at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1072)
	at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:965)
	at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006)
	at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:898)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:529)
	at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:623)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:209)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:153)
	at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:51)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:178)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:153)
	at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:178)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:153)
	at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:178)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:153)
	at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:178)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:153)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:168)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:90)
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:481)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:130)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:93)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342)
	at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:390)
	at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:63)
	at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:928)
	at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1794)
	at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:52)
	at org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191)
	at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659)
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
	at java.lang.Thread.run(Thread.java:745)
Caused by: org.apache.commons.vfs2.FileSystemException: Could not write to "ftp://test:***@192.168.2.118/idg/file/hello.txt".
	at org.apache.commons.vfs2.provider.AbstractFileObject.getOutputStream(AbstractFileObject.java:1280)
	at org.apache.commons.vfs2.provider.DefaultFileContent.buildOutputStream(DefaultFileContent.java:540)
	at org.apache.commons.vfs2.provider.DefaultFileContent.getOutputStream(DefaultFileContent.java:406)
	at org.apache.commons.vfs2.provider.DefaultFileContent.getOutputStream(DefaultFileContent.java:394)
	at org.apache.commons.vfs2.provider.DefaultFileContent.write(DefaultFileContent.java:815)
	at org.apache.commons.vfs2.provider.DefaultFileContent.write(DefaultFileContent.java:830)
	at org.apache.commons.vfs2.util.FileObjectUtils.writeContent(FileObjectUtils.java:203)
	at org.apache.commons.vfs2.provider.AbstractFileObject.copyFrom(AbstractFileObject.java:298)
	... 52 common frames omitted
Caused by: org.apache.commons.vfs2.FileSystemException: Cant open output connection for file "ftp://test:***@192.168.2.118/idg/file/hello.txt". Reason: "553 Can't open that file: No such file or directory
".
	at org.apache.commons.vfs2.FileSystemException.requireNonNull(FileSystemException.java:87)
	at org.apache.commons.vfs2.provider.ftp.FtpFileObject.doGetOutputStream(FtpFileObject.java:519)
	at org.apache.commons.vfs2.provider.AbstractFileObject.getOutputStream(AbstractFileObject.java:1276)
	... 59 common frames omitted

553 Can't open that file: No such file or directory 是什么鬼？莫非是 file 目录不存在的原因？试着手动创建 file 目录，再调用接口上传文件，文件正常上传！

我们来分析下，最初的时候 file 目录是不存在的，但自动创建了，文件也正常上传了，然后我们手动删除 file 目录后，上传文件失败，手动补上 file 目录后，上传又正常了，这说明 file 目录被缓存了呀，对不对？最初的时候，缓存是空的，第一次上传的时候，vfs2 会判断 FTP 服务器上是否存在 file 目录，不存在则创建并进行缓存，那么下次上传的时候，在缓存中找到了 file 目录，那么就直接上传文件了，而不用去判断 FTP 服务器上是否有 file 目录（没有则创建）；缓存的作用就很明显了，减少了一次目录是否存在的网络请求，进而提高效率；当然这只是我们的猜想，是否真的存在缓存，看源码肯定是最直观的，入口代码

FileObject destObjectDir = systemManager.resolveFile(fptUri.toString(), fileSystemOptions);

就不带你们详细去跟源码了，debug 跟源码，我相信你们也很容易找到 AbstractFileSystem#resolveFile(final FileName name, final boolean useCache)

private synchronized FileObject resolveFile(final FileName name, final boolean useCache)
		throws FileSystemException {
	if (!rootName.getRootURI().equals(name.getRootURI())) {
		throw new FileSystemException("vfs.provider/mismatched-fs-for-name.error", name, rootName,
				name.getRootURI());
	}

	// imario@apache.org ==> use getFileFromCache
	FileObject file;
	if (useCache) {
		file = getFileFromCache(name);
	} else {
		file = null;
	}

	if (file == null) {
		try {
			file = createFile((AbstractFileName) name);
		} catch (final Exception e) {
			throw new FileSystemException("vfs.provider/resolve-file.error", name, e);
		}

		file = decorateFileObject(file);

		// imario@apache.org ==> use putFileToCache
		if (useCache) {
			putFileToCache(file);
		}
	}

	/**
	 * resync the file information if requested
	 */
	if (getFileSystemManager().getCacheStrategy().equals(CacheStrategy.ON_RESOLVE)) {
		file.refresh();
	}
	return file;
}

如何修复

首先我们讨论下：要不要修？

手动误删目录，这种情况是非常少的，就拿我们的生产来讲，2020 到现在，从未出现过该问题，如果因为这种极小概率的事件去放弃缓存带来的性能提升，得不偿失，所以我是不推荐修改的，而实际上经过讨论后也决定不去修改；不过话说回来，如果上传压力很小，网络又非常稳定、快速，也就说缓存带来的性能提升可以忽略，那这个时候高可用的优先级就更高了，此时就可以考虑修了，那怎么修了，我这里提供两种方案

1. 禁用缓存

   既然 vfs2 有缓存（默认是启用的），应该有开关来禁用它，我就不给你们打哑谜了，直接修改 FileSystemManager，换成其子类 StandardFileSystemManager

   private static final StandardFileSystemManager systemManager;
   
   static {
   	try {
   		systemManager = new StandardFileSystemManager();
           // 禁用缓存
   		systemManager.setFilesCache(new NullFilesCache());
   		systemManager.init();
   	} catch (FileSystemException e) {
   		throw new RuntimeException(e);
   	}
   }
   

   

   你们也许会问，我是怎么知道可以这么调整的，你们跟一下 VFS.getManager() 就知道了，最终会看到

   // managerClassName: org.apache.commons.vfs2.impl.StandardFileSystemManager
   private static FileSystemManager createFileSystemManager(final String managerClassName) throws FileSystemException {
   	try {
   		// Create instance
   		final Class<?> mgrClass = Class.forName(managerClassName);
   		final FileSystemManager mgr = (FileSystemManager) mgrClass.newInstance();
   
   		try {
   			// Initialize
   			final Method initMethod = mgrClass.getMethod("init", (Class[]) null);
   			initMethod.invoke(mgr, (Object[]) null);
   		} catch (final NoSuchMethodException ignored) {
   			/* Ignore; don't initialize. */
   		}
   
   		return mgr;
   	} catch (final InvocationTargetException e) {
   		throw new FileSystemException("vfs/create-manager.error", managerClassName, e.getTargetException());
   	} catch (final Exception e) {
   		throw new FileSystemException("vfs/create-manager.error", managerClassName, e);
   	}
   }
   

   通过反射调用了 StandardFileSystemManager 的构造方法和 init 方法，与我们的

   systemManager = new StandardFileSystemManager();
   systemManager.init();
   

   是不是有异曲同工之妙？（你们猜的没错，我们的实现正是抄自于 vfs2）

   

2. 异常弥补

   不禁用缓存，还是保留默认的开启，只是当异常的时候，捕获它，然后去创建目录，然后再上传一次

   public boolean uploadFileToSftp(File file, String fileName, boolean isRetry) {
   	String destDir = fptUri.toString();
   	try {
   		FileObject srcObject = systemManager.resolveFile(file.getParentFile(), file.getName());
   		FileObject destObjectDir = systemManager.resolveFile(destDir, fileSystemOptions);
   		FileObject destObject = systemManager.resolveFile(destObjectDir, fileName);
   		destObject.copyFrom(srcObject, Selectors.SELECT_SELF);
   		return true;
   	} catch (FileSystemException e) {
   		if (isRetry) {
   			try {
   				LOGGER.info("创建目录{}开始", destDir);
   				FileObject destObjectDir = systemManager.resolveFile(destDir, fileSystemOptions);
   				destObjectDir.createFolder();
   				LOGGER.info("创建目录{}开始", destDir);
   			} catch (FileSystemException ex) {
   				LOGGER.error("创建目录失败，异常：", ex);
   			}
   			return uploadFileToSftp(file, fileName, false);
   		}
   		LOGGER.error("文件:{} 上传SFTP失败，异常：", file.getAbsoluteFile(), e);
   		return false;
   	}
   }
   

   

   既保留了缓存，也解决了目录误删的问题，就问你们服不服？

   

总结

vfs2 是有缓存的，如果不小心把 FTP 目录删除了，上传会失败并提示

553 Can't open that file: No such file or directory

可以通过手动补目录的方式就行处理，当然也可以通过重启服务来解决，但这两种都不是通过代码来解决的，可用性很低；通过代码的方式来解决，有两种方法

1. 禁用 vfs2 缓存，但会降低性能，可用但不推荐

2. 异常弥补，既保留了缓存，也解决了目录误删的问题，可以用也推荐

   异常捕获后用来做流程控制，条件控制，不太规范