GH-8745: Add RFT.shouldMarkSessionAsDirty()

spring-integration-file/src/main/java/org/springframework/integration/file/remote/RemoteFileTemplate.java

@@ -451,27 +451,42 @@ public <T> T execute(SessionCallback<F, T> callback) {
 			}
 			return callback.doInSession(session);
 		}
-		catch (Exception e) {
-			if (session != null) {
+		catch (Exception ex) {
+			if (session != null && shouldMarkSessionAsDirty(ex)) {
 				session.dirty();
 			}
-			if (e instanceof MessagingException) { // NOSONAR
-				throw (MessagingException) e;
+			if (ex instanceof MessagingException messagingException) { // NOSONAR
+				throw messagingException;
 			}
-			throw new MessagingException("Failed to execute on session", e);
+			throw new MessagingException("Failed to execute on session", ex);
 		}
 		finally {
 			if (!invokeScope && session != null) {
 				try {
 					session.close();
 				}
-				catch (Exception ignored) {
-					this.logger.debug("failed to close Session", ignored);
+				catch (Exception ex) {
+					this.logger.debug("failed to close Session", ex);
 				}
 			}
 		}
 	}
 
+	/**
+	 * Determine whether {@link Session#dirty()} should be called
+	 * in the {@link #execute(SessionCallback)} when an exception is thrown from the callback.
+	 * By default, this method returns {@code true}.
+	 * Remote file protocol extensions can override this method to provide
+	 * a specific strategy against the thrown exception, e.g. {@code file not found} error
+	 * is not a signal that session is broken.
+	 * @param ex the exception to check if {@link Session} must be marked as dirty.
+	 * @return true if {@link Session#dirty()} should be called.
+	 * @since 6.0.8
+	 */
+	protected boolean shouldMarkSessionAsDirty(Exception ex) {
+		return true;
+	}
+
 	@Override
 	public <T> T invoke(OperationsCallback<F, T> action) {
 		Session<F> contextSession = this.contextSessions.get();
@@ -503,8 +518,7 @@ public <T, C> T executeWithClient(ClientCallback<C, T> callback) {
 	private StreamHolder payloadToInputStream(Message<?> message) throws MessageDeliveryException {
 		Object payload = message.getPayload();
 		try {
-			if (payload instanceof File) {
-				File inputFile = (File) payload;
+			if (payload instanceof File inputFile) {
 				if (inputFile.exists()) {
 					return new StreamHolder(
 							new BufferedInputStream(new FileInputStream(inputFile)), inputFile.getAbsolutePath());
@@ -526,8 +540,7 @@ else if (payload instanceof byte[] || payload instanceof String) {
 			else if (payload instanceof InputStream) {
 				return new StreamHolder((InputStream) payload, "InputStream payload");
 			}
-			else if (payload instanceof Resource) {
-				Resource resource = (Resource) payload;
+			else if (payload instanceof Resource resource) {
 				String filename = resource.getFilename();
 				return new StreamHolder(resource.getInputStream(), filename != null ? filename : "Resource payload");
 			}
@@ -619,16 +632,7 @@ else if (!directoryPath.endsWith(this.remoteFileSeparator)) {
 		}
 	}
 
-	private static final class StreamHolder {
-
-		private final InputStream stream;
-
-		private final String name;
-
-		StreamHolder(InputStream stream, String name) {
-			this.stream = stream;
-			this.name = name;
-		}
+	private record StreamHolder(InputStream stream, String name) {
 
 	}
 

spring-integration-ftp/src/main/java/org/springframework/integration/ftp/session/FtpRemoteFileTemplate.java

@@ -20,10 +20,12 @@
 
 import org.apache.commons.net.ftp.FTPClient;
 import org.apache.commons.net.ftp.FTPFile;
+import org.apache.commons.net.ftp.FTPReply;
 
 import org.springframework.integration.file.remote.ClientCallback;
 import org.springframework.integration.file.remote.RemoteFileTemplate;
 import org.springframework.integration.file.remote.session.SessionFactory;
+import org.springframework.lang.Nullable;
 import org.springframework.messaging.MessagingException;
 import org.springframework.util.Assert;
 import org.springframework.util.ObjectUtils;
@@ -34,6 +36,7 @@
  *
  * @author Gary Russell
  * @author Artem Bilan
+ *
  * @since 4.1
  *
  */
@@ -82,29 +85,50 @@ protected <T> T doExecuteWithClient(final ClientCallback<FTPClient, T> callback)
 	public boolean exists(final String path) {
 		return doExecuteWithClient(client -> {
 			try {
-				switch (FtpRemoteFileTemplate.this.existsMode) {
-
-					case STAT:
-						return client.getStatus(path) != null;
-
-					case NLST:
-						String[] names = client.listNames(path);
-						return !ObjectUtils.isEmpty(names);
-
-					case NLST_AND_DIRS:
-						return FtpRemoteFileTemplate.super.exists(path);
-
-					default:
-						throw new IllegalStateException("Unsupported 'existsMode': " +
-								FtpRemoteFileTemplate.this.existsMode);
-				}
+				return switch (FtpRemoteFileTemplate.this.existsMode) {
+					case STAT -> client.getStatus(path) != null;
+					case NLST -> !ObjectUtils.isEmpty(client.listNames(path));
+					case NLST_AND_DIRS -> FtpRemoteFileTemplate.super.exists(path);
+				};
 			}
 			catch (IOException e) {
 				throw new MessagingException("Failed to check the remote path for " + path, e);
 			}
 		});
 	}
 
+	@Override
+	protected boolean shouldMarkSessionAsDirty(Exception ex) {
+		IOException ftpException = findIoException(ex);
+		if (ftpException != null) {
+			return isStatusDirty(ftpException.getMessage());
+		}
+		else {
+			return super.shouldMarkSessionAsDirty(ex);
+		}
+	}
+
+	/**
+	 * Check if {@link IOException#getMessage()} is treated as fatal.
+	 * @param ftpErrorMessage the value from {@link IOException#getMessage()}.
+	 * @return true if {@link IOException#getMessage()} is treated as fatal.
+	 * @since 6.0.8
+	 */
+	protected boolean isStatusDirty(String ftpErrorMessage) {
+		return !ftpErrorMessage.contains("" + FTPReply.FILE_UNAVAILABLE)
+				&& !ftpErrorMessage.contains("" + FTPReply.FILE_NAME_NOT_ALLOWED);
+	}
+
+	@Nullable
+	private static IOException findIoException(Throwable ex) {
+		if (ex == null || ex instanceof IOException) {
+			return (IOException) ex;
+		}
+		else {
+			return findIoException(ex.getCause());
+		}
+	}
+
 	/**
 	 * The {@link #exists(String)} operation mode.
 	 * @since 4.1.9

spring-integration-ftp/src/test/java/org/springframework/integration/ftp/session/FtpRemoteFileTemplateTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2014-2022 the original author or authors.
+ * Copyright 2014-2023 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -34,6 +34,7 @@
 import org.springframework.integration.file.DefaultFileNameGenerator;
 import org.springframework.integration.file.remote.ClientCallbackWithoutResult;
 import org.springframework.integration.file.remote.SessionCallbackWithoutResult;
+import org.springframework.integration.file.remote.session.Session;
 import org.springframework.integration.file.remote.session.SessionFactory;
 import org.springframework.integration.file.support.FileExistsMode;
 import org.springframework.integration.ftp.FtpTestSupport;
@@ -53,9 +54,7 @@
 /**
  * @author Gary Russell
  * @author Artem Bilan
- *
  * @since 4.1
- *
  */
 @SpringJUnitConfig
 @DirtiesContext
@@ -142,6 +141,25 @@ public void testConnectionClosedAfterExists() throws Exception {
 		assertThat(pool.getActiveCount()).isEqualTo(0);
 	}
 
+	@Test
+	public void sessionIsNotDirtyOnNoSuchFileError() {
+		Session<FTPFile> session = this.sessionFactory.getSession();
+		session.close();
+
+		FtpRemoteFileTemplate template = new FtpRemoteFileTemplate(this.sessionFactory);
+
+		assertThatExceptionOfType(MessagingException.class)
+				.isThrownBy(() -> template.rename("No_such_file1", "No_such_file2"))
+				.withRootCauseInstanceOf(IOException.class)
+				.withStackTraceContaining("553 : No such file or directory");
+
+		Session<FTPFile> newSession = this.sessionFactory.getSession();
+		assertThat(TestUtils.getPropertyValue(newSession, "targetSession"))
+				.isSameAs(TestUtils.getPropertyValue(session, "targetSession"));
+
+		newSession.close();
+	}
+
 	@Configuration
 	public static class Config {
 

spring-integration-sftp/src/main/java/org/springframework/integration/sftp/session/SftpRemoteFileTemplate.java

@@ -16,11 +16,16 @@
 
 package org.springframework.integration.sftp.session;
 
+import java.util.List;
+
 import org.apache.sshd.sftp.client.SftpClient;
+import org.apache.sshd.sftp.common.SftpConstants;
+import org.apache.sshd.sftp.common.SftpException;
 
 import org.springframework.integration.file.remote.ClientCallback;
 import org.springframework.integration.file.remote.RemoteFileTemplate;
 import org.springframework.integration.file.remote.session.SessionFactory;
+import org.springframework.lang.Nullable;
 
 /**
  * SFTP version of {@code RemoteFileTemplate} providing type-safe access to
@@ -34,6 +39,21 @@
  */
 public class SftpRemoteFileTemplate extends RemoteFileTemplate<SftpClient.DirEntry> {
 
+	protected static final List<Integer> NOT_DIRTY_STATUSES = // NOSONAR
+			List.of(
+					SftpConstants.SSH_FX_NO_SUCH_FILE,
+					SftpConstants.SSH_FX_NO_SUCH_PATH,
+					SftpConstants.SSH_FX_INVALID_FILENAME,
+					SftpConstants.SSH_FX_INVALID_HANDLE,
+					SftpConstants.SSH_FX_FILE_ALREADY_EXISTS,
+					SftpConstants.SSH_FX_DIR_NOT_EMPTY,
+					SftpConstants.SSH_FX_NOT_A_DIRECTORY,
+					SftpConstants.SSH_FX_EOF,
+					SftpConstants.SSH_FX_CANNOT_DELETE,
+					SftpConstants.SSH_FX_FILE_IS_A_DIRECTORY,
+					SftpConstants.SSH_FX_FILE_CORRUPT
+			);
+
 	public SftpRemoteFileTemplate(SessionFactory<SftpClient.DirEntry> sessionFactory) {
 		super(sessionFactory);
 	}
@@ -48,4 +68,35 @@ protected <T> T doExecuteWithClient(final ClientCallback<SftpClient, T> callback
 		return execute(session -> callback.doWithClient((SftpClient) session.getClientInstance()));
 	}
 
+	@Override
+	protected boolean shouldMarkSessionAsDirty(Exception ex) {
+		SftpException sftpException = findSftpException(ex);
+		if (sftpException != null) {
+			return isStatusDirty(sftpException.getStatus());
+		}
+		else {
+			return super.shouldMarkSessionAsDirty(ex);
+		}
+	}
+
+	/**
+	 * Check if {@link SftpException#getStatus()} is treated as fatal.
+	 * @param status the value from {@link SftpException#getStatus()}.
+	 * @return true if {@link SftpException#getStatus()} is treated as fatal.
+	 * @since 6.0.8
+	 */
+	protected boolean isStatusDirty(int status) {
+		return !NOT_DIRTY_STATUSES.contains(status);
+	}
+
+	@Nullable
+	private static SftpException findSftpException(Throwable ex) {
+		if (ex == null || ex instanceof SftpException) {
+			return (SftpException) ex;
+		}
+		else {
+			return findSftpException(ex.getCause());
+		}
+	}
+
 }

spring-integration-sftp/src/test/java/org/springframework/integration/sftp/session/SftpRemoteFileTemplateTests.java

@@ -22,6 +22,7 @@
 
 import org.apache.sshd.sftp.client.SftpClient;
 import org.apache.sshd.sftp.client.SftpVersionSelector;
+import org.apache.sshd.sftp.common.SftpException;
 import org.junit.jupiter.api.Test;
 
 import org.springframework.beans.factory.BeanFactory;
@@ -38,6 +39,7 @@
 import org.springframework.integration.file.support.FileExistsMode;
 import org.springframework.integration.sftp.SftpTestSupport;
 import org.springframework.integration.test.condition.LogLevels;
+import org.springframework.integration.test.util.TestUtils;
 import org.springframework.messaging.MessageDeliveryException;
 import org.springframework.messaging.MessagingException;
 import org.springframework.messaging.support.GenericMessage;
@@ -52,9 +54,7 @@
 /**
  * @author Gary Russell
  * @author Artem Bilan
- *
  * @since 4.1
- *
  */
 @SpringJUnitConfig
 @DirtiesContext
@@ -63,7 +63,7 @@ public class SftpRemoteFileTemplateTests extends SftpTestSupport {
 	@Autowired
 	private CachingSessionFactory<SftpClient.DirEntry> sessionFactory;
 
-	@LogLevels(level = "trace", categories = { "org.apache.sshd", "org.springframework.integration.sftp" })
+	@LogLevels(level = "trace", categories = {"org.apache.sshd", "org.springframework.integration.sftp"})
 	@Test
 	public void testINT3412AppendStatRmdir() {
 		SftpRemoteFileTemplate template = new SftpRemoteFileTemplate(sessionFactory);
@@ -164,6 +164,25 @@ public void renameWithOldSftpVersion() {
 		oldVersionSession.close();
 	}
 
+	@Test
+	public void sessionIsNotDirtyOnNoSuchFileError() {
+		Session<SftpClient.DirEntry> session = this.sessionFactory.getSession();
+		session.close();
+
+		SftpRemoteFileTemplate template = new SftpRemoteFileTemplate(this.sessionFactory);
+
+		assertThatExceptionOfType(MessagingException.class)
+				.isThrownBy(() -> template.list("No_such_dir"))
+				.withRootCauseInstanceOf(SftpException.class)
+				.withStackTraceContaining("(SSH_FX_NO_SUCH_FILE): No such file or directory");
+
+		Session<SftpClient.DirEntry> newSession = this.sessionFactory.getSession();
+		assertThat(TestUtils.getPropertyValue(newSession, "targetSession"))
+				.isSameAs(TestUtils.getPropertyValue(session, "targetSession"));
+
+		newSession.close();
+	}
+
 	@Configuration
 	public static class Config {