chore: supports retaining file modification date

src/main/kotlin/app/termora/transfer/FileTransfer.kt

@@ -1,12 +1,19 @@
 package app.termora.transfer
 
+import app.termora.database.DatabaseManager
 import org.apache.commons.io.IOUtils
+import org.apache.sshd.sftp.client.fs.SftpFileSystem
+import org.apache.sshd.sftp.common.SftpConstants
+import org.slf4j.LoggerFactory
 import java.io.Closeable
 import java.io.InputStream
 import java.io.OutputStream
+import java.nio.file.Files
 import java.nio.file.Path
 import java.nio.file.StandardOpenOption
+import java.nio.file.attribute.BasicFileAttributeView
 import java.util.concurrent.atomic.AtomicBoolean
+import kotlin.io.path.getLastModifiedTime
 import kotlin.io.path.inputStream
 import kotlin.io.path.outputStream
 
@@ -15,10 +22,13 @@ class FileTransfer(
     private val action: TransferAction,
     priority: Transfer.Priority = Transfer.Priority.Normal,
 ) : AbstractTransfer(parentId, source, target, false, priority), Closeable {
+    companion object {
+        private val log = LoggerFactory.getLogger(FileTransfer::class.java)
+    }
 
     private lateinit var input: InputStream
     private lateinit var output: OutputStream
-
+    private val isPreserveModificationTime get() = DatabaseManager.getInstance().sftp.preserveModificationTime
     private val closed = AtomicBoolean(false)
 
     override suspend fun transfer(bufferSize: Int): Long {
@@ -31,7 +41,7 @@ class FileTransfer(
 
         if (::output.isInitialized.not()) {
             output = if (action == TransferAction.Overwrite) {
-                target().outputStream(StandardOpenOption.CREATE, StandardOpenOption.TRUNCATE_EXISTING)
+                target().outputStream()
             } else {
                 target().outputStream(StandardOpenOption.WRITE, StandardOpenOption.APPEND)
             }
@@ -40,6 +50,7 @@ class FileTransfer(
         val buffer = ByteArray(bufferSize)
         val len = input.read(buffer)
         if (len <= 0) return 0
+
         output.write(buffer, 0, len)
         return len.toLong()
     }
@@ -61,6 +72,24 @@ class FileTransfer(
             if (::output.isInitialized) {
                 IOUtils.closeQuietly(output)
             }
+
+            if (isPreserveModificationTime) {
+                runCatching {
+                    val time = source().getLastModifiedTime()
+                    val fs = target().fileSystem
+                    // SFTP 比较特殊
+                    if (fs is SftpFileSystem && fs.version == SftpConstants.SFTP_V3) {
+                        val view = Files.getFileAttributeView(target(), BasicFileAttributeView::class.java)
+                        view.setTimes(time, time, null)
+                    } else {
+                        Files.setLastModifiedTime(target(), time)
+                    }
+                }.onFailure {
+                    if (log.isWarnEnabled) {
+                        log.error(it.message, it)
+                    }
+                }
+            }
         }
     }