sftp

name	sftp
description	JSch SFTP-mønstre: SftpConfig.channel {} livssyklus, FtpService fil-operasjoner, Directories enum og SftpListener integrasjonstest-fixture

SFTP Patterns

SFTP-mønstre med JSch: SftpConfig.channel {}, FtpService, Directories og SftpListener for testing.

This project uses JSch (com.github.mwiede:jsch) for SFTP. Authentication is RSA private key only — no password auth. All SFTP operations go through SftpConfig.channel {}, which opens a session + channel and closes them in finally.

SftpConfig — session/channel lifecycle

Never open JSch sessions or ChannelSftp channels directly in service code. Always use SftpConfig.channel {}:

class SftpConfig(
    private val sftpProperties: SftpProperties = PropertiesConfig.sftpProperties,
) {
    private val jsch: JSch =
        JSch().apply {
            JSch.setLogger(JSchLogger())
            addIdentity(
                sftpProperties.privateKeyFilePath,
                sftpProperties.trimmedPrivateKeyPassword,
            )
        }

    fun <T> channel(operation: (ChannelSftp) -> T): T {
        var session: Session? = null
        var sftpChannel: ChannelSftp? = null
        try {
            session = jsch.getSession(
                sftpProperties.trimmedUsername,
                sftpProperties.host,
                sftpProperties.port,
            ).apply {
                setConfig("StrictHostKeyChecking", "no")
                connect()
            }
            sftpChannel = (session.openChannel("sftp") as ChannelSftp).apply { connect() }
            return operation(sftpChannel)
        } finally {
            sftpChannel?.disconnect()
            session?.disconnect()
        }
    }
}

SftpProperties.trimmedUsername and trimmedPrivateKeyPassword strip whitespace from Vault-sourced values — always use the trimmed getters.

Directories enum

Use the Directories enum for all path references — never hardcode strings:

enum class Directories(val value: String) {
    OUTBOUND("/outbound"),
    INBOUND("/inbound"),
    FAILED("/inbound/feilfiler"),
}

Sub-files

• See ftp-service.md for FtpService (file operations, FtpFil data class) and JSchLogger.
• See sftp-listener.md for SftpListener integration test fixture.

Boundaries

✅ Always

• Use SftpConfig.channel {} — never open JSch sessions directly in service or test code
• Use Directories enum for paths
• Use sftpProperties.trimmedUsername and trimmedPrivateKeyPassword
• Route JSch ERROR/FATAL logs through TEAM_LOGS_MARKER
• Download files sorted alphabetically (listFiles().sorted())
• Move failed files to Directories.FAILED before persisting validation errors

🚫 Never

• Set StrictHostKeyChecking = yes in production (not supported by the SFTP server)
• Keep sessions open across multiple operations (open/close per channel {} call)
• Log JSch session details (host, key material) outside TEAM_LOGS_MARKER