@memad ListSFTP does not actually fetch the content of any files from the target SFTP server. You would need a FetchSFTP processor after listSFTP to do that. The ListSFTP processor results in FlowFile(s) with metadata about the the listed file from the SFTP processor. This metadata is then used by the downstream FetchSFTP processor to retrieve the actual content for each FlowFile.
This metadata is present on the FlowFile as FlowFile attributes, and you can manipulate and do anything you like with this metadata.
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