File listing service¶

This service provides an interface for retrieving and saving the list of files of a certain remote directory.

This may be coupled with the file transfer services, such as the CFDP service -- which implements it --, to provide remote directory listing capabilities.

Implementing classes may make use of a org.yamcs.filetransfer.FileListingParser in order to parse a provided file listing according to a certain specification (currently org.yamcs.filetransfer.BasicListingParser and org.yamcs.filetransfer.CsvListingParser exist).

Class Name¶

org.yamcs.filetransfer.FileListingService

Configuration¶

This service is defined in etc/yamcs.instance.yaml but its configuration is implementation specific. Here is an example of it being parametrised inside a file transfer service with a set file listing parser:

services:
  - class: org.yamcs.filetransfer.MyFileTransferService
    name: my-file-transfer
    args:
        fileListingServiceClassName: org.yamcs.filetransfer.MyFileListingService
        fileListingServiceArgs:
            automaticDirectoryListingReloads: false
            fileListingParserClassName: org.yamcs.filetransfer.BasicListingParser
            fileListingParserArgs:
                directoryTerminators: ["/"]

Configuration Options¶

The interface has no common parameters but these may be of use by certain implementations:

fileListingParserClassName: Class to use to parse the file listing data.
fileListingParserArgs: Arguments to pass to the FileListingParser used.

The implementation specific parameters (and defaults) can be found in their respective class:

CFDP service

Parser Configuration Options¶

Each implementation of the file listing parsers have their own parameters.

BasicListingParser¶

The BasicListingParser parses the file listing from a linebreak separated list of filenames. Directories are detected by checking whether the file name ends with a directory terminator.

removePrependingRemotePath (boolean): Whether the filenames in the file listing contain the remote path as a prefix. Default: true
directoryTerminators (list): Directory terminators, used to determine whether a file name corresponds to a directory. Parsing will remove all prepending and ending directory terminators. Default: ["/"]

CsvListingParser¶

The CsvListingParser parses the file listing from a Comma Separated Value text, with each line representing a file and each column one of its properties. Timestamps can be parsed as numbers or as strings in the ISO format.

useCsvHeader (boolean): Whether the parser should read the header of the CSV to determine what value goes to which property. Default: false
protobufColumnNumberMapping (map): Mapping of the RemoteFile protobuf field names to the column number of the CSV (not used if useCsvHeader is true). Default: Column numbers are the same as the protobuf's (same order of fields)
headerProtobufMapping (map): Mapping of the CSV column names in the header (when useCsvHeader is true) to the protobuf fields names of RemoteFile. Default: Same names as the protobuf fields
timestampMultiplier (float): If timestamps are parsed as numbers, the multiplier to use to get the result in milliseconds. Default: 1000