Remote File Watcher Action Plugin



Overview

This action plugin waits for the arrival of files matching a certain pattern on a remote Aspera server.

Saved Parameters Description

Details:

Inputs Description

The list of inputs depends on the configuration of the RemoteFileWatcher action template.

Changes in this list of inputs will override any values set in the action template.

Outputs Description

Supported Actions

None

Dependencies

None

Operating Instructions

Overview:

This action detects new files or folders matching a certain pattern, located below a watch directory in a remote server. Both the pattern matching and the directory path must be provided by the user. The directory may be searched a single time for a matching file (do not select keep on-going) or can be treated similarly to a hot folder where it is continually scanned for matching files (select keep on-going). Matching file presence can also be checked (select check only once), going on the failure path if no matching file is found.

Instructions:

Populate the watch directory field with the directory to be scanned for trigger files. Globbing pattern matching is used in watch directory.

If the trigger file can appear in a sub directory directly below this "root" directory, then it is important to place a wild card in the Watch directory name to tell the system that it is necessary to traverse through the sub folder to search for the file. For example, to traverse the first directory the path could be something like "/foo/bar/*". This will instruct the system to search the first directory below "bar" for the trigger file (e.g. detecting /foo/bar/toto.txt).

To detect files one more level down the path, you can use the Descend in sub directories? flag. If the trigger file can only appear in the root directory (or in a given directory), it is not advantageous to use the Descend in sub directories? flag for performance reasons.

Other example: /fo? will match /foo or /fo1 but not /foo1

The search is case sensitive.

Populate the file pattern field with the file name or file pattern used for the trigger.

Regular pattern matching is used for file pattern. Entering .*\.txt will result in all files with the .txt extension being identified as a trigger. Multiple patterns can be entered with (.*\.mxf|.*\.mpg)

It works for remote nodes installed with an Aspera transfer server (for example, Point to Point) as it uses the Aspera ascmd executable to browse files. The remote node must run an SSH server because SSH is used for authentication purposes. The remote user name must be an operating system account that must be defined in /opt/aspera/etc/aspera.conf on the remote server. The path to configure in the watch directory is relative to the remote user docroot as declared in /opt/aspera/etc/aspera.conf such as:

                       <user> 
                        <name>xfer</name> 
                        <file_system> 
                            <access> 
                                <paths> 
                                    <path> 
                                        <absolute>/home/xfer/data</absolute> 
                                    </path> 
                                </paths> 
                            </access> 
                        </file_system> 
                        </user>

For example, a watch directory like "/foo" refers to "/home/xfer/data/foo" on the remote server. Also the files/folders need to have the right permissions for the given remote user in order to be detected.

Select the checkbox "Keep trigger on-going" if it is necessary to periodically scan for files and folders arriving into the Watch directory and act upon their arrival. "Check only once" and "Keep trigger on-going" are incompatible options (do not select both of them).

If it is OK to trigger on a partial file, select "Triggers on partial file". This will allow processing to begin before the trigger file has been completely updated.