When processing a file or a collection of files, the file name often contains valuable information about the contents. Also, it's important to capture the file name for quality control purposes. CloverETL allows you to access the filename of a file being processed using the special auto_filling property on Readers like XLSDataReader.
For example, in this graph, I record the filename used in XLSDataReader in the DBOutputTable. The XLSDataReader will process more than one file. It's file URL contains the wildcarded value "*_enrollments_*.xlsx" which will expand to filenames like "us_md_enrollments_fy2006.xlsx".
|CloverETL Graph Using auto_filling|
XLSDataReader's output port has the following metadata.
|CloverETL XLSDataReader Output Port Metadata|
Since it's added to the schema, the source_name field is able to be used in other component. For example, the Graph in this post uses source_name (carried in the "Filename" field), in a Reformat column.
There are other file-based items that may be of interest. Check the CloverETL Wiki for a list of what else is available.