A data source is a list of zero or many commands which fetch content from different content sources and produce XML. The resulting xml output is the input ("transformation-input") for XSLT to generate output documents.
Sometimes it makes sense to apply one or many intermediate steps to modify the loaded content before it becomes a "transformation-input". Possible reasons for this include
You might want to reuse the same XSLT to generate an output document for different content sources, but these content-sources do not produce the exactly same structure of input. An intermediate transformation step can be used to "normalize" the input among different content sources.
A complex transformation might be implement more elegant by splitting it into several subsequent steps.
A data-source-post-processinig.xlt can apply xml-transformations within the data-source object.
In the data-source-post-processing-xslt directory under the application, there are zero or more files, each describing a post-processing transformation step. Each file is a XSLT which expects input-data with a root tag <data-source-post-processing-input> and which shall produce any output xml with a root-tag <data-source-post-processing-output>.
Content loaded from source A:
Expected output:
You can add zero or many data-source-post-processing.xslt to each content-source of your data-source object. For each content-source post-processing will be executed separately. Multiple steps for the same content-source will be executed subsequently in the order of post-processing-xslt files.
In addition you can apply the same logic for the entire data-source object. In this case all content-sources are loaded as a first stept, and post-processing applies for the collection of all content-sources.