since v10.0.42

The extension point AttachmentDatasourceProvider is a java interface that provides access to the binary data of an attachment. The unique key to identify an attachment is it's UID in conjunction with the scheme. The scheme identifies the external source.

Access to the binary data of an attachment can be requested at any time and from within any process of the application. (e.g. attachment download request by GUI, attachment retrieval during outbound message processing)

The AttachmentDatasourceProvider returns an AttachmentDataSource that provides an InputStream to access the data. Only those AttachmentDatasourceProvider with corresponding schemes are invoked to retrieve the attachment's binary data.