A system and various methods for simplifying or automating the task of configuring a graphical program to exchange data with a data source and/or data target. In response to receiving user input specifying a data source, the graphical program may be automatically, i.e., programmatically, configured to receive data from the data source. In response to receiving user input specifying a data target, the graphical program may be automatically, i.e., programmatically, configured to provide or write data to the data target. The data source or data target may be any of various types. For example, the data source or data target may be a file, a server, etc., and may be located on the host computer system of the graphical program or on a remote computer system. In the preferred embodiment, the data source or data target is specified by a uniform resource locator (URL).