Custom Web Publishing Versus XML Export

At first view, Custom Web Publishing might sound a lot like the XML Export capability we discussed in Chapter 20, "Getting Data Out of FileMaker." There are some similarities, but there are also many significant differences. The main ones are these:

• XML export is a "push" technology rather than a "pull" technology. New data becomes available to potential clients only when you decide to publish the data by performing a new export, possibly manually, possibly via an automated script. CWP is a server-side technology that can be made available on demand, enabling clients to pull new data at any time by accessing a specific URL that you provide.
• Using CWP, you can publish your FileMaker data in a new XML grammar, called fmresultset. This new grammar has the richness of the FMPXMLRESULT grammar, while being easier to work with for stylesheet writers. The grammar is available only through CWP.
• CWP is a server-side technology, which means you don need a copy of the FileMaker client to take advantage of CWP. All necessary programming occurs on the server side. On the other hand, exporting XML can take place only from a client application.

To sum up: Use XML export for occasional exports of FileMaker data as raw or transformed XML that you trigger through a client copy of FileMaker Pro. Use CWP when you want to provide live, on-demand access to FileMaker data via a web interface.