Tim Anderson's ITWriting

November 17, 2004

Future Exchange API will be web services

At Microsoft's IT Forum in Copenhagen, Exchange Senior Director Kim Akers told me a little about future plans for the Exchange API. Currently Exchange development is possible using a variety of APIs such as MAPI, CDO (Collaboration Data objects), COM add-ins and server-side scripts and extensions. It's all a bit messy, especially those APIs which really target the client rather than going directly to the Exchange back end. A web service based API makes enormous sense. Here are a few things you should be able to do:

Fire up Visual Studio .NET, set a web reference to one or two Exchange web services, and write your Windows Forms or ASP.NET application which queries and writes to Exchange contacts, tasks, messages or calendar entries.

Write a Java Exchange client which works the same on Mac OS X and on Linux.

Use the Compact Framework to write a little mobile application that automatically queries Exchange to check availablity, set up meetings, or send emails that progress new orders or other business transactions.

Of course I'm speculating - but if Exchange does get a standards-based web services API all this should be possible.

It's also worth noting that you can do these things today using the WebDAV API - so why is Microsoft moving from WebDAV to web services? I suspect the answer is that web services are just easier to work with, provided of course that you don't run into obscure SOAP compatibility or interoperability issues.

As to when - nothing announced yet, sadly.