Web.config transformations have been around for a while now, and a lot of developers use them in their staple day-to-day environment deployment strategies – hell, Scott Hanselman was spouting about them way back in the beginning on 2010 with his “Web Deployment Made Awesome: If you’re using XCOPY, you’re doing it wrong” post. As usual though, one size does not fit all – and in the case of Continuous Integration fans out there that may have specific build-configuration-based build and deployment scenarios (such as myself), there is the need to have finer grained control over the Web.config transformation process. If this sounds like you, then this post is aimed to deliver.
Deploying in an automated fashion using Continuous Integration doesn’t happen instantly, and depending on the size of your application, your continuous integration deployment can get caught in a state of unknown/in-between if a user visits your application half way through deployment. This can be far from optimal, but ASP.Net has a trick up it’s sleave in the form of the App_offline.htm file.
Having a good Continuous Integration setup can be one of the highlights of any developers daily grind. Regardless, it can be seen as almost pointless if your automated deployment setup still needs a physical person to upload the files to your server if it is offsite. Adding FTP/SFTP to your CI process is the solution to this.