Junfeng Zhang posts about a very powerful and complicated issue related to publisher policy, redirection cross major/minor version, and using the latest version in .NET, and also answers very pertinent questions about guidelines for SDK developers who deploy assemblies to be consumed by others in the comments section. My posted comment question: whether or not to reroute 3rd party applications to the latest shared SDK assemblies if deemed compatible. The short answer: to let 3rd party apps decide to float or not via app config files (which means redeployment/update of those configurations if they wish to support the latest), unless the support policy is to only support the latest version, in which case publisher policies are in order, in conjunction with compatibility (which is of course difficult b/c of seemingly innocuous changes which can break compat; e.g., inserting an enum member).

As a side note, it’s import to realize that you have to have a publisher policy for each major.minor version of assembly. So if you wish to provide publisher policies to reroute to your latest 2.0.0.0 assembly, assuming you started at 1.0.0.0, you would not only need a publisher policy for 1.0.0.0->2.0.0.0 but also for any minor releases such as 1.1.0.0 -> 2.0.0.0, 1.2.0.0 to 2.0.0.0, etc…

Junfeng Zhang mentions that the focus today is on side-by-side versioning, and not latest-only versioning, and I hope as well that this issue is attended to at some point. Nevertheless it’s nice to have a recommended approach for the time being, so thank you Junfeng.
- posted by Xavier @ 12:41 PM