StructureMap 4.0 is Out!

tl;dr: StructureMap 4.0 went live to Nuget today with CoreCLR support, better performance, far better conventional registration via type scanning, and many improvements specifically targeted toward StructureMap integration into ASP.Net MVC 5 & 6 applications.

StructureMap 4.0 officially went live on Nuget today. The release notes page is updated for 4.0 and you can also peruse the raw GitHub issue list for the 4.0 milestone to see what’s new and what’s been fixed since 3.1.6.

Even though StructureMap has been around forever in .Net OSS terms (since June of 2004!), there are still new things to do, obsolete things to remove, and continuing needs to adapt to what users are actually trying to accomplish with the tool. As such, StructureMap 4.0 represents the lessons we’ve learned in the past couple years since the big 3.0 release. 4.0 is a much smaller set of changes than 3.0 and mostly contains performance and diagnostic improvements.

For the very first time since the long forgotten 2.5 release way back in 2008, I’m claiming that the StructureMap documentation site is completely up to date and effectively comprehensive. Failing that of course, the StructureMap Gitter room is open for questions.

This time around, I’d like to personally thank Kristian Hellang for being patient while we worked through issues with lifecycle and object disposal patterns for compliance with the new ASP.Net vNext dependency injection usage and the new StructureMap.DNX nuget for integrating StructureMap into vNext applications. I’d also like to thank Dmytro Dziuma for some pretty significant improvements to StructureMap runtime performance and his forthcoming packages for AOP with StructureMap and the rebuilt StructureMap.AutoFactory library. I’d also like to thank Oren Novotny for his help in moving StructureMap to the CoreCLR.

Some Highlights:

• The StructureMap nuget now targets .Net 4.0, the CoreCLR via the “dotnet” profile, and various Windows Phone and Android targets via the PCL. While the early feedback on CoreCLR usage has been positive, I think you still have to assume that that support is unproven and early.
• The internals of the type scanning and conventional registration has been completely overhauled to optimize container bootstrapping time and there are some new diagnostics to allow users to unwind frequent problems with type scanning registrations. The mechanism for custom conventions is a breaking change for 4.0, see the documentation for the details.
• The lifecycle management had to be significantly changed and enhanced for ASP.Net vNext compliance. More on this in a later blog post.
• Likewise, there are some new rules and behavior for how and when StructureMap will track and dispose IDisposable’s.
• Performance improvements in general and some optimizations targeted specifically at integration with ASP.Net MVC (I don’t approve of how the ASP.Net team has done their integration, but .Net is their game and it was important to harden StructureMap for their goofy usage)
• More robustness in heavy multi-threaded access
• The constructor selection is a little smarter
• ObjectFactory is gone, baby, gone. Jimmy Bogard will have to find some new reason to mock my code;)
• If you absolutely have to use them, there is better support for customizing registration and behavior with attributes
• The Registry class moved to the root “StructureMap” namespace, do watch that. That’s bugged me for years, so I went a head and fixed that this time since we were going for a new full point release.
• 4.0 introduces a powerful new mechanism for establishing policies and conventions on how objects are built at runtime. My hope is that this will solve some of the user questions and problems that I’ve gotten in the past couple years. There will definitely be follow up post on that.

And of course, you can probably expect a 4.0.1 release soon for any issues that pop up once folks use this in real project work. At a minimum, there’ll be updates for the CoreCLR support once the dust settles on all that churn.