Versioning long running workfows part 1

re: Versioning long running workfows part 1

Michael Washington — Sun, 05 Oct 2008 00:43:03 GMT

Thank you for this.

Versioning long running workflows part 4

WF Community Bloggers — Mon, 22 Sep 2008 12:56:59 GMT

Part 1 Part 2 Part 3 Part 4 In the previous blog posts we made sure we could have multiple versions of

Versioning long running workflows part 4

The Problem Solver — Mon, 22 Sep 2008 12:23:08 GMT

Part 1 Part 2 part 3 In the previous blog posts we made sure we could have multiple versions of the same

Versioning long running workfows part 3

WF Community Bloggers — Tue, 16 Sep 2008 15:03:39 GMT

Part 1 Part 2 In the first article of this series I demonstrated how to get multiple versions of a workflow

Versioning long running workfows part 3

The Problem Solver — Tue, 16 Sep 2008 14:29:08 GMT

Part 1 Part 2 In the first article of this series I demonstrated how to get multiple versions of a workflow

Versioning long running workflows part 2

WF Community Bloggers — Thu, 11 Sep 2008 19:09:41 GMT

Part 1 Part 2 In my previous post I demonstrated how to keep multiple versions of an assembly around

re: Versioning long running workfows part 1

Maurice — Thu, 11 Sep 2008 19:01:43 GMT

Hi Damian ,

Good suggestion to do a few posts or an article about hosting.

Versioning long running workfows - The Problem Solver

Versioning long running workfows - The Problem Solver — Thu, 11 Sep 2008 18:57:12 GMT

Pingback from Versioning long running workfows - The Problem Solver

Versioning long running workflows part 2

The Problem Solver — Thu, 11 Sep 2008 18:53:13 GMT

Part 1 Part 2 In my previous post I demonstrated how to keep multiple versions of an assembly around

re: Versioning long running workfows

Damian — Thu, 11 Sep 2008 13:25:35 GMT

Hi,

Interesting read and fetched back a few memories.

I put a system together last year when Windows WF was pretty much just released. I hit all sorts of problems with the versioning exceptions when I had to make tweaks to the workflow during testing, but didnt realise exactly why at the time. As there were very few resources around to help me it was a case of having to roll my sleeves up and get under the covers to fully understand what was going on.

It wasnt until i had to make some further changes to the system once it was up and running that i fully got to grips with how the workflow runtime loaded the type for each instance. My first impression was that the workflow item worked its way around the workflow so it didnt matter if you changed the workflow it would just work using the latest version - but this isnt the case. Each instance is a copy of the workflow in a certain way of thinking.

How i finished up getting around it was slightly different to yours as i didnt realise you could do the things you have with the web.config and setting references to assemblies.

What i thought i needed to do was create a new copy of the workflow (at design time) and deploy both versions. This was fine but the next issue i had was how do i copy a workflow and make some changes. Heindsight says this was a bad move but it didnt jump out at me at first. Anyway.. I ended up copying the workflow xaml xml and changing the xaml to a new type - V2. And this actually worked!

Now i had old and new versions of the workflow and could make my changes and deploy.

The next issue i came across was code that was hooked into the workflow, i.e. any services/classes that made use of the workflow. You had to change the code to tell it what version of workflow to create, that was easy but then if you had referred to the workflow at any point in your classes, and this had been removed/changed then it would obviously break.

Now i have more experience in everything .net, not just wwf i plan to revisit wwf and the issues above - so i shall keep an eye on your blog with interest on your next article.

As an aside ive not used wwf in a project since as i found the hosting part a large amount of work as i was hosting in IIS and i had a lot of considerations to think about - threading etc. It is this that has put me off using it more as i think its a fantastic tool. I am now about to look at sharepoint and how it uses the WF.

Also id like to learn more about hosting mutliple types of workflow for multiple projects i.e. easier re-use and a single host deployment. This would be really neat for what i would like to do with workflow.