Thursday, September 11, 2008

Work Item customization tidbits: customization process (part 10 of X)

In the previous post I have talked about the tools to modify Work Item type definitions. Today I’d like to relate to overall process of changing WIT definitions using those tools.

Are you sure that all of thirty Team Projects have the same WI definitions? How do you propagate the changes across project templates or live projects? How do you ensure that the latest change to WI is working? If you have definite answers to those questions, then you have something that may be nicknamed “process”; otherwise you are living on borrowed time and the disaster is waiting to happen.

Let me start with the development environment set up for Work Item type customization. Yes, that’s correct – authoring definitions in XML is not different from traditional writing software. If anything, it is easier to cause large scale problem across your company infrastructure with bad WI type than with custom developed tools (imagine as an example, that new bug definition cannot be saved due to the flaw in WIT logic, or bug cannot be closed, or the automatically update field values are not updated, and then project those examples on X, XX or XXX users environment).

The first principle of WI customization – never develop or deploy at the production server; have it first in the test environment. The easiest way to have test environment is to set up a Virtual PC image (or other virtual image) to work with; the hard thing with this approach being maintaining the image in sync with your production environment (unless you copy production environment into virtual image as needed and use it as your test environment; this approach is the best one when you have appropriate virtualization technology and hardware).

The second principle of WI customization – always verify that changed WI type logic does not break the existing data. That’s why I emphasized above the importance of test environment reflecting the production data; you must have the data you can test with. One frequent example of “breaking” customization is making certain previously obscure and not widely used field mandatory – suddenly every user saving existing work item is faced with updating that field.

And lastly, test custom WI type the same way you test the software. If you have specified twenty states and transitions between those states and defined conditional logic based on state transitions, now you have to achieve high “code coverage” on your definitions. It is worth to keep the future testing burden in mind when making implementation decisions. The testing become even more important if you choose to implement custom controls; in that case you actually develop custom code that needs to be tested and entails integration & deployment testing for your work item template.

Another important aspect of development process is version control. Make sure that every customized project template or WI type is stored in version control; that assures that rolling back changes or tracking changes history is possible and easy. Establishing version control repository update as a necessary step for production deployment also helps in fighting the temptation of committing changes directly to production environment (updating WI types online is a very dangerous feature of Process Template Editor; I’d recommend always using PTE in conjunction with version control and XML files).

Once the definitions are stored in version control repository, it is also easy to script automatic deployment of changed WIT across live Team Projects. I am talking about scenario where same change needs to be propagated across several Team Projects; if you use script (and store it in version control repository) you can document all changes performed and make sure that all required projects are updated.

And finally, very important aspect of customization is human factor. Theoretically, everyone with TFS Admin or Project Admin permissions may run witimport and update Work Item definitions (or use Process Template Editor to perform changes in UI). I’d strongly advise against set up where Work Item customization is performed by every team independently; for the reasons above custom work items development (as any software development) requires certain level of dedication and expertise. In the very least, I’d assign several persons to review changes prior to being deployed to production; after all, the database is shared between all teams.

To summarize, WIT customization process principles are:

  • Always perform development/initial deployment in the test environment
  • Make sure test environment have WI database similar/identical to production environment
  • Test custom WI types as you would test your software
  • Use version control on process templates and WI types; never deploy a definition that is not stored in repository first
  • Automate and document changes deployment
  • Establish clear roles and responsibilities

The overall process may seem cumbersome, too time-consuming and paranoid, but compare that with your software development. Software is not released untested, using appropriate test environment is paramount, developers need to have certain qualification etc. Why would Work Item customization be different? After all, it directly affects your daily development process and its efficiency.

Related posts:
- Work Item Customization: customization tools (part 9)
- Work Item Customization: special fields (part 8)
- Work Item Customization: fields maintenance (part 7)
- Work Item Customization: global lists (part 6)
- Work Item Customization: system fields (part 5)
- Work Item Customization: user interface (part 4)
- Work Item Customization: state transitions (part 3)
- Work Item Customization: conditional field behavior (part 2)
- Work Item Customization: fields definition (part 1)


Anonymous said...

I am wondering if you have a strategy to handle the updated of WI that use the IntegrationBuild field on existing team project.
Since this has the global list hardcoded by team project, do you make your changes individually on each team project?


eugenez said...

I have wrote a general post on that ( Specifically, talking about IntegrationBuild - I tend to keep one copy per all Team Projects with releated WIT, and remove the reference to global list altogether.
TFS will always add the list in SUGGESTEDVALUES (if it is not there)after build is performed.

Does that make sense to you?