Re: How to move users from SEU (AS400) to Git?

From: Mike Ralphson <mike.ralphson@gmail.com>
Date: May 12, 2009, 16:40 UTC
Message-ID: <e2b179460905120940u2d87a591kefbdf659e1badd0c@mail.gmail.com>
In-Reply-To: <1CA7E776-B216-4AA5-BFE0-63C0B066980D@npcinternational.com>

2009/5/12 Jon Brisbin <jon.brisbin@npcinternational.com>:

> Our development manager was evaluating transitioning our AS400 department to
> IBM Rational for the RPG programmers, who currently use SEU for all their
> editing and source code control.

+1 everything Shawn and Andreas said, but there are other practical issues beyond developer mindset.

(see http://article.gmane.org/gmane.comp.version-control.git/117755 for my context)

I'm not familiar with the AS400 or SEU but do developers currently have a complete copy of the tree to themselves, or do they only check out the files they're editing?

I'm not sure what Rational Developer is likely to want to do in terms of getting the edited files back to the AS400 (assuming it supports that directly). Are you planning to run (j)git on the AS400 or have another step to get the code from a central git repo back to the AS400(s)?

Is any deployment done to a test server? Is there a release process you need to integrate with?

Our devs expect their changes to go live at midnight after they 'release' them. Are there similar assumptions for you?

They also expect to see everyone else's changes (to all the source files they're *not* working on) as soon as they go live, without having to pull them. Madness, sure, but it's the kind of madness they happen to want.

Previously, no-one would have had to worry about merging / integrating (unless locks were broken). Someone (possibly everyone) now has to do this.

Unless developers have an AS400 at home, or a very funky emulator on their laptop, many of the distributed benefits of git are probably going to be of no use to you.

You probably need to address what concrete benefits remain and see if you *want* to try and sell them.

Local / feature branches, ease of moving work and history between developers, speed, repository size, repository resilience, usable tags, immutable history... All of those might still apply as wins in a centralised / minimal-merging environment.

You may also want to find out if IBM can point you at a reference site for Clearcase (presumably?) on the AS400 in conjunction with Rational Developer on pcs. It may be so bad and so different to what they have now, that you can push git (with a bit of scripting around it) as actually more similar to their current workflow. 8-)

Mike