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

[Mike Ralphson <mike.ralphson@gmail.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