Converting from CVS to Subversion?
Bob Bobbinson asks: "I'm currently looking to convert my workplace's CVS repository over to Subversion. The main issue I'm having at the moment before I can commence a roll-out is how we are currently using tags, and sticky tags. The project is a website and we have two tags which are used to put changes from the main trunk live (internally, and externally). All development is committed to the main branch, and when we want a change to go live we move the two 'live' tags to that current version. The live servers are both sticky tagged to these tags, so when we run an update on these servers they will only update to the version that the 'live' tags refer to. Currently I haven't found a satisfactory way to replicate this in Subversion, as moving tags, and updating on separate servers seems to be quite kludgy i.e. need to remove current tagged version from tag, then copy from the main branch over to the tag, then update this on the live server. So I'm trying to look for an alternative way to implement this staggered releasing of code live, and maintaining the ability to see what versions of files constitute what is live. Any ideas?"
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Evan
"$30 for the One True Ring. $10 each additional ring!" -- JRR "Bob" Tolkien
Subversion doesn't support "tagging" like you call it. There are constant of posts the subversion mailing lists about this. 90% of them are ignored, and a few get responses. They prefer to use their branching concept.
This is a case where the authors of Subversion are trying to force their philosphy of how to use version control on the users. I understand that: It is nice when your users are using the software the way that yoy think is best. But that isn't always possible, and they've removed a feature that is common to 90% of all source control systems.
That makes it very hard to migrate to Subversion. There are many build tools, developer's brains, and business procedures that depend on the concept of tagging. Their arguments against it only take into account one side of things. And unfortunately, it has become more of a holy war with the developers ignoring legitimate reasons to support it rather than address them. I really hope this changes, or I fear Subversion will never gain the "critical mass" that CVS has.
With that complaint out of the way, you can somewhat do what you want with two ways. One is to use a branch instead of a tag, and have some way to identify which branch is the "live" branch. A text file. A custom field on one of the files. A rule like "live-###" where you take the largest number. These are your best bet.
If you use a system where you have a large hierarchy, and you cannot deal with all those branches showing up on the tree (it can get really messy) than you can delete old branches, or move them elsewhere. If that's not possible, you are SOL, and Subversion won't work for you.