SVN 用于开发 web 服务器

Question

I've checked other threads about this subject, but nothing really answers my exact question. I'm currently developing a site that updates data on a live web server (usually photos) multiple times daily using a cron and some external data feeds. Additionally, we're about to allow user-submitted data. Now, I want to start using svn because the project is getting big enough where it's starting to get relatively complicated and people are making edits to our code on the live server. I've installed svn for apache and all of the subdomains mentioned below are set up on one server using vhosts. We haven't started using this workflow yet, so if I could get some advice before we start it would be greatly appreciated.

Okay, so I've set up a repository under a subdomain (http://svn.website.com), and checked it out to a development subdomain (http://dev.website.com). I also plan to check out a copy to the live environment (http://www.website.com). The idea is to first develop on the dev subdomain, commit when it's ready to go live, and then svn up to the live environment. I've read the pros and cons between exporting and updating, and updating seems best for this project because we often will commit small tweaks/code changes and exporting seems like overkill. I have also setup the appropriate directives to avoid.svn directory access. Does it sound like I'm on the right track with this? Anything I should be aware of?

If the following is a good way to take care of everything, then we can move onto the second question. The user-submitted data (mainly photos) are being uploaded to the live environment. I have to somehow manage this between the live and dev environment so we can develop with up-to-date user-submitted files. I don't really know the best way to do this...I feel like there's a serious flaw if I were to svn add and svn ci every time a file is submitted. What is the best way to accomplish this?

Answer 1

Sounds like you're growing!

First, I'd question as to whether SVN is really the best choice. My guess is that you know it already, have worked with it, as have others on your team, and you want to stick with it. That's fine, but just an FYI I've used SVN and Git and I found Git generally easier to use, and I would argue that it is becoming more and more commonly used by application developers.

As for your workflow, I used to go through an almost identical process with a large distributed team and it worked fine. Depending on the amount of traffic you get, I might suggest a different production deployment strategy. When you're ready for a new production push, clone into a new directory, labeled perhaps by date or milestone names, and create a new virtual host for that directory. That way, you get a couple benefits:

1. You don't run the risk of having someone access your application and requesting a certain file which is in the process of being updated
2. You can easily revert back to an earlier milestone by simply changing the active production virtual host. Bugs and problems make it out of development regardless of how thoroughly you test, and sometimes they're serious enough to warrant just reverting back to a previous codebase. Of course, schema changes would add complexity to this, but if we're just talking about code this should avoid frantic commit reverts at 2am.

This was suggested by Rasmus Lerdorf at a conference I attended when he was posed nearly the same question you're asking.

As for ensuring developers are working with the most recent fileset, do you really want to do this? If you're processing a serious quantity of images, that's going to take up a lot of hard disk space. Sure with a CDN or other mass storage no big deal, but do you want your developers to have to download 1000 new photos every time they svn up?

If you're dead set on doing this, I'd suggest adding some code within your app for automatically doing an svn add, svn ci when svn status has a certain result (ie, this is a script you could call with cron, or every time new media gets added). You could also check into using svn hooks (git has these as well) to do things like notify you that the repo has been updated.

Hope this helps. I'd strongly discourage including all of the files users upload unless you have a really, really strong reason for doing so. The complexity that's gonna add is gonna be a pain = )

Good luck and welcome to StackOverflow!