How would you implement an auto-update for a standalone PHP project using GitHub?

Question

My project is a collection of PHP scripts using MySQL as a database and needs to be installed locally using WAMP/LAMP/MAMP.

Previously I've been sending the users a link to a zipped archive and having them overwrite it, but since I took the plunge to GitHub, I've realized that there are far better ways; namely Service Hooks in GitHub. However, this would work fine as long as I don't alter the database in any way, which is a good possibility.

I've been toying with the idea of how I would implement this, but I can't find a clear solution. So far I've concluded with that I need to have a directory (say update/) which contains .sql files for each update. The PHP script will then check said directory for a file corresponding with the new version number (not sure how I will define a version number; I was thinking of using the commit ID, but that won't be available until after the commit, so...).

I would love some input on this!

Answer 1

Here's how I would tackle this (not the most elegant or performant):

1. Add a flag in the DB with a version number
2. Add a min-version number in your DB layer PHP file
3. Check that the DB version is greater than the min-version
   • If it is: continue about your business
   • Else: Run the PHP file in update/ which would have a series of ALTER TABLE commands to be run on the DB server
     • Update the min-version number in the DB to the latest number
4. All done

Alternately instead of querying the DB you can have a file which is generated by your DB interface PHP file (and ignored with .gitignore) which you can just as above.