Version Control and Subversion. Dr Paul Tennent

Transcription

1 Version Control and Subversion Dr Paul Tennent

2 Outline Housekeeping What is Version Control? Why use it? Using Subversion (SVN)

3 Housekeeping You know where to find everything The handbook You should now appoint a project manager. A couple of groups have notified me and I have given this user admin powers over their group site. The rest of you need to do so asap. You will be using indefero, which supports SVN. You must use SVN for your project.

4 Some of you think you re clever You don t want to use SVN! You re using facebook/ /skype for project management. That s dumb. Don t do that. You want to use GIT! it s the new hotness! True git is lovely, but its just easier if you all use the same system, especially when it comes to judging for prizes, and you want prizes yes? The system is set up for SVN and it does everything you need. But the handbook says we can use whatever version system we want? True, but only because I haven t updated that bit. Have you seen the handbook? It s massive!

5 So where is the code? The magical wonderland is here: Let s take a look.

6 What is Version Control? Alphabet Soup VCS, CVS, SVN, RCS A versioned backup system Restore project to a previous, working state A synchronized control system You can t edit the same files I am editing Well, not without making sure it works

7 Intelligent Backups Reverse-Delta format Compression Scheme Stores only differences (diff, patch) Most Recent Version is fastest retrieval Applies patches to get old versions Attributes Who to blame / give credit Named Versions

8 Synchronized Control One person can edit a file at a time Check-out/Check-in Model Nobody actually uses that (SourceSafe) Dangling Check-out Check-in / Merge Model Make your changes Fix Conflicts Fork Model

9 Subversion Specifics Subversion fixes CVS problems Moving files to different directories Atomic commits Versioned Metadata

10 Why? Can you think of any reason why not?

11 Typical Subversion Uses Create a repository (once) Import or Checkout repository (once) Update and Checkin Merge Label

12 Create a Repository Determine Structure Determine Permissions

13 Import or Checkout Import - I have the files and I want to put them into the initial repository Checkout - I want to start working on an existing repository

14 Update and Check-in Update - Updates the local files to match the central repository Check-in - Update the central repository to match your local files Always update before checking in (svn enforces this) Always test with the latest update before checking in (not enforced)

15 Merge We both update the same file at the same time. What happens? Update tells me there is a conflict You checked yours in first I have to merge the two updates together. Before checking in

16 Label a Version Interim Releases AKA - Hey, this one works! How do you maintain releases?

17 Infrequent Uses Blame Fork Roll back

18 Example Uses Svn help svn help <command> svn checkout: svn checkout \ svn add foo.c svn ci -m Program now cures cancer svn resolved conflictedfile.cpp

19 Interaction with SVN Via command line tools Via some third party tool Eg. TortoiseSVN on windows Via IDE Eg. Eclipse Which should I use? Do you want to look like a cool hacker and then *$ & up your repository? Use the command line Do you want to work like a normal person? Use Tortoise or an IDE plugin

20 Additional Help The Subversion book The Subversion website Tortoise svn client (Windows)

21 Remember Deadline for having your indefero site up and running is 7 th of November. Doesn t need to be vast. Should have a directory structure in place, a good project description etc. Have a look at some of last years projects for inspiration.