Introduction
[http://subversion.tigris.org/ Subversion] aka SVN [http://packages.debian.org/subversion (Debian package)] is a version control system that is a compelling replacement for CVS in the open source community.
It has many features and improvements with respect to CVS, but most important ones are:
- rename support
- truly atomic commits
- directory and file meta-data are versioned
- efficient handling of binary files
- internal commands resemble a lot with CVS' commands
Basic commands and usage
Projects must start: svn import
Each project must start its life in SVN by an import command. It is recomended that each project should have a structure that would allow branching and tagging in a convenient manner; see the chapter [http://svnbook.red-bean.com/nightly/en/svn.reposadmin.projects.html#svn.reposadmin.projects.chooselayout choosing repository layout] more info.
svn import -m "New import" localprojdir svn+ssh://svn.debian.org/svn/aliothproj/path/in/project/repository
After the initial import, the surce just used for the import should be removed and a checked out version should be used for further modifications.
Summary:
- Needs:
- created repository
- (network) access to repository
- Moreinfo:
[http://svnbook.red-bean.com/nightly/en/svn.ref.svn.c.import.html svn import]
[http://svnbook.red-bean.com/nightly/en/svn.reposadmin.projects.html#svn.reposadmin.projects.chooselayout Choosing repository layout]
Getting a working copy: svn checkout
Once the project is in subversion, a developer can get a copy of it by using the checkout command. This is necessary so subversion can track your local changes. Usualy one would want to get the most recent version from trunk, but in some cases one would want to check out a branch. Checking out a branch is no different from checking out from trunk, one will use the svn checkout command.
svn checkout svn+ssh://developer@svn.debian.org/svn/aliothproj/trunk
Now you can make your modifications to the checked out directory.
Note: Checking out a single file is not possible, only directories can be checked out.
Summary:
- Needs:
- working repository
- (network) access to repository
- Moreinfo:
[http://svnbook.red-bean.com/nightly/en/svn.ref.svn.c.checkout.html svn checkout]
[http://svnbook.red-bean.com/nightly/en/svn.tour.initial.html initial checkout]
Checking status: svn status
You made modification, but you want to see a summary of the local copy's status.
svn status
Summary:
- Needs:
- checked out copy
- Moreinfo:
[http://svnbook.red-bean.com/nightly/en/svn.ref.svn.c.status.html svn status]
[http://svnbook.red-bean.com/nightly/en/svn.tour.cycle.html#svn.tour.cycle.examine.status the meaning of the letters on the first column]
Checking modifications: svn diff
You have found out that a file has some mofications since it was synced with the repository. Seeing the contents of the change can be done with svn diff.
svn diff
- Needs:
- checked out copy
- Moreinfo:
Saving your changes: svn commit
You have seen what changed and you decide is time to make your changes public to do that, use svn commit
svn commit -m "made foo changes to current directory"
If no parameter is specified, the current directory's (and subdirectories') changes are committed in subversion. The commit can be done also on a "per file" basis by specifing the names of the files/subdirectories to have their changes committed.
svn commit -m "made foo changes to some_modified_file" some_modified_file
Summary:
- Needs:
- working repository
- (network) access to repository
- local changes
- Moreinfo:
[http://svnbook.red-bean.com/nightly/en/svn.ref.svn.c.commit.html svn commit]
[http://svnbook.red-bean.com/nightly/en/svn.tour.cycle.html#svn.tour.cycle.commit commit your changes]
Branching and tagging: svn copy
From time to time it is necessary to isolate a certain snapshots (usualy from trunk) of the project. This might be the case if in a project a release is wanted or a certain feature is to be developed in a branch.
Subversion does not distinguish between copying, tagging and branching and all of them can be accomplished through the usage of the copy command.
svn copy -m "Tag release 0.4" svn+ssh://svn.debian.org/svn/aliothproj/trunk svn+ssh://svn.debian.org/svn/aliothproj/tags/0.4
Summary:
- Needs:
- working repository
- (network) access to repository
- previous reference revision
- Moreinfo:
[http://svnbook.red-bean.com/nightly/en/svn.ref.svn.c.copy.html svn copy]
[http://svnbook.red-bean.com/nightly/en/svn.branchmerge.using.html branching and merging]
Basic work cycle
The SVN book [http://svnbook.red-bean.com/nightly/en/svn.tour.cycle.html describes] very well the basic working cycle; more informations are available [http://svnbook.red-bean.com/nightly/en/svn.tour.cycle.html there].
Tips and tricks
[http://svnbook.red-bean.com/nightly/en/svn.serverconfig.svnserve.html#svn.serverconfig.svnserve.sshauth enabling ssh key access] and using an ssh agent will spare you from enetring a password at each operation that involves the repository; also the user name can be set in settings in ~/.ssh/config, so when issuing commands that require server authentication, it will not be mandatory to insert all needed data (ssh remote port number, username, etc.), because this data is already in ~/.ssh/config
- always tag your releases
- merging regularly the changes from trunk when woring in a branch is a huge help at the time when the branch work will be integrated in trunk
DO NOT fiddle with or remove the contents of the .svn directories!