What is svn? how svn works ? diagram of SVN ? Merging with SVN ? Conflict With SVN ? Checkout and Checkin ,update ,branch , tags ? what is version control "? SVN file directory ? Directories locked in Tags ?

1. Subversion
SVN
Md. Maidul Islam

2. What is version control?

Version management allows you to control and monitor
changes to files
− What changes were made?
− Revert to pervious versions
− When were changes made
− What code was present in release 2.7?

Earliest tools were around 1972 (SCCS)

Older tools – RCS, CVS, Microsoft Source Safe, PVCS
Version Manager, etc…

Current tools – Subversion, Mercurial, Git, Bazaar

3. We will use subversion (svn)

Why?

Because it’s popular

It’s well supported
− IDEs - Netbeans, Eclipse
− Numerous GUI tools
− Command line
− XP Dev has support for it (you will use this for your semester
projects)

4. subversion concepts

checkout – get a local copy of the files
− I have no files yet, how do I get them?

add – add a new file into the repository
− I created a new file and want to check it in

commit – send locally modified files to the repository
− I’ve made changes, how do I send them to the group?

update – update all files with latest changes
− Other people made changes, how do I get them?

tag / branch – label a “release”
− I want to “turn in” a set of files

5. Creating a new repository

Command Line:
− Open command prompt
− Go to a directory where you want your files to be stored
− svn checkout <<location>>/svn/<<your project>>/

GUI Mac OSX SCPlugin
− Adds commands to right-click menu in Finder

GUI Windows Tortoise SVN
− Adds commands to right-click menu in Explorer

6. How to Use Version Control
checkout (first time)
(do some work, test)
update
commit
(do more work, test)
serverclient
send current revision ( n )
update your local copy with any
changes in the repo.
save your changes and log entry
check status
any changes since revision n?
(resolve conflicts)

7. tags
branches
trunk
Project 1
Root
Project 2
Subversion Repository Layout
tags
branches
trunk
tags
trunk
Project 1
Repository parent dir
Project 2
tags
trunk
One repository, many projects One project per repository
branches
branches

8. Subversion "repository"

Typically one "repository" per project.

Server can have an unlimited number of
"repositories".
/var/svn/kuclock
revision 1
(initial repo structure)
revision 2
revision 3
revision 3:
 content diffs
 author
 date
 reason for change (comment)
revision 4
"KUClock" Project Repository
revision 2:
 initial project check-in
 ...etc...

9. Revision numbers
0 1 2 3
Revision number is
increased for every
transaction that
changes the repository.

10. Properties of a Repository

History of all changes to files and directories.
− you can recover any previous version of a file
− remembers "moved" and "deleted" files

Access Control
− Read / write permission for users and groups
− Permissions can apply to repo, directory, or file

Logging
− author of the change
− date of the change
− reason for the change

11. URLs and Protocols
http://myhost.com:port/path/to/repository
Protocol:
svn
svn+ssh
http
https
file
Host name or
IP address
127.0.0.1
localhost
host:8443
optional port
number
Repository
relative
path

12. (1) Check Out using TortoiseSVN
Using Windows Explorer, right-click in a directory.
If not sure of path to check-out
then use Repo-browser first.
In Repo-browser, right-click on
folder or file you want to check-
out.

13. (1) Check out using Eclipse
Many ways to do it. Here is a simple way:
1. Switch to "SVN Repository Exploring Mode".
2. Right click and choose
New => Repository Location
3. Enter URL and (optional)
authentication info.

14. (1) Check out using Eclipse

Now you can browse the repository.

Choose the part you want to check-out
(usually "trunk")

Right click and choose "Check Out as..."
("Check Out as..." gives you a chance to
change local project name if you want.)

15. Merging
 Merging from a Branch
 Merge Tracking
 Best Practices

16. Merging From a Branch
• What’s with the bug you've fixed on the bug-
fix-branch?
• What about your current development?
• You have to merge the
changes made in the branch
back to the main line.
RELEASE 1.0.0
BUGFIX_BRANCH
Merge back
267
RELEASE
1.0.1

17. Merge From a Branch via CLI
You can merge the changes from the branch
into your current working copy with the
following command:
svn merge -r 267:HEAD branchnamebranchname
(1) The Subversion “merge”-command.
(2) The revision in which we created the branch (267) and HEAD
for the complete branch.
(3) The branch-name you like to merge into your current
working copy.

18. Merge From a Branch via CLI
You can find the revision number when the
branch was created using the command:
svn log --verbose --stop-on-copy branchnamebranchname
(1) The Subversion “log”-command.
(2) Print out much information (verbose).
(3) Stop the log-output at the revision the branch was copied.
(4) The branch-name you like to merge into your current
working copy.

19. Merge From a Branch via CLI
Extract the start point of the branch via CLI:

20. Merge From a Branch via CLI
Merging of a branch via CLI:

21. Merge From a Branch via
TortoiseSVN
Merging of a branch via TortoiseSVN:

22. Merge From a Branch via
TortoiseSVN
Merging of a branch via TortoiseSVN:

23. Merge From a Branch via
TortoiseSVN
Merging of a branch via TortoiseSVN:

24. Merge Tracking
Merge tracking:
• Subversion does notnot have any function to
track merges that have already been done,
i.e., to prevent you to merge a branch a
second time.
• You have to do it yourself!
•Example: after merging, create a README-
merged file in the branch stating that it was
merged into trunk revision r99.

25. From the technical view branch and tag are the
same.
BUT:
• The intention of a tag is that it should be used as
read-only area whereas a branch is used to
continue development (interim code, bug-fixing,
release candidate etc.).
• Technically you can use a tag to continue
development and check in etc. but you shouldn’t
do it.
• So in other words the difference between a tag
and a branch is just an agreement.
Merge Warning

26. Developer Branches
• Separation of team members can be realized
with branches.
• One branch per team member or several
members on a branch - the decision is
based on the size of the teams.
Member 2
Main line
Member 1

27. Developer Branches
• Advantages using branches for team work:
•No changes during development on the main line
needed => Code stability.
•Every team member can work in its own environment.
• Disadvantages:
•Sometimes the mainline and the branch will diverge if
the branch lives too long.

28. Feature Branches
• Separation by features (one branch each).
Feature 2
Main line
Feature 1

29. Thank You