SVN

Rahul Tripathi

What is version control?Version management allows you to control and monitor

changes to filesWhat 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

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)

subversion conceptscheckout – 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 repositoryI’ve made changes, how do I send them to the group?

update – update all files with latest changesOther people made changes, how do I get them?

tag / branch – label a “release”I want to “turn in” a set of files

Creating a new repositoryCommand 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 SCPluginAdds commands to right-click menu in Finder

GUI Windows Tortoise SVNAdds commands to right-click menu in Explorer

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 statusany changes since revision n?

(resolve conflicts)

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

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...

Revision numbers

0 1 2 3

Revision number is

increased for every

transaction that

changes the repository.

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 ControlRead / write permission for users and groups

Permissions can apply to repo, directory, or file

Loggingauthor of the change

date of the change

reason for the change

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

(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.

(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.

(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.)

Merging

Merging from a Branch

Merge Tracking

Best Practices

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

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 branchname

1)The Subversion “merge”-command.

2)The revision in which we created the branch (267) and HEAD

3) for the complete branch.

4)The branch-name you like to merge into your current

5) working copy.

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 branchname

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

5) working copy.

Merge From a Branch via CLI

Extract the start point of the branch via CLI:

Merge From a Branch via CLI

Merging of a branch via CLI:

Merge From a Branch via TortoiseSVN

Merging of a branch via TortoiseSVN:

Merge From a Branch via TortoiseSVN

Merging of a branch via TortoiseSVN:

Merge From a Branch via TortoiseSVN

Merging of a branch via TortoiseSVN:

Merge Tracking

Merge tracking:

•Subversion does not 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.

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

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

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.

Feature Branches

•Separation by features (one branch each).

Feature 2

Main line

Feature 1

Thank You