Version control,Advantages & disadvantages of GIT,GIT basics,Subversion TortoiseSVN, How to use SVN,Rules on using SVN

2. Content
 Version control
 Advantages & disadvantages of GIT
 GIT basics
 Subversion
 TortoiseSVN
 How to use SVN
 Rules on using SVN
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3. Version Control
 Version control (or revision control, or source control) is all
about managing multiple versions of documents,
programs, web sites, etc.
Some well-known version control systems are CVS, Subversion,
Mercurial, and Git.
Distributed systems like Mercurial and Git are newer and are
gradually replacing centralized systems like
CVS and Subversion.
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4. Local Version Control
 Local version-control method of choice is to copy files
into another directory(perhaps a time-stamped directory, if
they’re clever).
This approach is very common because it is so simple, but
it is also incredibly error prone.
 Ex :-
• RCS
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5. Local Version Control5

6. Centralized Version Control
 Traditional version control system.
• Server with database
• Clients have a working version
 Challenges
• Multi-developer conflicts
• Client/server communication
 Ex :-
• CVS
• Subversion
• Visual source safe
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7. Centralized Version Control7

8. Distributed Version Control
 Authoritative server by convention only.
 Every working checkout is a repository.
 Get version control even when detached.
 Backups are trivial.
 Ex :-
• Mercurial
• BitKeeper
• Darcs
• Bazaar
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9. Distributed Version Control9

10. Advantages of GIT
 Resilience
• No one repository has more data than any other
 Speed
• Very fast operations compared to other VCS (I’m
looking at you CVS and Subversion)
 Space
• Compression can be done across repository not just per
file
• Minimizes local size as well as push/pull data transfers
 Simplicity
• Object model is very simple
 Large user base with robust tools
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11. Disadvantages of GIT
 Definite learning curve, especially for those used to
centralized systems.
• Can sometimes seem overwhelming to learn
 Conceptual difference
 Huge amount of commends
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12. GIT Basics
 Storing data as changes to a base version
of each file.
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13.  Storing data as snapshots of the project over
time.
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14.  Working directory,staging area, and Git directory.
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15. Introduce yourself to GIT
 Enter these lines (with appropriate changes):
• git config --global user.name "John Smith"
• git config --global user.email
jsmith@seas.upenn.edu
 You only need to do this once.
 If you want to use a different name/email address for a
particular project, you can change it for just that project.
• cd to the project directory.
• Use the above commands, but leave out the --global
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16. Create and fill a repository
 cd to the project directory you want to use.
 Type in git init
• This creates the repository (a directory named .git).
• You seldom (if ever) need to look inside this directory.
 Type in git add
• The period at the end is part of this command!
• Period means “this directory”.
• This adds all your current files to the repository.
 Type in git commit –m "Initial commit“
• You can use a different commit message, if you like.
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17. Clone a repository from elsewhere
 git clone URL
 git clone URL mypath
• These make an exact copy of the repository at the
given URL.
 git clone git://github.com/rest_of_path/file.git
• Github is the most popular (free) public repository.
 All repositories are equal,
• But you can treat some particular repository (such as
one on Github) as the “master” directory.
 Typically, each team member works in his/her own
repository, and “merges” with other repositories as
appropriate.
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18. Making commits
 If you create new files and/or folders, they are not tracked by
Git unless you ask it to do so.
• git add newFile1 newFolder1 newFolder2 newFile2
 Committing makes a “snapshot” of everything being tracked
into your repository.
• A message telling what you have done is required
• git commit –m “Uncrevulated the conundrum bar”
• git commit
 This version opens an editor for you the enter the
message.
 To finish, save and quit the editor.
 Format of the commit message.
• One line containing the complete summary.
• If more than one line, the second line must be blank.
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19. Choose an editor
When you “commit,” git will require you to type in a commit
message.
For longer commit messages, you will use an editor.
The default editor is probably vim .
To change the default editor:
• git config --global core.editor /path/to/editor
You may also want to turn on colors:
• git config --global color.ui auto
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20. Typical workflow
 git pull remote_repository
• Get changes from a remote repository and merge them
into your own repository.
 git status
• See what Git thinks is going on.
• Use this frequently!
 Work on your files (remember to add any new ones).
 git commit –m “What I did”
 git push
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21. Multiple versions
Initial commit
Second commit
Third commit
Bob gets a copy
Fourth commit
Merge
Bob’s commit
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22.  Developed in 2000 and 2001 (by CollabNet,
Inc.)
to replace CVS and its shortcomings
• Subversion is free
• Subversion is open-source
• Subversion operates across a network
• Subversion handles any types of files,
documents, or directories
• Subversion requires administrative
support
What is subversion22

23.  On its own, Subversion is command-line driven
• UNIX:
• MS-DOS:
 Numerous GUIs have been built on top of SVN
• TortoiseSVN
• VisualSVN
• XCode (Mac OS X)
Using Subversion
http://tortoisesvn.net/
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24. TortoiseSVN is
• Open-source (free)
• Integrated directly
into Windows Explorer
• Usable with any development environment
TortoiseSVN
http://tortoisesvn.net/
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25. Open source application – download it from
• http://tortoisesvn.net/downloads
After the installation a new
option appears in the menu when
 you right click on a folder.
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26.  Checkout:
• Receives a copy of an entire project from the
SVN server.
• (Source files, project & make files, resource files,
etc.).
 Update:
• Receives copies of individual files or folders on
the server and merges them with your current
copy (locally).
How to use SVN26

27.  Commit:
• Sends an updated file (your local copy) to the
SVN server where.
• It is incorporated into the original project
database;
a new version number is assigned not the entire
project.
 Add:
• Notifies SVN of a new file or folder that needs to
be added to the existing project (only if SVN is
aware of a file, can you commit the file).
How to use SVN Cont.27

28. Right click in the folder you want to check out
into
Select SVN Checkout…
How to checkout28

29.  URL of repository:
http://svn.cs.wayne.edu/svn/csc4111w11/
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30. Enter the user name and password:
• Your accessID (xx1234) and the same
password you use for Pipeline/Blackboard
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31. • Select the project you want to download:
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32.  If you have a set of files checked out and
would like to update them to the most
recent version of files in the repository, use the
update command.
 If there are newer files in the repository, they will
overwrite any files you have locally, if you
haven’t changed them.
 TortoiseSVN can merge some files on its own,
but may tell you there are conflicts with others.
 If a file has a conflict use diff.
Update32

33. How to update
 Right click on the file, folder or project you want to
update and choose SVN Update
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34.  Once you have added, deleted, or changed
files or directories, you can then commit those
changes to the repository.
 Before committing you should always update.
 The safest way to commit, is to diff your project
before you commit.
 Always check your project out after a commit
and make sure it compiles.
Commit34

35.  All commits need to be commented.
 If you forget to comment, make a trivial change
to a file and commit adding in your comment
that it applies to the previous commit.
Commit Comments35

36.  Include:
• Your Name
• The type of commit (Change, Bug Fix, …)
• What the commit does (Adds ToolTip dialog …)
• Any other important details
 Don’t include:
• The names of the files (The log will have them)
• The date or time
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37. How to commit
 Right click on the file, folder or project you
want to update and choose SVN
Commit…
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38.  Right click on the file you want to diff.
 Select Diff, this will compare your file to the most
recent (Head) version on the repository. In a
new window.
How to Diff38

39. If just a word changed, it will be in red on one
side yellow on the other
You can use the green arrows to navigate
through the differences.
Diff - How to solve conflicts39

40. If lines were added/deleted one side will have
gray the other yellow.
The Edit menu has options to help you combine
the files.
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41.  Before you commit make sure you add the file
into the repository
 After you add - commit
Adding new files41

42.  If your commit breaks the baseline.
 Update your local copy
 Check out the last good version
 Commit this version
If you make a bad commit42

43.  Carefully test your code before committing
 Before committing, perform an update on the
whole source code directory, and then retest
 Always commit only the individual files you
modified, not the entire directory
 When adding new files to the existing source
code, always perform SVN Add and then SVN
Commit
 When you have conflicts, contact the
teammates which modified that file and try to
solve the conflicts together to avoid damages.
Rules on using SVN43

44.  Do not share your login and password – you are
responsible for all changes made with your ID
 Do not check out projects of other groups !!!
 If you check in modifications to the project of
other group you might be responsible for that
 If you do not understand something, please ask
GTA before doing that
 If you do not like a client that we’re suggesting
you to use, you’re free to use any other
available SVN client (but please notify me and
write a couple of lines explaining why)
44

45.  www.powershow.com/view4/456743
OGRkM/Version_Control_using_Subversion_SVN_po
werpoint_ppt_presentation.
 https://www.google.com/search?
q=souce+control&ie=utf-8&oe=utf-
8#q=source+control+svn+ppt.
 http://www.powershow.com/view1/7d30b-
ZDc1Z/Version_Control_using_Subversion_SVN_pow
erpoint_ppt_presentation.
 “Version control with git”, Jon Leoliger, O'Reilly
2009.
 “Pro Git”,2nd
Edition, Scott Chacon, Ben Straub.
References45