Subversion 101: A short introduction to Subversion

A short tour to Subversion, in Vietnamese and English.

1. 2010/10/05 Subversion 101
Nguyen Vu Hung
Version Control::
Subversion 101
Nguyen Vu Hung
[email protected]
2010/10/05

2. 2010/10/05 Subversion 101
Nguyen Vu Hung
Change History
No Author Date Slides Details
1 Vuhung 2010/10/04 All Newly created
2 Vuhung 2010/10/05 - -
3 Vuhung 2011/01/06 All Remove private info

3. 2010/10/05 Subversion 101
Nguyen Vu Hung
Agenda
•Introduction
–The Symptoms
–Revision Control System overview
–Atomic Commits
–Revision Explained
–Svn History
•Overview
–Basic usages
–Architecture
–Components
•Installation
–Server, client

4. 2010/10/05 Subversion 101
Nguyen Vu Hung
Agenda (2)
•IDE integration
•Command comparison
•Workflow
•Staging
•Staging (Debian)
•Repository schema
•Resolve Conflicts
•Basic Commands
–Merging
–Revert
–Update
–Add
–Delete
–copy
–move
–mkdir
–status
–diff
•Tips
•Examing History
•Summary: Basic Commands
•Summary: What svn can do?
•Summary: Terminologies
•Alternatives
•References

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Nguyen Vu Hung
The Symptoms
•You need files in Recycle Bin
•Having more than 2 levels of undo (backup) in a
document
–vet_20100823.sql, vet_20100824.sql, vet_bak.sql,
•Asking someone to send a copy of some files.
•FTP transaction died
•You don’t know what is done yesterday
•It works yesterday, but not today.
–URGENT: roll back
•Failed to manage source code change/merging

6. 2010/10/05 Subversion 101
Nguyen Vu Hung
Revision Control System
Revision control, also known as version control, source control or
software configuration management (SCM), is the management of
changes to documents, programs, and other information stored as
computer files. It is most commonly used in software development, where a
team of people may change the same files. Changes are usually
identified by a number or letter code, termed the "revision number",
"revision level", or simply "revision". For example, an initial set of files is
"revision 1". When the first change is made, the resulting set is "revision 2",
and so on. Each revision is associated with a timestamp and the
person making the change. Revisions can be compared, restored, and
with some types of files, merged.

7. 2010/10/05 Subversion 101
Nguyen Vu Hung
Atomic Commits
–None or entire
•Single Operation
–Revision:per-commit
–No inconsistence in
large commits
–Files within a commit
are grouped
0 1
2 3

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Nguyen Vu Hung
Revision Control system
0 1 2
3
As Atomic Changes
Not just change,
It is change management

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Nguyen Vu Hung
History
•June 2000 - Coding begins.
•August 2001 - Subversion
becomes self-hosting.
•2002 – 1
st
release
•2004 – Feb. Release 1.0.0
•2006 – Sept. Release 1.4.0
•Latest Release: 1.4.6

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Nguyen Vu Hung
Usages
Backing up data
Documentation
Configuration
Management
Distributed
Development
CR 12

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Nguyen Vu Hung
Architecture
Berkley DB
FSFS
Subversion
Repository
Client Interface Repository Interface
GUI client
apps
Commandline
client apps
Client
Library
Working Copy Management
Library
Repository
access
DAV
SVN
Local
Apache
mod_dav
mod_ dav_ svn
svnserve
Internet
(Any TCP/IP Network)
Offline Support
Unix/Linux/Windows/Mac OS X
WebDav Integration
SSL
LDAP

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Nguyen Vu Hung
Subversion Components
svn (this is what you [client] need)
-The command-line client program.
svnadmin
- A tool for creating, tweaking or repairing a
Subversion repository.
svnserve
-A custom standalone server program, runnable as a
daemon process or invokable by SSH; another way
to make your repository available to others over a
network.

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Installation (server)
yum install mod_dav_svn subversion

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Installation (server settings)
[root@vinicorp conf]# cat /etc/httpd/conf.d/subversion.conf
LoadModule dav_svn_module modules/mod_dav_svn.so
LoadModule authz_svn_module modules/mod_authz_svn.so
<Location /svn-repo>
DAV svn
SVNParentPath /svn-repo
# Limit write permission to list of valid users.
<LimitExcept GET PROPFIND OPTIONS REPORT>
# Require SSL connection for password protection.
# SSLRequireSSL
AuthType Basic
AuthName "Vinicorp Subversion Realm"
AuthUserFile /etc/svn-auth-conf
Require valid-user
</LimitExcept>

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Nguyen Vu Hung
Installation (server settings)
[root@vinicorp conf]# head /etc/svn-auth-conf
#vinicorp:pIuFZUS0McheY
hoatran:3cYHbUvT9aV0o
doancuong:0K3C3IdVJD7VY
thuanvd:xJSWLpXNr5/EM
hiennb:GHvHoKOG2E1eI
huyenvtt:FySHeMI9u9uvc
trungdq:MB7kxm/IgGMsY
thuytp:rw68sUTpnVD7M
thangnv:zSoOwCSdqqcLk
phuongdt:o2ZYftrCjq2oM
[root@vinicorp conf]# wc -l /etc/svn-auth-conf
51 /etc/svn-auth-conf

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Nguyen Vu Hung
Installation (server settings)
[root@conf]# head /etc/svn-auth-conf
#xxxxxxxxxx:pIuFZUS0McheY
xxxxxxxxxx:3cYHbUvT9aV0o
xxxxxxxxxx:0K3C3IdVJD7VY
xxxxxxxxxx:xJSWLpXNr5/EM
xxxxxxxxxx:GHvHoKOG2E1eI
xxxxxxxxxx:FySHeMI9u9uvc
xxxxxxxxxx:MB7kxm/IgGMsY
xxxxxxxxxx:rw68sUTpnVD7M
xxxxxxxxxx:zSoOwCSdqqcLk
xxxxxxxxxx:o2ZYftrCjq2oM
[root@conf]# wc -l /etc/svn-auth-conf
51 /etc/svn-auth-conf
Create a repo:
mkdir /svn-repo
Create an user:
htpasswd -c /etc/svn-auth-conf vinicorp

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Nguyen Vu Hung
Installation (server settings)
[root@ svn-repo]# pwd
/svn-repo
[root@ svn-repo]# ls -1
001.Project1
005. Project2
006. Project3

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Nguyen Vu Hung
Installation (server settings)
[root@ svn-repo]# pwd
/svn-repo
[root@ svn-repo]# ls -1
001.Project1
005.Project2
006.Project3
cd /svn-repo
svnadmin create 001.Project1
chown -R apache.apache 001.Project1
service httpd restart

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Nguyen Vu Hung
Installation (client)
•TortoiseSVN (Windows)
•svn/subversion (Unix/Linux)
•svn (Mac OS X)
•RapidSVN (cross-platform)

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Nguyen Vu Hung
IDE integration
•svn + Eclipse = Subclipse
•svn + File Explorer = Tortoisvn
•svn + GUI = Rapid svn
•svn + vim = svn
•Svn + emacs = svn

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Nguyen Vu Hung
Command comparison
•Available subcommands:
• add
• blame
–(praise, annotate, ann)
• cat
• checkout (co)
• cleanup
• commit (ci)
• copy (cp)
• delete
–(del, remove, rm)
• diff (di)
• export
• help (?, h)
• import
• info
• list (ls)
• lock
•
• log
• merge
• mkdir
• move
–(mv, rename, ren)
• propdel (pdel, pd)
• propedit (pedit, pe)
• propget (pget, pg)
• proplist (plist, pl)
• propset (pset, ps)
• resolved
• revert
• status (stat, st)
• switch (sw)
• unlock
• update (up)

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Nguyen Vu Hung
Workflow (admin)
•Create a repository (once)
•Import or Checkout repository (once)
•Update and Checkin
•Merge
•Commit

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User Workflow
•Step 1
–Obtain SVN Repository URL from SVN Admin
–Ex 1: svn://192.168.x.3/svn-repo/0xx.Proj
–Ex 2: http://192.168.x.3/svn-repo/0xx.Proj
•Step 2
–Checkout SVN module (Repository Copy) to local
file system (Working Copy)
•Step 3
–Update, Commit, Branch, Tag etc.,

24. 2010/10/05 Subversion 101
Nguyen Vu Hung
Workflow
Update your working copy
-svn update
Make changes
-svn add
-svn delete
-svn copy
-svn move
Examine your changes
-svn status
-svn diff
Possibly undo some changes
- svn revert
Resolve Conflicts (Merge Others' Changes)
- svn update
- svn resolved
Commit your changes
- svn commit

25. 2010/10/05 Subversion 101
Nguyen Vu Hung
Work flow
svn checkout
svn update
get content
svn add
svn move
svn delete
Make changes
svn status -u
See what was changed
in the repository in the meantime
svn update
Update your local copy
svn diff
svn resolved
Merge your changes
Resolve conflicts
svn commit
Submit your changes
105
100
106
Subversion
Repository

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Branching
branches
trunk
PC
Root
iPhone
PC branch (vuhung)
branches
trunk
Easy to understand
Cheap (a little copy)
Can be deleted/reanimated

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Branching (2)
branches
trunk
001.SPS
Root
HuyDN
HungNT

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Staging
•Staging can be managed via folder structures
tags
Project 1
Root
trunk
Dev
QA
Rel
Development stage (TestServer.biz)
Releases for QA (Test [For the Customer])
Final Releases (ProductionServer.com)

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Nguyen Vu Hung
Real World Example: Debian

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Repository schema
Schema and Access Method
•file:/// direct repository access (on local disk)
•http:/ access via WebDAV protocol to Subversion-aware Apache server
•https:// same as http://, but with SSL encryption.
•svn:// access via custom protocol to an svnserve server
•svn+ssh:// same as svn://, but through an SSH tunnel.

31. 2010/10/05 Subversion 101
Nguyen Vu Hung
Resolve Conflicts
For example, Sally makes changes to the file sandwich.txt in the
repository. Harry has just changed the file in his working copy and
checked it in. Sally updates her working copy before checking in and she
gets a conflict:
$ svn update
C sandwich.txt
Updated to revision 2.
$ ls -1
sandwich.txt
sandwich.txt.mine
sandwich.txt.r1
sandwich.txt.r2
At this point, Subversion will not allow you to commit the file
sandwich.txt until the three temporary files are removed.

32. 2010/10/05 Subversion 101
Nguyen Vu Hung
Resolove Conflicts
•$ svn commit -m "Add a few more things"
•svn: Commit failed (details follow):
•svn: Aborting commit: '/home/vuhung/work/sandwich.txt' remains in conflict
If you get a conflict, you need to do one of three things:
-Merge the conflicted text “by hand” (by examining and editing the conflict markers
within the file).
-Copy one of the temporary files on top of your working file.
-Run svn revert <filename> to throw away all of your local changes.
Once you've resolved the conflict, you need to let Subversion know by running svn
resolved. This removes the three temporary files and Subversion no longer considers the
file to be in a state of conflict.[6]
$ svn resolved sandwich.txt
aResolved conflicted state of 'sandwich.txt'

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Nguyen Vu Hung
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

34. 2010/10/05 Subversion 101
Nguyen Vu Hung
Merge Conflicts by hand
Merging conflicts by
hand can be quite
intimidating the first
time you attempt it,
but with a little
practice, it can
become as easy as
falling off a bike.
Here's an example. Due to a miscommunication, you
and Sally, your collaborator, both edit the file
sandwich.txt at the same time. Sally commits her
changes, and when you go to update your working
copy, you get a conflict and you're going to have to edit
sandwich.txt to resolve the conflicts. First, let's take a
look at the file:
$ cat sandwich.txt
Top piece of bread
Mayonnaise
Lettuce
Tomato
Provolone
<<<<<<< .mine
Salami
Mortadella
Prosciutto
=======
Sauerkraut
Grilled Chicken
>>>>>>> .r2
Creole Mustard
Bottom piece of bread

35. 2010/10/05 Subversion 101
Nguyen Vu Hung
Merging: Revert
Punting: Using svn revert
-If you get a conflict, and upon examination decide that you want to
throw out your changes and start your edits again, just revert your
changes:
$ svn revert sandwich.txt
Reverted 'sandwich.txt'
$ ls sandwich.*
sandwich.txt
-Note that when you revert a conflicted file, you don't have to run svn
resolved.

36. 2010/10/05 Subversion 101
Nguyen Vu Hung
Checkin
•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)

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Nguyen Vu Hung
commit
•svn commit command sends all of your
changes to the repository. When you commit
a change, you need to supply a log message,
describing your change. Your log message
will be attached to the new revision you
create. Log message can be set in command
line using the --message (or -m) switch:
$ svn commit -m "Corrected number of cheese slices."
Sending sandwich.txt
Transmitting file data .
Committed revision 3.

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Nguyen Vu Hung
checkout
$ svn checkout http://192.168.x.3/svn-repo/0xx.Proj
A 0xx.Proj/SourceCode
A 0xx.Proj/Document
…
Checked out revision 1.

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Nguyen Vu Hung
update
•Update - Updates the local files to match the
central repository
–NOTE: Change to the working folder (the local
folder that you have checked out from the
repository into your local file system)
svn update
U SourceCode/care/public/images/basic_title_bg.gif
U SourceCode/care/public/images/btn_search.gif
　Updated to revision 2.

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Nguyen Vu Hung
svn add
•svn add foo
–Schedule file, directory, or
symbolic link foo to be added to
the repository. When you next
commit, foo will become a child
of its parent directory. Note
that if foo is a directory,
everything underneath foo will be
scheduled for addition. If you
only want to add foo itself, pass
the --non-recursive (-N) option.

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Nguyen Vu Hung
svn delete
•svn delete foo
–Schedule file, directory, or ymbolic
link foo to be deleted from the
repository. If foo is a file or
link, it is immediately deleted from
your working copy. If foo is a
directory, it is not deleted, but
Subversion schedules it for
deletion. When you commit your
changes, foo will be removed from
your working copy and the
repository.

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svn copy
•svn copy foo bar
–Create a new item bar as a
duplicate of foo and automatically
schedule bar for addition. When
bar is added to the repository on
the next commit, its copy history
is recorded (as having originally
come from foo). svn copy does not
create intermediate directories.

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Nguyen Vu Hung
svn move
•svn move foo bar
–This command is exactly the same as
running svn copy foo bar; svn delete
foo. That is, bar is scheduled for
addition as a copy of foo, and foo is
scheduled for removal. svn move does
not create intermediate directories.

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Nguyen Vu Hung
svn mkdir
•svn mkdir blort
–This command is exactly the same
as running mkdir blort; svn add
blort. That is, a new directory
named blort is created and
scheduled for addition.

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Nguyen Vu Hung
svn update (2)
Update working copy
-Update all files and directories to the most current version
$svn update
-Go to a particular older revision for all files and directories
$% svn update –r 1345
-I want an even older version of svn-doc.el
$% svn update –r 999 FolderName
Update output and what it means
-U `foo'
File `foo' was (U)pdated (received changes from the server.)
-A `foo'
File or directory `foo' was (A)dded to your working copy.
-D `foo'
File or directory `foo' was (D)eleted from your working copy.
-R `foo'
File or directory `foo' was (R)eplaced in your working copy; that is, `foo' was deleted, and a new item with the same name was
added. While they may have the same name, the repository considers them to be distinct objects with distinct histories.
-G `foo'
File `foo' received new changes, but also had changes of your own to begin with. The changes did not intersect, however, so
Subversion has mer(G)ed the repository's changes into the file without a problem.
-C `foo'
File `foo' received (C)onflicting changes from the server. The changes from the server directly overlap your own changes to the
file. No need to panic, though. This overlap needs to be resolved by a human (you).

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Nguyen Vu Hung
svn status
svn status
-A Daily/20100927/chuyen.txt # file is scheduled for addition
-C Daily/20100824/iPadQA.xl # file has textual conflicts from an update
-D Daily/20100927/chuyen.lrc # file is scheduled for deletion
-M Daily/20100927 # the content in Daily/20100927 has local
modifications
A item
The file, directory, or symbolic link item has been scheduled for addition into the
repository.
C item
The file item is in a state of conflict. That is, changes received from the server during an
update overlap with local changes that you have in your working copy. You must
resolve this conflict before committing your changes to the repository.
D item
The file, directory, or symbolic link item has been scheduled for deletion from the
repository.
M item
The contents of the file item have been modified.

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Nguyen Vu Hung
Svn diff
[vuhung@ 20100927]$ svn diff .
Index: chuyen.lrc
===================================================================
--- chuyen.lrc (revision 166)
+++ chuyen.lrc (working copy)
@@ -5,15 +5,15 @@
[00:15.83]chieu ngoai o, gio khe dua toc em
[00:26.51]Cong cong con duong uon quanh.
-[00:30.71]chieu dao pho, chieu mang chut huong thanh binh
[00:46.72]Thuong anh yeu anh em uoc mo.
-[01:01.23]Uoc mo nho be trong doi
+[01:01.23]Uoc va mo nho be trong doi
[01:16.11]UOc mo cho tinh yeu len hat sac xuan
+[01:16.11]UOc mo cho tinh yeu len hat sac xuan
[01:21.19]Uoc mo la la tren canh
[01:27.07]Nguoc mat thay bao giac mo.
@@ -44,4 +44,4 @@
[03:53.07]??c m? nh? be trong ??i
[03:58.84]Ng??c m?t th?y bao gi?c m?.
-[04:10:10]
\ No newline at end of file
+[04:10:10]

48. 2010/10/05 Subversion 101
Nguyen Vu Hung
Tips
•Commit small
•Commit often
•Comment, comment, comment
•Change set
•svn update (online) vs. svn status (offline)
•svn log: who && what
•svn merge = you + me.
•svn update and test before commit
•Work on local copy
•Solve the conflicts
•Do not commit hidden, un-related, temporary files.

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Examining History
•svn log
•svn diff
•svn history
•svn list

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Summary: Basic Commands
•svn add — Add files, directories, or symbolic links.
•svn copy — Copy a file or directory in a working copy or in the repository.
•svn mkdir — Create a new directory under version control.
•svn delete — Delete an item from a working copy or the repository.
•svn export — Export a clean directory tree.
•svn import — Commit an unversioned file or tree into the repository.
•svn move — Move a file or directory
•svn diff — Display the differences between two paths.
•svn merge — Apply the differences between two sources to a working copy
path.
•svn resolved — Remove “conflicted” state on working copy files or directories.
•svn revert — Undo all local edits.
•svn status — Print the status of working copy files and directories.
•svn update — Update your working copy.
•svn checkout — Check out a working copy from a repository.
•svn commit — Send changes from your working copy to the repository.

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Summary: What svn can do?
•Backup and Restore. Files are saved as they are edited, and you can jump to
any moment in time. Need that file as it was on Feb 23, 2007? No problem.
•Synchronization. Lets people share files and stay up-to-date with the latest
version.
•Short-term undo. Monkeying with a file and messed it up? (That’s just like you,
isn’t it?). Throw away your changes and go back to the “last known good”
version in the database.
•Long-term undo. Sometimes we mess up bad. Suppose you made a change a
year ago, and it had a bug. Jump back to the old version, and see what change
was made that day.
•Track Changes. As files are updated, you can leave messages explaining why
the change happened (stored in the VCS, not the file). This makes it easy to see
how a file is evolving over time, and why.
•Track Ownership. A VCS tags every change with the name of the person who
made it. Helpful for blamestorming giving credit.
•Sandboxing, or insurance against yourself. Making a big change? You can make
temporary changes in an isolated area, test and work out the kinks before
“checking in” your changes.
•Branching and merging. A larger sandbox. You can branch a copy of your
code into a separate area and modify it in isolation (tracking changes
separately). Later, you can merge your work back into the common area.

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Summary: Terminologies (Basic Setup)
•Repository (repo): The database storing the
files.
•Server: The computer storing the repo.
•Client: The computer connecting to the repo.
•Working Set/Working Copy: Your local
directory of files, where you make changes.
•Trunk/Main: The primary location for code in
the repo. Think of code as a family tree —
the trunk is the main line.

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Summary: Terminologies (Basic
Actions )
•Add: Put a file into the repo for the first time, i.e. begin tracking it with
Version Control.
•Revision: What version a file is on (v1, v2, v3, etc.).
•Head: The latest revision in the repo.
•Check out: Download a file from the repo.
•Check in: Upload a file to the repository (if it has changed). The file gets
a new revision number, and people can “check out” the latest one.
•Checkin Message: A short message describing what was changed.
•Changelog/History: A list of changes made to a file since it was created.
•Update/Sync: Synchronize your files with the latest from the repository.
This lets you grab the latest revisions of all files.
•Revert: Throw away your local changes and reload the latest version
from the repository.

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Nguyen Vu Hung
Summary: Terminologies (Advanced Actions)
•Branch: Create a separate copy of a file/folder for private use (bug fixing,
testing, etc). Branch is both a verb (”branch the code”) and a noun (”Which
branch is it in?”).
•Diff/Change/Delta: Finding the differences between two files. Useful for seeing
what changed between revisions.
•Merge (or patch): Apply the changes from one file to another, to bring it up-to-
date. For example, you can merge features from one branch into another. (At
Microsoft this was called Reverse Integrate and Forward Integrate)
•Conflict: When pending changes to a file contradict each other (both changes
cannot be applied).
•Resolve: Fixing the changes that contradict each other and checking in the
correct version.
•Locking: Taking control of a file so nobody else can edit it until you unlock it.
Some version control systems use this to avoid conflicts.
•Breaking the lock: Forcibly unlocking a file so you can edit it. It may be needed if
someone locks a file and goes on vacation (or “calls in sick” the day Halo 3
comes out).
•Check out for edit: Checking out an “editable” version of a file. Some VCSes
have editable files by default, others require an explicit command.

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Nguyen Vu Hung
Alternatives
•Historical
–RCS (Revision Control System)
•Distributed model
–Bazzar (python-based, Canonical supported)
–Git (Perl, C, shell based)
•Open source
–CVS (Concurrent Versions System)
–CSVNT (for Windows [NT])
•Proprietary
–CMVC (Configuration Management Version Control) (IBM)
–Visual Source Safe (Microsoft)
–Visual Studio Team System (Microsoft)

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57. 2010/10/05 Subversion 101
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Version Control::
Subversion 101
Nguyen Vu Hung
[email protected]
2010/10/05

58. 2010/10/05 Subversion 101
Nguyen Vu Hung
References
•Polarion subversion tutorial
•http://www.slideshare.net/intellibitz/subversion-user-guide
•http://www.ericsink.com/scm/source_control.html
•http://betterexplained.com/articles/a-visual-guide-to-version-control/
•Photographer: jscreationzs
http://www.freedigitalphotos.net/images/Browns_and_Creams_g332-
Question_Mark__p17549.html