[[What Is Subversion For|<<]] ... [[SVNKit Architecture|>>]]
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== Subversion repository types ==
Up to now a [http://svnbook.red-bean.com/nightly/en/svn.reposadmin.html#svn.reposadmin.basics.backends Subversion repository storage] 
can be represented by either a [http://svnbook.red-bean.com/nightly/en/svn.reposadmin.html#svn.reposadmin.basics.backends.bdb Berkley DB database] 
(mostly reffered as ''Berkley DB'' type) or by an [http://svnbook.red-bean.com/nightly/en/svn.reposadmin.html#svn.reposadmin.basics.backends.fsfs ordinary filesystem] 
(mostly reffered as ''FSFS'' type).

== Creating a Subversion repository manually ==
A Subversion distribution package (it can be downloaded from the [http://subversion.tigris.org Subversion home site]) 
includes a tool called '''svnadmin''' which is responsible for creating repositories. When you install Subversion you 
can create a repository performing a command in the command prompt:

 ...>svnadmin create C:\path

This will create an FSFS repository at the path you specify. You may also explicitly provide the type of a repository 
back-end:

 ...>svnadmin create --fs-type bdb C:\path

The layout of a repository root directory looks like this:

 /
 |_conf/
 |_dav/
 |_db/
 |_hooks/
 |_locks/
 |_format
 |_readme.txt
  
Read [http://svnbook.red-bean.com/nightly/en/svn.reposadmin.create.html official instructions] how to create and set up 
a repository on your computer using official Subversion tools.

== Creating a Subversion repository with SVNKit ==
'''SVNKit''' provides an ability to create only FSFS-type repositories. The following is a code snippet which 
demonstrates how you can create a blank repository using '''SVNKit''':

<java>
import org.tmatesoft.svn.core.io.SVNRepositoryFactory;
import org.tmatesoft.svn.core.SVNURL;
import org.tmatesoft.svn.core.SVNException;

...

    try {
        String tgtPath = "C:/repos/root/path";
        SVNURL tgtURL = SVNRepositoryFactory.createLocalRepository(new File(tgtPath), true, false);
    } catch(SVNException e) {
        //handle exception
    }

...
</java>
This will create an FSFS-type repository at path ''"C:/repos/root/path"''.  

<p>
The second parameter of the ''createLocalRepository(...)'' method set to ''true'' enables modifications to 
[http://svnbook.red-bean.com/nightly/en/svn.reposadmin.html#svn.reposadmin.basics.revprops revision properties] of the 
created repository. As revision properties are unversioned, there's a risk to lose their values forever if changes 
to them are allowed. To allow revision properties changing you have to place an executable ''pre-revprop-change'' 
[http://svnbook.red-bean.com/nightly/en/svn.reposadmin.create.html#svn.reposadmin.create.hooks hook script]
file into the ''hooks'' directory (see the repository root directory layout above). When someone is trying to change a 
revision property, a server (say, [http://svnbook.red-bean.com/nightly/en/svn.serverconfig.svnserve.html svnserve]) 
first invokes a ''pre-revprop-change'' hook. If this hook script is not found in the ''hooks'' directory, or the script 
returns a non-zero value, modifications to revision properties are rejected by the server.

<p>
When you create a new repository with the Subversion's '''svnadmin''' tool a new repository's ''hook'' directory 
contains no real hook files, but only hook templates. This means that you won't be able to change revision properties 
until you place a ''pre-revprop-change'' hook manually into the target ''hooks'' directory. With '''SVNKit''' enabling 
changes to revision properties is quite straightforward. When the second parameter of the ''createLocalRepository(...)''
methos is ''true'' '''SVNKit''' places an empty executable ''pre-revprop-change'' hook script into the ''hooks'' 
directory of a new repository. Such a hook does nothing, simply returns 0 letting the requested change operation perform.
However when this parameter is ''false'' no hook scripts are added (but only templates), and revision properties changing 
is disabled.

<p>
The third parameter of the ''createLocalRepository(...)'' method controls whether a repository creation must be forced 
or not. That is, if this parameter is ''true'' and a repository already exists at the path you provide to 
''createLocalRepository(...)'' '''SVNKit''' replaces it with a new repository. However if it's ''false'' an existing 
repository is not removed and a new repository creation fails with an [http://svnkit.com/kb/javadoc/org/tmatesoft/svn/core/SVNException.html SVNException].

<p>
If a repository is successfully created the ''createLocalRepository(...)'' method returns a ''file:///'' url of the 
repository root location.

<p>
Also you may create an FSFS-type repository with [http://svnkit.com/kb/javadoc/org/tmatesoft/svn/core/wc/SVNAdminClient.html SVNAdminClient] - 
the class belonging to high-level API. Actually this admin client class uses [http://svnkit.com/kb/javadoc/org/tmatesoft/svn/core/io/SVNRepositoryFactory.html SVNRepositoryFactory]
to do the same job.

<java>
import org.tmatesoft.svn.core.wc.SVNAdminClient;
import org.tmatesoft.svn.core.SVNURL;
import org.tmatesoft.svn.core.SVNException;

...

    try {
        String tgtPath = "C:/repos/root/path";
        SVNURL tgtURL = SVNRepositoryFactory.doCreateRepository(new File(tgtPath), null, true, false);
    } catch(SVNException e) {
        //handle exception
    }

...
</java>

== Accessing a repository ==
There are two ways of accessing a Subversion repository: 
* over a network
* on a local machine

[[Image:Subversion_Architecture.png]]

Up to now Subversion supports the following repository access schemes:

{|border=1
|bgcolor=#AACCFF|Schema||bgcolor=#AACCFF|Access Method
|-
|file:///||direct repository access (on a 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
|}

=== file:/// access ===
This protocol does not require you to set up a user account for the repository to work with since the repository is 
located on the same computer. Subversion will use only a user name in commit operations: if no user name is provided 
explicitly, a session user name is used.

=== svn://, svn+ssh:// access ===
To use the ''svn://'' protocol an administrator configures access rules and accounts that will be used by an '''svnserve''' 
program to authenticate users. ''svn+ssh://'' protocol: first a client authenticates himself to a host 
server over an ssh, a tunneled connection is established and further he works with a repository just like on a local 
machine. You may try either technique, details are described in [http://svnbook.red-bean.com/nightly/en/svn.serverconfig.svnserve.html this chapter] 
of the Subversion book.

=== http://, https:// access ===
To use the ''http:// '' protocol an dministrator configures an Apache server with a WebDAV protocol extension modules. 
How to share your repository access over ''http:// '' (including acount configuration tips), please, be sure to read 
the [http://svnbook.red-bean.com/nightly/en/svn.serverconfig.httpd.html Apache dedicated chapter] of the Subversion 
book.

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[[What Is Subversion For|<<]] ... [[SVNKit Architecture|>>]]