2.1. Requirements

SVNChecker requires at least python 2.4 and Subversion 1.2. It runs on both, Windows and *nix. Some checks may depend on external tools. For the requirements of the individual checks take a look at the "Available Modules" section.

2.2. Download

SVNChecker is available from the project side at tigris .

2.3. Hooks

After extracting the SVNChecker package to an arbitrary directory, you have to create two files in your Subversion hooks directory. On *nix systems those files are named pre-commit and post-commit and must be set executable. They contain the following content, where %pathtosvnchecker% is replaced by the directory to which you unpacked the SVNChecker and %hook% is either PreCommit or PostCommit (case-sensitive):

#!/bin/sh
/usr/bin/env python %pathtosvnchecker%/Main.py %hook% $1 $2 || exit 1
				

%pathtopython% %pathtosvnchecker%/Main.py %hook% $1 $2 || exit 1
				

3.1. Configuration Files

The SVNChecker can use any combination of the following two configuration files. The first one is a global configuration file which affects all repositories installed on the same system and must be located in the SVNChecker directory, just aside of "Main.py", named "svncheckerconfig.ini". The second one is a repository local configuration file which must be located in the "hooks" directory of a repository and names "svncheckerconfig.ini" as well. If only one of those configuration files exist, this only one will be used. If both exist, the options from the global file will override the options from the local one. The file format is a simple ini-like format with categories, which are used for profiles, and key=value pairs.

3.2. Basic configuration

The basic configuration of the SVNChecker is very simple. It starts with a category, named "Default". After that you need to specify which checks to activate for the pre-commit and post-commit hooks. For each check you then activate the desired handlers for the success and failure cases. An example is shown below:

[Default]
Main.PreCommitChecks=Pylint, XMLValidator
Main.PostCommitChecks=Log

Pylint.SuccessHandlers=Console, Mail
Pylint.FailureHandlers=Console, Mail

XMLValidator.SuccessHandlers=Console, Mail
XMLValidator.FailureHandlers=Console, Mail

Log.SuccessHandlers=Console, Mail
Log.FailureHandlers=Console, Mail
				

3.3. Resolving of Variables

You might have seen in the previous example that the flexibility is very high, you can configure a success and failure handlers for each check. But this can make the configuration file very big and unclear, typing the same code every time although you want to use the same handlers for all checks. Furthermore one configuration option may be required by more then one check, e.g. the path to the java binary. To support those cases the SVNChecker does not only look for the real name of the specified configuration option. If it can't find the complete name it will substitute the first part of the check, the one before the "." with "Main". So the previous example could have also been written as:

[Default]
Main.PreCommitChecks=Pylint, XMLValidator
Main.PostCommitChecks=Log

Main.SuccessHandlers=Console, Mail
Main.FailureHandlers=Console, Mail
				

3.4. Profiles

If your repository grows or you manage different trunks and branches, you might want to configure specific settings for different parts of the repository. In order to do that the SVNChecker support profiles. Profiles allow you to configure different settings of the SVNChecker for different files or paths in the repository. Profiles are defined by categories in the configuration file and must have a "Main.Regex" configuration option which specifies a regular expression which matches all files this profile is valid for. All files that didn't match a profile will be checked against the "Default" profile. Here an example profile that disables all PreCommitChecks for branches:

[Default]
Main.PreCommitChecks=Pylint, XMLValidator
Main.PostCommitChecks=Log

Main.SuccessHandlers=Console, Mail
Main.FailureHandlers=Console, Mail

[Branches]
Main.Regex=^branches/.*$
Main.PreCommitChecks=
				

3.5. Variable Substitution

Sometimes it might be useful to know the path of the hooks directory of the repository in your configuration file, e.g. when writing log files. For this purpose you can use the string "%HOOKS%", which will be replaced by the real directory during runtime.

4.1. Checks

4.2. Handlers

5.1. The Transaction class

The Transaction class gives you all information you need to know about the commit and the repository. It has the following methods:

5.2. The Config class

The Configuration class provides you with all required methods to access configuration variables:

5.3. Implementing a Check

To implement a new Check you only need to write a python module containing a method named "run", with two parameters, "transaction" and "config". The return value must be a tuple containing the return message and the exit code. You have to put the check into the "checks" package of the SVNChecker. Here an example of a simple check, testing if a xml file is parseable:

from xml.dom import minidom
from xml.parsers import expat

def run(transaction, config):

    check = config.getArray("XMLValidator.CheckFiles", [".*\.xml"])
    ignore = config.getArray("XMLValidator.IgnoreFiles", [])
    files = transaction.getFiles(check, ignore)

    msg= ""
    for filename, attribute in files.iteritems():
        if attribute in ["A", "U"]:
            try:
                minidom.parse(transaction.getFile(filename))
            except expat.ExpatError, e:
                msg += "XML Validation error in file %r: %s" % (filename, e)

    if msg:
        return (msg, 1)
    else:
        return ("", 0)
				

5.4. Implementing a Handler

To implement a new Handler you only need to write a python module containing a method named "run", with five parameters, "transaction", "config", "check", "msg" and "exitCode". "check" is the name of the just executed check. Here an example of a simple handler, printing the output to the console:

import sys

separator = "\n" + "=" * 80 + "\n"

def run(transaction, config, check, msg, exitCode):

    if (exitCode == 1):
        out = sys.stderr
    else:
        out = sys.stdout

    out.write(separator)
    out.write(msg)
    out.write(separator)
				

6.1. Version 0.2.1

• Fixed bug in the pylint check that made the check pass although it failed.

• Made the "Pylint.ConfigFile" configuration option optional, a default pylintrc will be used if you don't specify it.

• Fixed a bug in the transaction module that returned an empty file when calling getFile() more than once.

• Fixed a bug in the transaction module to avoid a deadlock when receiving big files.

• Make the SVNChecker compatible with python 2.4.

6.2. Version 0.2

This is the first big revision of the SVNChecker. The interfaces to implement a Check or Handler were changed. Furthermore the Transaction and Config classes have been improved. If you develop your own modules take a look at the updated "Developers Guide". A lot of checks have been enhanced, e.g. Checkstyle and Pylint are faster now, and new Checks were added, including Checkout and CaseInsensitiveFilenameClash. For a complete reference of the available Checks and Handlers and their configuration options take a look at the "Available Modules" section. The configuration now supports a system-wide file which can define configuration options which are fixed for all installed repositories. If you want to use the hooks directory in the configuration file you can now use %HOOKS%, which will automatically be replaced by the real directory. With the help of a new test-environment all modules have undergone a better testing for improved stability. A complete list of fixed issues is available via the issue tracker at the tigris project page.