How to keep a stable KwaMoja/webERP installation updated

There has been a lot of discussion recently on the webERP forums about how to keep a stable version of your implementation, so I thought it might be a good moment to write an article on how to do this.

Firstly Web ERP Africa Ltd keeps a stable branch of the webERP code. This takes the last release (4.10.1 at the moment I write this) and then just adds in any bug fixes that have been applied to the main line. Obviously this does not include any bug fix to any new functionality, as that functionality does not exist in the stable branch. We also apply our regression tests to these fixes, to ensure that they are not re-introducing any previous bugs. This branch should then get progressively more stable, but anybody  who wants the latest features can use the main trunk. I have made this stable branch publicly available from my github repository and can be found here. You can download a zip file containing this code from here. This zip file is automatically updated when a new bug fix is applied.

Exactly the same is true for KwaMoja, it's stable branch can be found by using the master branch here.

So if you are using a KwaMoja/webERP that has no customisations in it then all you have to do, is to keep an eye on this repository, and download new versions as and when it is updated.

However there are potential problems when you have customised scripts in your installation. I will assume that if the user has the knowledge to change the files then they will have a small knowledge of IT, and you will need the application Git installed.
 
What we wish is to avoid the code being over written when updating from the stable branch. I have created a small git repository here to represent the stable branch, and have uploaded the following script to it, calling it HelloWorld.php:

<?php
include('includes/session.inc');
$Title = _('Hello World');
include('includes/header.inc');
echo '<p class="page_title_text noPrint" ><img src="'.$RootPath.'/css/'.$Theme.'/images/user.png" width="24px" title="' . _('Hello World') . '" alt="" />' . _('Hello World') . '</p>';
if (isset($_POST['Submit'])) {
    /* Get clients IP address */
    $IPAddress = $_SERVER['REMOTE_ADDR'];
    /* Has user been here before? */
    $SQL = "SELECT count(name) as names
                FROM helloworld
                WHERE name='" . $_POST['Name'] . "'
                    AND ipaddress='" . $IPAddress . "'";
    $Result = DB_query($SQL, $db);
    $MyRow = DB_fetch_array($Result);
    if ($MyRow['names'] > 0) {
        prnMsg( _('Welcome back') . ' ' . $_POST['Name'], 'info');
    } else {
        $SQL = "INSERT INTO helloworld (ipaddress,
                                        name)
                                    VALUES (
                                        '" . $IPAddress . "',
                                        '" . $_POST['Name'] . "'
                                    )";
        $Result = DB_query($SQL, $db);
        prnMsg( _('Hi') . ' ' . $_POST['Name'], 'info');
    }
} else {
    echo '<div class="page_help_text noPrint">' . _('Enter your name in the box below.') . '</div>';
    echo '<form enctype="multipart/form-data" action="' . htmlspecialchars($_SERVER['PHP_SELF'],ENT_QUOTES,'UTF-8') . '" method="post" class="noPrint">';
    echo '<input type="hidden" name="FormID" value="' . $_SESSION['FormID'] . '" />';
    echo '<div class="centre">
            <input type="text" name="Name" />
        </div>
        <div class="centre">
            <input type="submit" name="Submit" value="Submit" />
        </div>';
    echo '</form>';
}
include('includes/footer.inc');
?>

Now you can pull this code to your own machine by issuing the command:

git clone git@github.com:timschofield/Example1.git

Now we make a local change to our code. We will change the word 'Hi' to 'Hello'. Now if we wish to update our code to the latest from the repository we would issue the command:

git pull git@github.com:timschofield/Example1.git

and this will update any changes - if there were any new bug fixes applied for instance. However you will notice that Git is smart enough not to try and overwrite your code that you changed locally.

So by using Git we can update our code to the latest stable branch, whilst keeping our local changes in place.