How to configure CodeIgniter database file based on user input using PHP?

Question

Suppose I have a database configuration form like the following image:

In CodeIgniter, the user needs to edit the files at ...\\application\\config\\database.php and change the hostname, username, password and other required info.

Now I want to do the task automatically when a user fills out the above form and clicks the "Save" button. I guess I need to perform some file write operation using PHP, but I don't know how to find and replace specific portions of a file.

How can I change hostname, username, password, and database name based on the form input in the CodeIgniter database configuration file?

Answer 1

$db_info = $this->input->post(['hostname', 'username', 'password', 'database']);

You'll have to validate the information provided by the user before actually trying to save anything.

for example; You might try to run mysqli_connect on the provided settings to manually connect like this:

if ( @mysqli_connect($db_info['hostname'], $db_info['username'], $db_info['password'], $db_info['database']) ) {

then you'll have to write these data into the file, which is pretty simple in CodeIgniter.

You'll have to take a copy of database.php & put it somewhere in your installation folder replacing <?php with something like this <?php echo '<?php' . "\\n"; ?> <?php echo '<?php' . "\\n"; ?>

Then you go ahead and replace $db['default'] = array entries adding your custome variables like this

$db['default'] = array(
    'dsn'   => '',
    'hostname' => '<?php echo $hostname; ?>',
    'username' => '<?php echo $username; ?>',
    'password' => '<?php echo $password; ?>',
    'database' => '<?php echo $database; ?>',
    'dbdriver' => 'mysqli',
    'dbprefix' => '',
    'pconnect' => FALSE,
    'db_debug' => TRUE,
    'cache_on' => FALSE,
    'cachedir' => '',
    'char_set' => 'utf8',
    'dbcollat' => 'utf8_general_ci',
    'swap_pre' => '',
    'autoinit' => TRUE,
    'encrypt' => FALSE,
    'compress' => FALSE,
    'stricton' => FALSE,
    'failover' => array(),
    'save_queries' => TRUE
);

After that it's as easy as loading the view in your controller & caching it to a variable for example

$DBConfig = $this->load->view('install/config/database', $db_info, TRUE);

Then writing the output to the desired path as follows:

$this->load->helper('file');
write_file(APPPATH.'config/database.php', $DBConfig);