As part of migrating applications from EC2 instance to kubernetes I was assigned with a task of containerizing a CodeIgniter application. once the application was containerized I noticed that the application logs were writing to a local file inside the container. so I thought this can be easily fixed by changing the logging path in CodeIgniter config file to php://stdout.
But it was not that easy!!
strangely the log path config in CodeIgniter is a combination of file path + file extension, so if I set the file path as php://stdout and left the file extension part blank, the application will throw an error 'Use a full server path with trailing slash'.
After some digging on google. I found out that there is no easy way to set custom static log path in CodeIgniter and I also found an open feature request for this issue which is not yet implemented by CodeIgniter team :(
Luckily I was able to fix the issue by modifying CodeIgniter logging module which is located at system/core/Log.php, I am not sure if this is an optimal solution , just in-case if you are stuck with similar issue give it a try!
Firstly I removed the file path and file extension check conditions from below code block (system/core/Log.php)
public function __construct()
{
$config =& get_config();
$this->_log_path = ($config['log_path'] !== '') ? $config['log_path'] : APPPATH.'logs/';
$this->_file_ext = (isset($config['log_file_extension']) && $config['log_file_extension'] !== '')
? ltrim($config['log_file_extension'], '.') : 'php';
file_exists($this->_log_path) OR mkdir($this->_log_path, 0755, TRUE);
if ( ! is_dir($this->_log_path) OR ! is_really_writable($this->_log_path))
{
$this->_enabled = FALSE;
}
if (is_numeric($config['log_threshold']))
{
$this->_threshold = (int) $config['log_threshold'];
}
elseif (is_array($config['log_threshold']))
{
$this->_threshold = 0;
$this->_threshold_array = array_flip($config['log_threshold']);
}
if ( ! empty($config['log_date_format']))
{
$this->_date_fmt = $config['log_date_format'];
}
if ( ! empty($config['log_file_permissions']) && is_int($config['log_file_permissions']))
{
$this->_file_permissions = $config['log_file_permissions'];
}
}
This is how the code block looks after removing all the checks
public function __construct()
{
$config =& get_config();
$this->_enabled = TRUE;
}
Now you need to replace below line
$filepath = $this->_log_path.'log-'.date('Y-m-d').'.'.$this->_file_ext;
with this line (use a static file path instead of a dynamic one)
$filepath = $this->_log_path;
Now find and remove the below block code from the file (used for changing permission of log file, not needed in our case)
if (isset($newfile) && $newfile === TRUE)
{
chmod($filepath, $this->_file_permissions);
}
And finally make changes to the CodeIgniter main config file (application/config/config.php) as below
/*
|--------------------------------------------------------------------------
| Error Logging Threshold
|--------------------------------------------------------------------------
|
| You can enable error logging by setting a threshold over zero. The
| threshold determines what gets logged. Threshold options are:
|
| 0 = Disables logging, Error logging TURNED OFF
| 1 = Error Messages (including PHP errors)
| 2 = Debug Messages
| 3 = Informational Messages
| 4 = All Messages
|
| You can also pass an array with threshold levels to show individual error types
|
| array(2) = Debug Messages, without Error Messages
|
| For a live site you'll usually only enable Errors (1) to be logged otherwise
| your log files will fill up very fast.
|
*/
$config['log_threshold'] = 4;
/*
|--------------------------------------------------------------------------
| Error Logging Directory Path
|--------------------------------------------------------------------------
|
| Leave this BLANK unless you would like to set something other than the default
| application/logs/ directory. Use a full server path with trailing slash.
|
*/
$config['log_path'] = 'php://stdout';
/*
|--------------------------------------------------------------------------
| Log File Extension
|--------------------------------------------------------------------------
|
| The default filename extension for log files. The default 'php' allows for
| protecting the log files via basic scripting, when they are to be stored
| under a publicly accessible directory.
|
| Note: Leaving it blank will default to 'php'.
|
*/
$config['log_file_extension'] = '';
/*
|--------------------------------------------------------------------------
| Log File Permissions
|--------------------------------------------------------------------------
|
| The file system permissions to be applied on newly created log files.
|
| IMPORTANT: This MUST be an integer (no quotes) and you MUST use octal
| integer notation (i.e. 0700, 0644, etc.)
*/
$config['log_file_permissions'] = '';
/*
|--------------------------------------------------------------------------
| Date Format for Logs
|--------------------------------------------------------------------------
|
| Each item that is logged has an associated date. You can use PHP date
| codes to set your own date formatting
|
*/
$config['log_date_format'] = '';
/*
|--------------------------------------------------------------------------
| Error Views Directory Path
|--------------------------------------------------------------------------
|
| Leave this BLANK unless you would like to set something other than the default
| application/views/errors/ directory. Use a full server path with trailing slash.
|
*/
$config['error_views_path'] = '';
Once these changes are deployed you will be able to the see the application logs in container’s STDOUT and STDERR logs (docker/kubernetes logs).