log_this: A helper logging function for WordPress/PHP

Here’s a nice little PHP helper function I’ve been using for the past few years for debugging my code:

if ( !function_exists( 'log_this' ) ){
    function log_this( $title, $data = false ){

        if ( func_num_args( ) === 0 ){
            return false;
        }
        elseif ( func_num_args( ) === 1 ){
            $data = $title;
            $title = "LOG";
        }

        $border_char = "/";
        $border_length_bottom = 100;
        $border_length_top = $border_length_bottom - strlen( $title ) - 2;

        $border_length_top_left = floor( $border_length_top/2 );
        $border_length_top_right = ceil( $border_length_top/2 );

        $border_top_left = str_pad( "", $border_length_top_left, $border_char );
        $border_top_right = str_pad( "", $border_length_top_right, $border_char );

        error_log( "\n\n" );
        error_log( "$border_top_left $title $border_top_right" );

        if ( is_array( $data ) || is_object( $data ) ){
            error_log( print_r( $data, true ) );
        }
        else{
            error_log( "" );
            error_log( $data );
            error_log( "" );
        }
        error_log( str_pad( "", $border_length_bottom, $border_char ) . "\n" );
    }
}

As you can see, this is mostly a wrapper around the built-in error_log PHP function with the advantage of letting you log arrays without needing to use print_r. And it makes the variables you’re logging easier to see in a crowded log file.

Here’s an example use.

$hello = 'world';
log_this( $hello );

/////////////////////////////////////////////// LOG ////////////////////////////////////////////////

world

////////////////////////////////////////////////////////////////////////////////////////////////////

And now with an array.

$user = array(
    'name' => 'Stefan',
    'location' => 'Brooklyn, New York',
    'number_of_pets' => 1
);

log_this( $user );

/////////////////////////////////////////////// LOG ////////////////////////////////////////////////
Array
(
    [name] => Stefan
    [location] => Brooklyn, New York
    [number_of_pets] => 1
)

////////////////////////////////////////////////////////////////////////////////////////////////////

And here’s a more complex example that also shows how you can modify the text before your variable, making it easier to find it by searching that text.

$hello = 'world';
$my_number = 12345;
$user = array(
    'name' => 'Stefan',
    'location' => 'Brooklyn, New York',
    'number_of_pets' => 1
);

log_this( 'debugging:user data', array(
    '$hello' => $hello,
    '$my_number' => $my_number,
    '$user' => $user,
) );

/////////////////////////////////////// debugging:user data ////////////////////////////////////////
Array
(
    [$hello] => world
    [$my_number] => 12345
    [$user] => Array
        (
            [name] => Stefan
            [location] => Brooklyn, New York
            [number_of_pets] => 1
        )

)

////////////////////////////////////////////////////////////////////////////////////////////////////