Browser cache is very useful when users download the same CSS and JS files multiple times. Some browsers, however, use the old CSS and JS files from the cache, even though they have been updated. This may lead to unpleasant situations, when the pages are displayed to the user with the wrong styles or pages will work incorrectly.
Fortunately, these unpleasant situations is easy to avoid and let the browsers cache files as long as they are changed.
It makes sense to optimize the site’s cascading style sheets (CSS), as it pages load faster, and it reduce the amount of data transferred, and just combining css files could significantly reduce requests to server. So users benefit from faster page loads and webmaster of the sites benefits from the cheaper price of the transferred data.
I have used CSSTidy on many projects. And CSSTidy is very good tool for packing CSS and it can even fix CSS errors. Sometimes, however, feel that csstidy is even a bit too wide and “heavy” tool for the CSS files packing. Thats why I decide to write my own simple PHP class for the CSS files packing.
Today I started thinking that how cool is do some Google searches straight from command line. First I try to find some ready tricks from the Internet, but I couldn’t find quickly anything good. So I decide do a simple Bash function that can take Google search as parameter and open Firefox Browser (tab) with Google search. Sounds easy… :)
First we need Google search URL without search parameter and it looks like this:
As Part 1 (Howto create PostgreSQL table partitioning) shows, making of PostgreSQL partitioning needs a lot of SQL commands. So this Part 2 explains how SQL commands for PostgreSQL partitioning can be made with a simple PHP script. This example script make SQL for child tables, indexes, trigger function and parent table trigger. This example script can make PostgreSQL table partitioning with using Date ranges. Script can be configured with following configuration section:
This is very easy way loop through dates (from date to date) with PHP strtotime() function. This example only echo dates, but of course this model can be used more complicated situations.
<?php // Set timezone date_default_timezone_set('UTC'); // Start date $date = '2009-12-06'; // End date $end_date = '2020-12-31'; while (strtotime($date) <= strtotime($end_date)) { echo "$date\n"; $date = date ("Y-m-d", strtotime("+1 day", strtotime($date))); } Note: All different PHP strtotime() function syntaxes can be used.
I think every PHP coders have come accross Arrays and stdClass Objects (belongs to PHP Predefined Classes). Sometimes it’s very useful convert Objects to Arrays and Arrays to Objects. This is easy if arrays and objects are one-dimensional, but might be little tricky if using multidimensional arrays and objects.
This post defines two ultra simple recursive function to convert multidimensional Objects to Arrays and multidimensional Arrays to Objects.
Function to Convert stdClass Objects to Multidimensional Arrays <?php function objectToArray($d) { if (is_object($d)) { // Gets the properties of the given object // with get_object_vars function $d = get_object_vars($d); } if (is_array($d)) { /* * Return array converted to object * Using __FUNCTION__ (Magic constant) * for recursive call */ return array_map(__FUNCTION__, $d); } else { // Return array return $d; } } Function to Convert Multidimensional Arrays to stdClass Objects <?php function arrayToObject($d) { if (is_array($d)) { /* * Return array converted to object * Using __FUNCTION__ (Magic constant) * for recursive call */ return (object) array_map(__FUNCTION__, $d); } else { // Return object return $d; } } Function usage // Create new stdClass Object $init = new stdClass; // Add some test data $init->foo = "Test data"; $init->bar = new stdClass; $init->bar->baaz = "Testing"; $init->bar->fooz = new stdClass; $init->bar->fooz->baz = "Testing again"; $init->foox = "Just test"; // Convert array to object and then object back to array $array = objectToArray($init); $object = arrayToObject($array); // Print objects and array print_r($init); echo "\n"; print_r($array); echo "\n"; print_r($object); Test output:
In many cases, it is really useful to know the exact time for how long a PHP script is running or how long will take PHP web page load. On the other hand it is also useful to know that how long a particular script operation or part of page load will take.
Following PHP Timing class is very simple to use, only create class and start timing and stop timing. Elapsed time function can be used also (elapsed time is calculated from script start time). Statistics can be displayed in print-functions and the same information without any formatting can also get with get-functions.
PHP Command Line Interface (CLI) has not built-in coloring for script output, like example Perl language has (perldoc.perl.org/Term/ANSIColor.html). So I decided to make own class for adding colors on PHP CLI output. This class works only Bash shells. This class is easy to use. Just create new instance of class and call getColoredString function with string and foreground color and/or background color.
PHP Class for Coloring PHP Command Line (CLI) Scripts Output <?php class Colors { private $foreground_colors = array(); private $background_colors = array(); public function __construct() { // Set up shell colors $this->foreground_colors['black'] = '0;30'; $this->foreground_colors['dark_gray'] = '1;30'; $this->foreground_colors['blue'] = '0;34'; $this->foreground_colors['light_blue'] = '1;34'; $this->foreground_colors['green'] = '0;32'; $this->foreground_colors['light_green'] = '1;32'; $this->foreground_colors['cyan'] = '0;36'; $this->foreground_colors['light_cyan'] = '1;36'; $this->foreground_colors['red'] = '0;31'; $this->foreground_colors['light_red'] = '1;31'; $this->foreground_colors['purple'] = '0;35'; $this->foreground_colors['light_purple'] = '1;35'; $this->foreground_colors['brown'] = '0;33'; $this->foreground_colors['yellow'] = '1;33'; $this->foreground_colors['light_gray'] = '0;37'; $this->foreground_colors['white'] = '1;37'; $this->background_colors['black'] = '40'; $this->background_colors['red'] = '41'; $this->background_colors['green'] = '42'; $this->background_colors['yellow'] = '43'; $this->background_colors['blue'] = '44'; $this->background_colors['magenta'] = '45'; $this->background_colors['cyan'] = '46'; $this->background_colors['light_gray'] = '47'; } // Returns colored string public function getColoredString($string, $foreground_color = null, $background_color = null) { $colored_string = ""; // Check if given foreground color found if (isset($this->foreground_colors[$foreground_color])) { $colored_string .= "\033[" . $this->foreground_colors[$foreground_color] . "m"; } // Check if given background color found if (isset($this->background_colors[$background_color])) { $colored_string .= "\033[" . $this->background_colors[$background_color] . "m"; } // Add string and end coloring $colored_string .= $string . "\033[0m"; return $colored_string; } // Returns all foreground color names public function getForegroundColors() { return array_keys($this->foreground_colors); } // Returns all background color names public function getBackgroundColors() { return array_keys($this->background_colors); } } Colors class basic usage examples <?php // Create new Colors class $colors = new Colors(); // Test some basic printing with Colors class echo $colors->getColoredString("Testing Colors class, this is purple string on yellow background.", "purple", "yellow") . "\n"; echo $colors->getColoredString("Testing Colors class, this is blue string on light gray background.", "blue", "light_gray") . "\n"; echo $colors->getColoredString("Testing Colors class, this is red string on black background.", "red", "black") . "\n"; echo $colors->getColoredString("Testing Colors class, this is cyan string on green background.", "cyan", "green") . "\n"; echo $colors->getColoredString("Testing Colors class, this is cyan string on default background.", "cyan") . "\n"; echo $colors->getColoredString("Testing Colors class, this is default string on cyan background.", null, "cyan") . "\n"; Output:
I was using simple function to calculate difference between two dates and timestamps until I noticed, it’s not working correctly in long intervals. It’s very easy to calculate difference between two timestamps in seconds, but it’s much more complicated print difference in human readable format. The Internet can be found in a wide range of ways to do this thing, but as a rule they use a fixed amount of seconds for the year and the month. So if we calculate year with using 365 or 365.25 days and month using 30 or 31 then the difference is not accurate, because of leap years, DST (Daylight Saving Time) and so on.
This is a very typical case, the need to create a temp file on the command line quickly. Opening editor, writing content, save file and quit editor is not the fastest possible way. A faster way is to use the cat command with the name of the file and write contents of the file and give the end-of-file character (Ctrl-D).
This is guide, howto create (or append to) text file without text editor on Linux shell / command line.
PHP has large number of predefined constants. This HOWTO will present the seven most important, most practical and most useful PHP Magic Constants.
__FILE__ – The full path and filename of the file. __DIR__ – The directory of the file. __FUNCTION__ – The function name. __CLASS__ – The class name. __METHOD__ – The class method name. __LINE__ – The current line number of the file. __NAMESPACE__ – The name of the current namespace This is example PHP script with comments, which demonstrate howto use all previously mentioned PHP Magic Constants.
PHP MongoDB (Mongo Database) Driver Installation on Linux, UNIX, BSD and Mac OS X MongoDB PHP driver is very simple install on Linux, UNIX, BSD and Mac OS X. You need just PEAR (PHP Extension and Application Repository) with PECL repository. Normally PHP development (dev) package and PHP Pear package installation from package management system is enough to get PEAR working. Also go-pear.php script can be used.
Check that the PEAR and PECL are working with the following commands:
PHP’s ucfirst function is very usefull when you want to change words first letters to uppercase and other letters to lowercase. Currently on PHP does not have a multibyte (UTF-8) version of ucfirst function. So I decided write my own multibyte mb_ucfirst function.
Perhaps the multibyte version of ucfirst function is added later on PHP, so that’s why is better add this function only if it does not already exist.
