Rendering path for HTML web page

Here is the steps the browser takes to render a web page after receiving the content from the server:

  1. Constructing the DOM Tree
  2. Constructing the CSSOM Tree
  3. Running JavaScript
  4. Creating the Render Tree
  5. Generating the Layout
  6. Painting

You can use Google chrome DevTool “Performance” to view rendering in progress with details and charts.

For more details, check this page: 

https://bitsofco.de/understanding-the-critical-rendering-path/

How to view latest SQL statement excuted in Laravel

To view the latest sql query executed in Laravel you can

DB::enableQueryLog();

print_r(DB::getQueryLog());

Note that you have to enable the query log before executing the query and view/print it after execution ..

A good practice is to enable it only in Local environment

if (App::environment('local')) {
    // The environment is local
    DB::enableQueryLog();
}

 

How to sanitize raw data in Laravel

When doing a raw data query from user input like this:

$someVariable = Input::get("some_variable");

$results = DB::select( DB::raw("SELECT * FROM some_table WHERE some_col = '$someVariable'") );

we are at risk of SQL injection , to avoid that we can bin parameters to our query like this:

$someVariable = Input::get("some_variable");

$results = DB::select( DB::raw("SELECT * FROM some_table WHERE some_col = :somevariable"), array(
   'somevariable' => $someVariable,
 ));

 

Another point is that if we want to do a raw that doesn’t return a value, we can do it like this

DB::statement( 'ALTER TABLE HS_Request AUTO_INCREMENT=1111' );

and that way can take parameters as well

DB::statement( 'ALTER TABLE HS_Request AUTO_INCREMENT=:incrementStart', array('incrementStart' => 1111) );

 

How to measure timing in Laravel using debugbar

If you want to measure the timing of some code in Laravel , you can use debugbar measure function

Debugbar::startMeasure('start');

Debugbar::stopMeasure('stop');

but if, for any reason, you can’t use debugbar, you can go back to pure php and use this code

 $start = microtime(true);
 
 $time_elapsed_secs = microtime(true) - $start;