[development] Any reason why having a javascript timer fire every 2.5 second for an ajax request to my own callback(listed below) that all it does is return the contents of 2 _session variables would take up so much resources?

[John Mitchell]

Regarding:
*require_once './includes/bootstrap.inc';
drupal_bootstrap(DRUPAL_BOOTSTRAP_CONFIGURATION);
// Choose the minimum bootstrap level necessary for your module.*

Thanks for the below information.  If all I want to do is just send an ajax
call to a drupal url which points to a callback that only has a return
statement in it (originally I returned the contents of 2 session variables
but I will eliminate that if it causes additional overhead).  What would the
minumum parameter for drupal_bootstrap needed for the scenario listed above?

According to the documentation it appears to be
DRUPAL_BOOTSTRAP_CONFIGURATION.
Am I correct that I should use DRUPAL_BOOTSTRAP_CONFIGURATION as the
parameter?

Thanks,

John
Parameters

$phase A constant. Allowed values are: DRUPAL_BOOTSTRAP_CONFIGURATION:
initialize configuration. DRUPAL_BOOTSTRAP_EARLY_PAGE_CACHE: try to call a
non-database cache fetch routine. DRUPAL_BOOTSTRAP_DATABASE: initialize
database layer. DRUPAL_BOOTSTRAP_ACCESS: identify and reject banned hosts.
DRUPAL_BOOTSTRAP_SESSION: initialize session handling.
DRUPAL_BOOTSTRAP_LATE_PAGE_CACHE: load
bootstrap.inc<http://api.drupal.org/api/drupal/includes--bootstrap.inc/6>and
module.inc <http://api.drupal.org/api/drupal/includes--module.inc/6>, start
the variable system and try to serve a page from the cache.
DRUPAL_BOOTSTRAP_LANGUAGE: identify the language used on the page.
DRUPAL_BOOTSTRAP_PATH: set $_GET['q'] to Drupal path of request.
DRUPAL_BOOTSTRAP_FULL: Drupal is fully loaded, validate and fix input data.


On Sun, Feb 6, 2011 at 12:21 PM, Greg Knaddison <
greg at growingventuresolutions.com> wrote:

> Drupal's bootstrap takes something like 50% of the total page
> processing time on a typical page. You are still paying for that
> overhead even though you don't need it.
>
> See
> http://api.drupal.org/api/drupal/includes--bootstrap.inc/function/drupal_bootstrap/6
> and look at something like the chatroom module's lightweight bootstrap
> code:
>
>
> http://drupalcode.org/viewvc/drupal/contributions/modules/chatroom/chatroomread.php?revision=1.29.4.19&view=markup
>
> In particular:
>
> require_once './includes/bootstrap.inc';
> drupal_bootstrap(DRUPAL_BOOTSTRAP_CONFIGURATION);
> // Choose the minimum bootstrap level necessary for your module.
>
> // Put your code here.
> // See performance skyrocket.
> // Rejoice.
>
> Regards,
> Greg
>
> On Sun, Feb 6, 2011 at 10:15 AM, John Mitchell <mitchelljj98 at gmail.com>
> wrote:
> > Any reason why having a javascript timer fire every 2.5 second for an
> ajax
> > request to my own callback(listed below) that all it does is return the
> > contents of 2 _session variables would take up so much resources?
> >
> > John
> >
> > function refreshcarttimer() {
> >     print($_SESSION['num_items'] . ',' .  $_SESSION['uc_price']);
> >     return;
> > }
> >
> > /**
> >  * Implementation of hook_menu().
> >  */
> >
> > function product_type_menu() {
> >   $items = array();
> >
> >   $items['cart/refreshcarttimer'] = array(
> >     'title' => 'Refresh Shopping Cart',
> >     'description' => 'Refresh Shopping Cart',
> >     'page callback' => 'refreshcarttimer',
> >     'access callback' => TRUE,
> >     'type' => MENU_CALLBACK,
> >   );
> >   return $items;
> > }
> >
> > On Sun, Feb 6, 2011 at 2:10 AM, John Mitchell <mitchelljj98 at gmail.com>
> > wrote:
> >>
> >> I have a javascript timer set to fire every 2.5 seconds so that I can
> set
> >> the current values for the items and total for the shopping cart
> summary.  I
> >> would like to be able to get these values from client side cookies or
> >> javascript global variables so that I don't have to make an ajax call to
> the
> >> server but I have found that the DOM elements are not accessible within
> the
> >> javascript function unless I run an ajax request to a page (listed
> below)
> >> and after it returns then the DOM elements are accessible (i.e.
> >> $(".num-items").html(numItems);) and now I can update them.  Having
> these
> >> ajax requests run every 2.5 seconds for every client will not scale.
> >>
> >> How can I make Drupal DOM elements accessible within a javascript
> function
> >> without having to do an ajax request to a page?
> >>
> >> Thanks,
> >>
> >> John
> >>
> >>     setInterval('updateShoppingCartInfo()', 2500);
> >>
> >>     function updateShoppingCartInfo(){
> >>         var xmlHttpReq = new XMLHttpRequest();
> >>         var url = 'https://' + document.domain +
> '/cart/refreshcarttimer';
> >>         xmlHttpReq.open('post', url, true);
> >>         xmlHttpReq.onreadystatechange = function() {
> >>                if (xmlHttpReq.readyState != 4)  {
> >>                    return;
> >>                }
> >>             else {
> >>                 var responseText = xmlHttpReq.responseText;
> >>                                 var numItems =
> >> responseText.substr(0,responseText.indexOf(","));
> >>                                 var ucPrice =
> >> responseText.substr(responseText.indexOf(",")+1);
> >>                                 $(".num-items").html(numItems);
> >>                                 $(".uc-price").html(ucPrice);
> >>             }
> >>         }
> >>         xmlHttpReq.send(null);
> >>     }
> >>
> >>
> >> --
> >> John J. Mitchell
> >
> >
> >
> > --
> > John J. Mitchell
> >
>
>
>
> --
> Greg Knaddison | 720-310-5623 | http://growingventuresolutions.com
> http://masteringdrupal.com - Videos and Tutorials
>



-- 
John J. Mitchell
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.drupal.org/pipermail/development/attachments/20110206/5d8506e7/attachment-0001.html