ESI and cart

Hi,

If you’re using WooCommerce, you should see the “Privately Cache Cart” setting under the “WooCommerce” tab on LSCache settings. Switch this setting to “ON” and you’ll see your shopping cart be served from the private cache.

Hello @tenkstars

Thanks for the answer but perhaps I haven’t been enough clear.
Yes I am using woocommerce and the option Privately Cache Cart is already on.

But, as explained above, when all is working fine when nothing is in the cart (x-lsadc-cache: hit) but if I add something to the cart, the pages that normally are served from cached, aren’t anymore (x-lsadc-cache: miss).

If I visit my site with something in the cart, the first time it’s miss and the second time it’s hit. So here i can deduce that the private cache is working.

But what I don’t get is that I thought that with ESI activated, the pages should be served from the public cache even if something is in the cart.

Thanks again for the help.

BR

P.S when you say “you’ll see your shopping cart be served from the private cache” how can i see it is served from public or private cache

Hi,

this feature may requires theme to be compatible with it , as you can imagine , different theme can have different way to handle the cart

you can enable debug log , and looking for something like this in HTML source code

<!-- lscwp STOREFRONT_CART_HEADER -->		<ul id="site-header-cart" class="site-header-cart menu">
			<li class="">
							<a href="https://xxx/cart/" title="View your shopping cart">
								<span class="woocommerce-Price-amount amount">41,00<span class="woocommerce-Price-currencySymbol">&euro;</span></span> <span class="count">2 items</span>
			</a>
					</li>
			<li>
				<div class="widget woocommerce widget_shopping_cart"><div class="widget_shopping_cart_content"></div></div>			</li>
		</ul>
			<!-- Block generated by LiteSpeed Cache 3.6 on 2021-04-27 23:21:29 --><!-- lscwp STOREFRONT_CART_HEADER esi end --></div></div>
	</header>

`

I tested with storefront theme , if I open some pages, like category page , then add some product into cart , then I refresh on the category page again , I still get cache hit , with cart content updated

Best regards,

• This reply was modified 3 years, 7 months ago by qtwrk.

Hello @qtwrk

Thanks for the reply !

Unfortunately, the only reference to litespeed I can see on the source code after enabling the debug log, it is at the end of the page :

<!-- Page generated by LiteSpeed Cache 3.6.4 on 2021-04-28 01:34:12 -->
<!-- X-LiteSpeed-Cache-Control: public,max-age=604800 -->
<!-- X-LiteSpeed-Tag: 5b2_HTTP.200,5b2_WC_T.52,5b2_tax,5b2_URL.2fb983b276904005244fb9aa62d83e29,5b2_T.52,5b2_ -->

I let the debug log enable if you’d like to check on my test site what could be wrong :
https://f420-ad300e5de1b3.wptiger.fr/

And so, if my theme is not compatible, how can I make it compatible ?

Thanks again for the help !

Best regards

Hi,

this thing is little tricker

you need to have both public cache with and without cart vary generated first

e.g. you will first need to generate a public cache with vary “cart is not empty” and then this public cache will be used for all “cart not empty” cases

then you will have 2 public caches for same pages , one gives to users with empty cart , one gives to users with item in cart

Best regards,

Hello @qtwrk

I do not follow you on this :/

How can I do what you say : generate 2 differents public cache ?

And otherwise isn’t it a way to add something on my theme for the plugin to identify where is the cart ? (btw the cart is ajax)

Thanks again,

Best regards

Hi,

when user has an empty cart , and this user visits page -> it generates public cache with vary “empty cart”

when user has something in cart , and this user visits page -> it generates public cache with vary “not empty cart”

despite they are both public cache , but they may have different content and generation time due to vary

you follow me on this part ?

so when user A with item in cart , visits the pages , first time it will give miss and this action will generate public cache with cart vary

then the second user, user B , with some item in cart, visits the pages that has been already visited by user A , will give cache hit , with item in cart

Best regards,

• This reply was modified 3 years, 7 months ago by qtwrk.

Hi,

How can I crawl my site with different “vary” ? What means this term regarding of your plugin ?

And additional question, is there a way to identify if a request is coming from the public or the private cache, because I think I have another problem on my site: with a TTL of 1 week for public cache it seem that I am not served anymore from cache after a night… (i am not logged and nothing on my cart)

Best regards

Hi,

unfortunately the crawler is unable to crawl “varied page”

for your second question , please check this guide

Best regards,

Hello @qtwrk

Thanks for the reply.

Regarding the cart not considered as an ESI block, You said earlier :

this feature may requires theme to be compatible with it

Can’t I do something in the theme itself to have the cart compatible ?

If ESI is off, customers with or without something in the cart are served from public cache (x-lsadc-cache: hit), and the cart is working.
But if I activate ESI, customers with something in the cart are no more being served from public cache (x-lsadc-cache: miss) whereas the pages are cached without something in the cart.

Thanks again for the help !

Best Regards

Hi,

since you are using ajax, yo don’t need to bother with that part

if I activate ESI, customers with something in the cart are no more being served from public cache (x-lsadc-cache: miss)

this is what I have been trying to explain from the beginning

you will have 2 sets of public cache , one with cart vary , one without it

in simpler words , all users with empty cart , will see “public cache A” , and all users with item in cart , will see “public cache B”

e.g.

user A , empty cart -> visit page -> cache timestamp 00:00

user B , empty cart -> visit page -> cache timestamp 00:00 , same cache as user A

user C , empty cart -> visit page -> cache timestamp 00:00 , same cache as user A

then , user A add something in cart

user A , with item in cart -> visit page -> cache timestamp 00:10

at this moment , user A has triggered and generated page with cart vary , so , when user B , add item in cart

user B , item in cart -> will see the page with timestamp 00:10 that is generated by user A with item in cart

by now , there are 2 sets of public caches , one , with cart empty , generated at 00:00 , and this set will be given to users with empty cart

another one , with item in cart , generated at 00:10 , and this set will be given to the users with item in carts

Hello @qtwrk,

Let me try to sum up.

If I have an ajax cart, I do not have to care if litespeed is compatible or not with the theme cart as it will always be? So it is normal that I don’t see near my cart html what you mentionned above :
<!-- Block generated by LiteSpeed Cache 3.6 on 2021-04-27 23:21:29 --><!-- lscwp STOREFRONT_CART_HEADER esi end -->

If that’s a yes, it is normal to have the behaviour you mentionned above : the need to have 2 vary depending of the cart state ? (because I see this behaviour only if ESI is on. If it’s off, independently of the cart empty or not, user is served from the same cache, so why it has to be different with ESI on as the cart is ajax ?)

If that’s a yes, and it’s the way litespeed work, needing 2 cache depending of the cart content, how can I enable some vary like you said ? Where can I set that in the plugin ?

Thanks a lot again for your time and help,

Best regards

• This reply was modified 3 years, 7 months ago by amauryt.

Hi,

yes , since you are using ajax cart.

yes , it’s normal you see that behavior with ESI , because it takes it same way for ajax and non-ajax cart

well, you can’t , the plugin will automatically handle it , it’s hard coded

Best regards,

Hello @qtwrk,

Thank you for you answers, it’s clear now.

Just too bad that the crawler can’t crawl those vary :), maybe on a later update :).

Thanks again,

BR

Hi,
I think we have the same issue.
Please read this in Litespeed Cache Slack Channel #wpcache
https://golitespeed.slack.com/archives/C3RJHNBTQ/p1617444393117600

Right now I use a temporary hack to solve this.
wp-content/plugins/litespeed-cache/thirdparty/woocommerce.cls.php
Around row 187 comment //$vary[ ‘woo_cart’ ] = 1;

/**
 * Keep vary on if cart is not empty
 *
 * @since  1.7.2
 * @access public
 */
public function vary_maintain( $vary )
{
	if ( $this->vary_needed() ) {
		do_action( 'litespeed_debug', '(thirdparty/woocommerce.cls.php) API: 3rd woo added vary due to cart not empty' );
		//$vary[ 'woo_cart' ] = 1; // Do not set Cookie 
	}

	return $vary;
}