phptal:cache
This attribute causes output of entire element (including its tag) to be cached on disk and not re-evaluated until cache expires.
Use of cache is beneficial only for elements that use very complex expressions, macros from external files or PHP expressions/objects that access the database. Otherwise uncached templates will be just as fast.
Content of this attribute is a duration (how long element should be kept in cache) written as number with '
d
', '
h
', '
m
' or '
s
' suffix.
<div class="footer" phptal:cache="3h">…</div>
<div>
will be evaluated at most once per 3 hours.
Duration can be followed by optional "
per
" parameter that defines how cache should be shared. By default cache is shared between all pages that use that template. You can add "
per url
" to have separate copy of given element for every
URL.
<ol id="breadcrumbs" phptal:cache="1d per url">…</ol>
<ol>
will be cached for one day, separately for each page.
You can add "
per expression
" to have different cache copy for every different value of an expression (which MUST evaluate to a string).
Expression cannot refer to variables defined using
tal:define
on the same element.
<ul id="user-info" phptal:cache="25m per object/id">…</ul>
<ul>
will be cached for 25 minutes, separately for each object ID.
Be careful when caching users' private data. Cache will be shared with everyone unless you make it user-specific with
per user/id
or similar expression.
Instead of clearing cache, it might be a better idea to put version or last modification timestamp in the
per
parameter. This will cause cached template to be refreshed as soon as version/timestamp changes and no special cache clearing will be necessary.
<div phptal:cache="100d per php:news.id . news.last_modified_date">…</div>
phptal:cache
blocks can be nested, but outmost block will cache other blocks regardless of their freshness.
You cannot use
metal:fill-slot
inside elements with
phptal:cache
.