Working with Page Caching

The Page Cache is used to speed-up recurring executions of PHP scripts in your application. This is achieved by caching the PHP output (HTML) for specific URLs on first execution, to reuse the cached data for subsequent calls. Cache behavior is defined using a flexible rule system that allows you to maintain the dynamic capabilities of your applications.

The following procedure describes how to create a new cache rule. Click here to see how to create a copy of a caching rule.

Instructions on how to complete a procedure

To create a new caching rule:

  1. In the UI, go to Caching | Page Cache.

  2. Select the Rules tab.
  3. From the Request Rules tab, click Create new Rule. You do not need to select the application from here unless you wish to edit the rules associated with that application.
    The New/ Edit Caching Rules page is displayed.

  4. In the General Details area, enter the following information:

    • Application - Select the application to be associated with the caching rule. If the rule belongs to the Global Rules group, this field cannot be edited.
    • Rule Name - Name the new caching rule. Make sure the name is descriptive and easy to remember: This name will appear in the Rules list.

    Note:

    The same rule name cannot be used for two separate applications.

    • Cache Duration - Set the cache duration in seconds. After that time, the cache is refreshed and a newer version is created.
  5. In the Cache Conditions tab, enter the following information:
    1. Define the URL that you want to cache by selecting from the drop-down menu and typing in the entry fields. A URL can be an exact URL or a representation of a pattern of URLs using Regular Expressions.

    Example 1:

    This representation sets the Page Cache to cache the URL http://www.zend.com/index only.

    Example 2:

    Any URL that matches this pattern is cached.

    1. After defining the URL conditions, you can further pinpoint what to cache by adding parameter conditions.
      Click to add a condition, and use the drop-down menus and entry fields to define the condition.

    Example:

    How can we configure the system to use only cached content when a user is not logged in?
    Usage Scenario: Web sites (e.g., portals, news sites, forums) that provide different content to premium users and non-registered users.
    Assuming that the _SESSION 'username' parameter is used to store the name of a currently logged in user, create a rule based on this parameter, as follows:

    This sets the Page Cache to cache content only when the _SESSION parameter 'username' is not set. Subsequently, users that do have the _SESSION 'username' set are presented with a live version of the page.
    If necessary, we can extend this limit to include all users whose 'username' _SESSION parameter equals 'guest' as follows:

  6. In the Multiple Versions tab, enter the following information:
    1. By default, the Create a single cached page check-box is selected.
      To create different cached copied according to specific values, select the Create a separate cached page for each value of the following queries, click , and enter the details of the queries.

    Example:

    The following example demonstrates how to create different copies of cached information, based on the _GET parameter 'language'. This sets Caching to create a different copy for each different value of _GET 'language' (for the content that was cached based on the rules defined in step 4).

    This example demonstrates how to use Caching for multilingual pages that handle the same content in different languages.

  7. Click Save.
    The rule is saved and added to the Rules list.

To edit a rule, go to Caching | Page Cache, select the application that the rule belongs to, and click next to the rule you want to edit.

To clear the information in the cache for a specific rule, go to Caching | Page Cache, select the application the rule belongs to, select the rule you want to clear, and click Clear Cache.

The following procedure describes how to create a new rule based on an already existing rule. This option can be used when a new rule with settings similar to an existing rule needs to be created such as for different URLs with the same caching requirements.

To duplicate a caching rule:

  1. In the UI, go to Caching | Page Cache.

  2. Select the application that the rule belongs to.

  3. In the rule groups list, locate the rule you wish to duplicate and click the rule link.
    The New/ Edit Caching Rules page is displayed.

  4. In the Action bar, click .
    The New/Edit Rule page is displayed again.

  5. Name and configure the duplication, and click .
    The rule is saved and added to the Rules list.

The following procedure describes how to remove a caching rule.

To remove a caching rule:

  1. In the UI, go to Caching | Page Cache.

  2. Select the relevant rule group and the caching rule you wish to remove, and in the Action bar, click .
    The rule is deleted.

The following procedure describes how to clear the cache for a caching rule.

To clear rule cache:

  1. In the UI, go to Caching | Page Cache.

  2. Select the relevant rule group and the caching rule you wish to clear the cache for, and in the Action bar, click .
    The cache is cleared.
    -OR-
    Click to clear the entire cache.

The following procedure describes how to configure the Zend Page Cache component.

Instructions on how to complete a procedure

To configure the component:

  1. In the UI, go to Administration | Components.
  2. From the Components list, select the component.
    The Expanded view will display the directives associated with the component.
  3. Review the assorted directives and their descriptions, and configure the component according to your personal preferences. For information on how to configure directives, see Working with Components.
  4. In the Action bar, click Save.

  5. In the toolbar, the restart icon lights up , indicating a restart is needed to apply changes. Click to restart server and apply changes.
    For information on restarting in Zend Server, see Server Restart.

For information on configuring the component daemon directives, see Configuring Component Daemon Directives (Zend Session Clustering, Zend Deployment, Zend Java Bridge, Zend Job Queue, and Zend Monitor).

The following procedure describes how to create a new response rule.

Instructions on how to complete a procedure

To create a response rule:

  1. In the UI, go to Caching | Page Cache.
  2. Select the Rules tab.
  3. From the Rules tab, select the Reponse Rules tab.
  4. Enter the status code you want to cache in the Cache only if the Response Code one of field.
  5. Select the conditions under which you want to cache the response code:
    • Header name
    • Conditional drop-down — equals, exists, does not equal, does not exist, matches (regex>, does not match (regex).
    • Variable
  6. Select Add Condition to add the condition. You can add multiple conditions.
  7. If you want to delete a condition, select the icon next to the condition.
  8. Click Save.