13 Sending Invalidation Requests

Invalidation in Hierarchies

In a configuration with a hierarchy of OracleAS Web Cache servers, it is likely that content will be cached on multiple servers.

Figure 13-1 depicts a distributed cache hierarchy. A central cache is located in the United States office, and a remote cache is located in the Japan office. While the central cache stores content from an application Web server, the remote cache stores content from the central cache. In other words, the central cache acts as an origin server to the remote cache in Japan.

When an invalidation message is sent to the central cache to refresh content, the central cache automatically propagates the invalidation message to the remote cache in Japan to ensure consistency.

Figure 13-1 Scenario 1: Invalidating Content in a Distributed Cache Hierarchy

Description of "Figure 13-1 Scenario 1: Invalidating Content in a Distributed Cache Hierarchy"

Figure 13-2 depicts an ESI cache hierarchy. A subscriber cache performs Edge Side Includes (ESI) assembly. Provider caches locally cache ESI fragments for ESI provider sites www.providersite1.com and www.providersite2.com. During ESI page assembly, the subscriber cache contacts the provider caches for the ESI fragments.

Figure 13-2 Scenario 2: Invalidating Content in an ESI Cache Hierarchy

Description of "Figure 13-2 Scenario 2: Invalidating Content in an ESI Cache Hierarchy"

When an invalidation message is sent to a central or provider cache to refresh content, the central or provider cache automatically propagates the invalidation message to the remote or subscriber cache to ensure consistency.

To ensure that the central or provider cache only invalidates its content, the remote or subscriber cache checks the site host name specified in the invalidation message with the IP address of the provider cache from which the invalidation message was propagated. If there is a match, the remote or subscriber cache processes the invalidation request. Otherwise, the request is rejected. For distributed cache hierarchies, the site host name for the central and remote caches should be configured to be identical, making a mismatch unlikely.

Invalidation in Cache Clusters

In a cache cluster, administrators can decide whether to propagate invalidation messages to all cache cluster members or to send invalidation messages individually to cache cluster members.

When OracleAS Web Cache propagates invalidation messages, the cache that received the invalidation request acts as the invalidation coordinator for that request. The coordinator propagates the invalidation messages to the other cluster members. The coordinator waits for responses from all cluster members. When the propagation completes, the coordinator returns a message to the sender that lists, for each cluster member, the cluster member name, the status of the invalidation request, and the number of objects invalidated.

If any cluster member cannot be reached, OracleAS Web Cache returns an error message and does not propagate the invalidation messages.

During a cache cluster upgrade, you upgrade one cache cluster member at a time. The caches will continue to respond to requests. However, because other cluster members have a different version of the configuration, the caches will not forward invalidation messages to those cache cluster members operating with a different version. Instead, if the requested object is not cached by that cache or by cluster members with the same version of the configuration, OracleAS Web Cache forwards the request to the origin server.

When the cache cluster members are not running the same version of OracleAS Web Cache, you can still invalidate objects, and you can propagate the invalidation to other cluster members, but the invalidation message must originate from the cache that is operating with the earlier version of OracleAS Web Cache.

Invalidation Request Syntax

Use the following syntax to invalidate objects contained within an exact URL that includes the complete path and file name:

<?xml version="1.0"?>
<!DOCTYPE INVALIDATION SYSTEM "internal:///WCSinvalidation.dtd">
<INVALIDATION VERSION="WCS-1.1">
   <SYSTEM>
    <SYSTEMINFO NAME="name" VALUE="value"/>
   </SYSTEM>  
   <OBJECT>
     <BASICSELECTOR URI="URL"/>
     <ACTION REMOVALTTL="TTL"/>
     <INFO VALUE="value"/>
   </OBJECT>
</INVALIDATION>

Use the following syntax to invalidate objects based on more advanced invalidation selectors:

<?xml version="1.0"?>
<!DOCTYPE INVALIDATION SYSTEM "internal:///WCSinvalidation.dtd">
<INVALIDATION VERSION="WCS-1.1">
   <SYSTEM>
    <SYSTEMINFO NAME="name" VALUE="value"/>
   </SYSTEM>  
   <OBJECT>
     <ADVANCEDSELECTOR URIPREFIX="prefix"
                       URIEXP="URL_expression"
                       HOST="host_name:port"
                       METHOD="HTTP_request_method"
                       BODYEXP="HTTP_body"/>
       <COOKIE NAME="cookie_name" VALUE="value"/>
       <HEADER NAME="HTTP_request_header" VALUE="value"/>
       <OTHER NAME="URI|BODY|QUERYSTRING_PARAMETER|SEARCHKEY"
             TYPE="SUBSTRING|REGEX"
             VALUE="value"/>
     </ADVANCEDSELECTOR>
     <ACTION REMOVALTTL="TTL"/>
     <INFO VALUE="value"/>
   </OBJECT>
</INVALIDATION>

The body of a valid invalidation request must begin with the following:

<?xml version="1.0"?>
<!DOCTYPE INVALIDATION SYSTEM "internal:///WCSinvalidation.dtd">

The first line denotes version 1.0 of XML. The second line denotes that the request is an invalidation request using the WCSinvalidation.dtd file as the XML document type. WCSinvalidation.dtd is the Document Type Definition (DTD) that defines the grammar of invalidation requests and responses.

Note the following:

• No white space is allowed before "<?xml".

• If an application is sharing invalidation requests with a third-party XML parser, replace "internal:///WCSinvalidation.dtd" with the following path:

  "http://www.oracle.com/webcache/90400/WCSinvalidation.dtd"
  
  

The root element INVALIDATION contains one or more of the attributes and elements described in Table 13-1.

[13/Jul/2005:19:26:46 +0000] [notification 11748] [invalidation] [ecid: 21085932167,0] Invalidation with INFO 'INFO_comment' has returned with status 'status'; number of objects invalidated: 'number'.

<?xml version="1.0"?>
<!DOCTYPE INVALIDATION SYSTEM "internal:///invalidation.dtd">
<INVALIDATION>
   <URL EXP="URL" PREFIX="YES|NO">
               <VALIDITY LEVEL="validity" REFRESHTIME="seconds"/>
               <COOKIE NAME="cookie_name" 
                       VALUE="value"   
                       NONEXIST="YES|NO"/>
               <HEADER NAME="HTTP_request_header" VALUE="value"/>
   </URL>
</INVALIDATION>

Invalidation Response Syntax

Invalidation responses are returned in the following format for BASICSELECTOR invalidation requests:

<?xml version="1.0"?> 
<!DOCTYPE INVALIDATIONRESULT SYSTEM "internal:///WCSinvalidation.dtd">
<INVALIDATIONRESULT VERSION="WCS-1.1">
   <SYSTEM>
     <SYSTEMINFO NAME="name" VALUE="value"/>
   </SYSTEM>  
   <OBJECTRESULT>
     <BASICSELECTOR URI="URL">
     </BASICSELECTOR>
     <RESULT ID="ID" STATUS="status" NUMINV="number"/>
     <INFO VALUE="value"/>
   </OBJECTRESULT>
</INVALIDATIONRESULT>

Invalidation responses are returned in the following format for ADVANCEDSELECTOR invalidation requests:

<?xml version="1.0"?> 
<!DOCTYPE INVALIDATIONRESULT SYSTEM "internal:///WCSinvalidation.dtd">
<INVALIDATIONRESULT VERSION="WCS-1.1">
   <SYSTEM>
     <SYSTEMINFO NAME="name" VALUE="value"/>
   </SYSTEM>  
   <OBJECTRESULT>
    <ADVANCEDSELECTOR URIPREFIX="prefix"
                      URIEXP="URL_expression"
                      HOST="host_name:port"
                      METHOD="HTTP_request_method"
                      BODYEXP="HTTP_body"/>
      <COOKIE NAME="cookie_name" VALUE="value"/>
      <HEADER NAME="HTTP_request_header" VALUE="value"/>
      <OTHER NAME="URI|BODY|QUERYSTRING_PARAMETER|SEARCHKEY"
             TYPE="SUBSTRING|REGEX"
             VALUE="value"/>
     </ADVANCEDSELECTOR>
     <RESULT ID="ID" STATUS="status" NUMINV="number"/>
     <INFO VALUE="value"/>
   </OBJECTRESULT>
</INVALIDATIONRESULT>

The body of a valid invalidation response begins with the following:

<?xml version="1.0"?>
<!DOCTYPE INVALIDATIONRESULT SYSTEM "internal:///WCSinvalidation.dtd">

The first line denotes version 1.0 of XML. The second line denotes the response is an invalidation response using the WCSinvalidation.dtd file as the XML document type.

The root element INVALIDATIONRESULT contains one or more of the attributes and elements described in Table 13-2. BASICSELECTOR and ADVANCEDSELECTOR are described in Table 13-1.

Invalidation Preview Request Syntax

To test invalidation, use the following syntax to preview the list of BASICSELECTOR objects to be invalidated:

<?xml version="1.0"?>
<!DOCTYPE INVALIDATIONPREVIEW SYSTEM "internal:///WCSinvalidation.dtd">
<INVALIDATIONPREVIEW VERSION="WCS-1.1" STARTNUM="start_number" MAXNUM="max_number">
     <BASICSELECTOR URI="URL"/>
</INVALIDATIONPREVIEW>

Use the following syntax to preview the list of ADVANCEDSELECTOR objects to be invalidated:

<?xml version="1.0"?>
<!DOCTYPE INVALIDATIONPREVIEW SYSTEM "internal:///WCSinvalidation.dtd">
<INVALIDATIONPREVIEW VERSION="WCS-1.1" STARTNUM="start_number" MAXNUM="max_number">
    <ADVANCEDSELECTOR URIPREFIX="prefix"
                      URIEXP="URL_expression"
                      HOST="host_name:port"
                      METHOD="HTTP_request_method"
                      BODYEXP="HTTP_body"
      <COOKIE NAME="cookie_name" VALUE="value"/>
      <HEADER NAME="HTTP_request_header" VALUE="value"/>
      <OTHER NAME="URI|BODY|QUERYSTRING_PARAMETER|SEARCHKEY"  
             TYPE="SUBSTRING|REGEX"
             VALUE="value"/>
    </ADVANCEDSELECTOR>
</INVALIDATIONPREVIEW>

The body of a valid invalidation preview request must begin with the following:

<?xml version="1.0"?>
<!DOCTYPE INVALIDATIONPREVIEW SYSTEM "internal:///WCSinvalidation.dtd">

The first line denotes version 1.0 of XML. The second line denotes the request is an invalidation preview request using the WCSinvalidation.dtd file as the XML document type.

The root element INVALIDATIONPREVIEW contains one or more of the attributes described in Table 13-3. BASICSELECTOR and ADVANCEDSELECTOR are described in Table 13-1.

Invalidation Preview Response Syntax

Invalidation preview responses for preview requests are returned in the following format:

<?xml version="1.0"?> 
<!DOCTYPE INVALIDATIONPREVIEWRESULT SYSTEM "internal:///WCSinvalidation.dtd">
<INVALIDATIONPREVIEWRESULT VERSION="WCS-1.1" STATUS="status" NUMURLS="number" TOTALNUMURLS="total_number">
   <SELECTURL VALUE="URL">
   </SELECTEDURL>
</INVALIDATIONPREVIEWRESULT>

The body of a valid invalidation preview response begins with the following:

<?xml version="1.0"?> 
<!DOCTYPE INVALIDATIONPREVIEWRESULT SYSTEM "internal:///WCSinvalidation.dtd">

The first line denotes version 1.0 of XML. The second line denotes that the response is an invalidation preview response using the WCSinvalidation.dtd file as the XML document type.

Note the following:

• No white space is allowed before "<?xml".

• If an application is sharing invalidation requests with a third-party XML parser, replace "internal:///WCSinvalidation.dtd" with the following path:

  "http://www.oracle.com/webcache/90400/WCSinvalidation.dtd"
  
  

The root element INVALIDATIONPREVIEWRESULT contains one or more of the attributes and elements described in Table 13-4. BASICSELECTOR and ADVANCEDSELECTOR are described in Table 13-1.

Submitting Basic Invalidation Requests

To send a basic invalidation request using OracleAS Web Cache Manager:

1. In the navigator frame, select Operations > Basic Content Invalidation.

   The Basic Content Invalidation page appears in the right pane.

2. From the For Cache list, select a cache. (More than one cache is listed only if you configured a cache cluster. If you configured the cluster to propagate invalidation, the cache you select is designated the invalidation coordinator, which will propagate the invalidation request to other cache cluster members. If you did not configure the cluster to propagate invalidation, the cache you select is the only cache from which objects are invalidated.)

3. In the Search Criteria section, select the search criteria:

   • Remove all cached objects: Select to remove all objects from the cache.

   • Enter exact URL for removal: Specify the URL of the objects to be invalidated. Include the complete path and file name.

     Note: Because OracleAS Web Cache escapes the following characters, you can enter them in this field: ampersand (&), greater than sign (>), less than sign (<), double quotes ("), and single quotes (').

4. Optionally, you can preview the list of objects to be invalidated to ensure that you are removing only the objects you want to remove. To preview the list of objects:

   1. In the Action section, choose Preview list of objects that match invalidation criteria.

   2. Specify the Object Range:

      • From: Enter the number representing the first object to be listed. OracleAS Web Cache begins the count of objects with the number 0.

      • To: Enter the number of objects to be listed.

        If fewer objects than the number specified meet the invalidation criteria, OracleAS Web Cache lists the URLs for only those objects that meet the criteria.

        If more objects than the number specified meet the invalidation criteria, OracleAS Web Cache lists the URLs for the number of objects requested. It also returns the total number of objects that meet the invalidation criteria. To obtain the list of URLs for addition objects, send another preview request with a different From number that specifies the start of the next set of objects.

   3. Click Submit.

      OracleAS Web Cache displays the Invalidation Preview Results message box, which lists the objects that meet the invalidation criteria. OracleAS Web Cache Manager lists only those objects that are valid. Although the cache may contain objects that are expired or that have been invalidated, those objects are not listed.

      If the objects listed are those that you want to invalidate, continue with the next step. If they are not, modify the invalidation criteria and preview the list again.

5. In the Action section, select one of the following options to specify how to process invalid objects:

   • Remove immediately: OracleAS Web Cache marks objects as invalid and removes them immediately. A object is refreshed from the origin server when the cache receives the next request for it.

   • Remove objects no later than <number> <time> after submission: OracleAS Web Cache marks objects as invalid and then refreshes them based on origin server capacity. Enter the maximum time in which the objects can reside in the cache.

     
     

     Note: Performance assurance heuristics apply when you configure objects to be refreshed based on when the origin servers can refresh them; performance assurance heuristics do not apply when objects are immediately removed.

     
     

6. Click Submit.

OracleAS Web Cache processes the invalidation request, and returns the Cache Cleanup Result dialog box that the shows the invalidation status and the number of objects invalidated. The following figure shows the dialog box:

In a cache cluster environment, if Propagate Invalidation is enabled, OracleAS Web Cache sends the invalidation request to one cluster member who acts as the invalidation coordinator. The coordinator propagates the invalidation request to other cluster members. When the invalidation has been completed for all cluster members, OracleAS Web Cache returns a Cache Cleanup box, that lists, for each cluster member, the cache name, the status of the invalidation request, and the number of objects invalidated.

Submitting Advanced Invalidation Requests

To send an advanced invalidation request using OracleAS Web Cache Manager:

1. In the navigator frame, select Operations > Advanced Content Invalidation.

   The Advanced Content Invalidation page appears in the right pane.

2. From the For Cache list, select a cache. (More than one cache is listed only if you configured a cache cluster.)

3. In the Search Criteria section, select the search criteria:

   
   

   Note: Because OracleAS Web Cache escapes the following characters, you can enter them in the search criteria fields: ampersand (&), greater than sign (>), less than sign (<), double quotes ("), and single quotes (').

   
   

   • URL Path Prefix: Required. Specify the path prefix of the objects to be invalidated. The path prefix must begin with http|https://host_name:port/path/filename or with "/" and end with "/".

     host_name:port is optional. You can also specify the site host name and port in the Host Name field.

     The prefix is interpreted literally, including reserved regular expression characters. These characters include periods (.), question marks (?), asterisks (*), brackets ([]), curly braces ({}), carets (^), dollar signs ($), and backslashes (\).

   • Host Name: Optional. Specify the host name and port number of the site (host_name:port). Port 80 is the default port for HTTP.

     This field is required if the URL Path Prefix does not include http|https://host_name:port/path/filename.

   • HTTP Method: Optional. Select the HTTP request method (GET or POST) of the objects to be invalidated. The default value is GET.

   • URL Expression: Optional. Specify the URL of the objects to be invalidated under the URL Path Prefix. Then, specify how to match by selecting either substring for an exact string match or regular expression for a regular expression match.

     If no value is entered, everything under the URL Path Prefix is matched.

   • POST Body Expression: Optional. If POST is selected for the HTTP Method, enter the HTTP POST body of the objects to be invalidated, and then specify how to match by selecting either substring for a substring string match or regular expression for a regular expression match.

     
     

     Note: If regular expression is selected for the URL Expression or POST Body Expression fields, OracleAS Web Cache interprets the following reserved regular expression characters: periods (.), question marks (?), asterisks (*), brackets ([]), curly braces ({}), carets (^), dollar signs ($), and backslashes (\). To interpret these characters literally, escape them with a backslash (\).

     
     

4. Optionally, in the Cookie/Header Information section, specify the use of cookie names or HTTP request headers used for multiple-version objects in the search criteria:

   1. From the list, select Cookie or Header.

   2. Provide the following information:

      • Cookie: Enter the cookie name used by multiple-version objects to be invalidated in the Name field, and enter its value in the Value field.

        
        

        Note: If you specify a cookie that was mistakenly specified for both a multiple-version object and a session caching policy, invalidation is based on any occurrence of the cookie. To avoid excessive invalidation, configure distinct cookies for multiple-version objects (Rules for Caching, Personalization, and Compression > Cookie Definitions) and session caching policies (Rules for Caching, Personalization, and Compression > Session Definitions).

        
        

      • Header: Enter the HTTP request header used by the objects to be invalidated in the Name field, and enter its value in the Value field.

   
   

   See Also: "Task 1: Create Caching Rules" to create caching rules for multiple-version objects

   
   

5. Optionally, in the URL Parameters section, enter the name of the embedded URL parameter used by the objects to be invalidated in the Name field, enter its value in the Value field, and then specify how to match by selecting either exact strings or regular expression.

6. Optionally, in the Search Keys section, enter the name of a search key from the Surrogate-Key response-header field used by the objects to be invalidated in the Key field.

   
   

   See Also: "Surrogate-Key Response-Header Field"

   
   

7. Optionally, you can preview the list of objects to be invalidated to ensure that you are removing only the objects you want to remove. To preview the list of objects:

   1. In the Action section, choose Preview list of objects to be removed.

   2. Specify the Object Range:

      • From: Enter the number representing the first object to be listed. OracleAS Web Cache begins the count of objects with the number 0.

      • To: Enter the number of objects to be listed.

      If fewer objects than the number specified meet the invalidation criteria, OracleAS Web Cache lists the URLs for only those objects that meet the criteria.

      If more objects than the number specified meet the invalidation criteria, OracleAS Web Cache lists the URLs for the number of objects requested. It also returns the total number of objects that meet the invalidation criteria. To obtain the list of URLs for addition objects, send another preview request with a different From number that specifies the start of the next set of objects.

   3. Click Submit.

      OracleAS Web Cache displays the Invalidation Preview Results message box, which lists the objects that meet the invalidation criteria. OracleAS Web Cache Manager lists only those objects that are valid. Although the cache may contain objects that are expired or that have been invalidated, those objects are not listed.

      If the objects listed are those that you want to invalidate, continue with the next step. If they are not, modify the invalidation criteria and preview the list again.

8. In the Action section, select one of the following options to specify how to process invalid objects:

   • Remove immediately: OracleAS Web Cache marks objects as invalid and then removes them immediately. A object is refreshed from the origin server when the cache receives the next request for it.

   • Remove objects no later than <number> <time> after submission: OracleAS Web Cache marks objects as invalid and then refreshes them based on origin server capacity. Enter the maximum time in which the objects can reside in the cache.

     
     

     Note: Performance assurance heuristics apply when you configure objects to be refreshed based on when the application Web servers can refresh them; performance assurance heuristics do not apply when objects are immediately removed.

     
     

9. Click Submit.

OracleAS Web Cache processes the invalidation request, and returns a Cache Cleanup dialog box that the shows the invalidation status and the number of objects invalidated.

Example: Invalidating One Object

The following request invalidates the file /images/logo.gif:

<?xml version="1.0"?>
<!DOCTYPE INVALIDATION SYSTEM "internal:///WCSinvalidation.dtd">
<INVALIDATION VERSION="WCS-1.1">
   <OBJECT>
     <BASICSELECTOR URI="http://www.company.com:80/images/logo.gif"/>
     <ACTION/>
   </OBJECT>
</INVALIDATION>

Invalidation response:

<?xml version="1.0"?> 
<!DOCTYPE INVALIDATIONRESULT SYSTEM "internal:///WCSinvalidation.dtd">
<INVALIDATIONRESULT VERSION="WCS-1.1">
   <OBJECTRESULT>
     <BASICSELECTOR URI="http://www.company.com:80/images/logo.gif"/>
     <RESULT ID="1" STATUS="SUCCESS" NUMINV="1"/>
     </OBJECTRESULT>
</INVALIDATIONRESULT>

The following request invalidates an object exactly matching /contacts/contacts.html using the BASICSELECTOR element:

<?xml version="1.0"?>
<!DOCTYPE INVALIDATION SYSTEM "internal:///WCSinvalidation.dtd">
<INVALIDATION VERSION="WCS-1.1">
  <OBJECT>
    <BASICSELECTOR URI="http://www.company.com:80/contacts/contacts.html"/>
    <ACTION REMOVALTTL="0"/>
  </OBJECT>
</INVALIDATION>
    

This request is equivalent to the following request using the ADVANCEDSELECTOR element. This request specifies the site information in the HOST attribute.

<?xml version="1.0"?>
<!DOCTYPE INVALIDATION SYSTEM "internal:///WCSinvalidation.dtd">
<INVALIDATION VERSION="WCS-1.1">
  <OBJECT>
    <ADVANCEDSELECTOR URIPREFIX="/contacts/" URIEXP="^/contacts/contacts\.html$" HOST="www.company.com:80"/>
    <ACTION REMOVALTTL="0"/>
  </OBJECT>
</INVALIDATION>

The second request specifies the site information in the URIPREFIX attribute:

<?xml version="1.0"?>
<!DOCTYPE INVALIDATION SYSTEM "internal:///WCSinvalidation.dtd">
<INVALIDATION VERSION="WCS-1.1">
  <OBJECT>
    <ADVANCEDSELECTOR URIPREFIX="http://www.company.com/contacts/" URIEXP="^/contacts/contacts\.html$"/>
    <ACTION REMOVALTTL="0"/>
  </OBJECT>
</INVALIDATION>
    

The ADVANCEDSELECTOR element uses the URIPREFIX attribute. This attribute is used to traverse the directory structure. The quicker invalidation reaches the right tree level, the quicker the invalidation process is done. The request with the BASICSELECTOR element is the more efficient of the two examples because there is no directory structure traversal involved.

Example: Invalidating Multiple Objects

The following request invalidates two different objects, summary.jsp and summary.gif. In addition, the request provides the comments "summary.jsp" and "summary.gif" to be included in the invalidation result and event log.

<?xml version="1.0"?>
<!DOCTYPE INVALIDATION SYSTEM "internal:///WCSinvalidation.dtd">
<INVALIDATION VERSION="WCS-1.1">
  <OBJECT>
    <ADVANCEDSELECTOR URIPREFIX="/global/sales/" URIEXP="summary.jsp\?year=2001" HOST="www.company.com:80"/>
      <COOKIE NAME="group" VALUE="asia"/>
    </ADVANCEDSELECTOR>
    <ACTION />
    <INFO VALUE="summary.jsp"/>
  </OBJECT>
  <OBJECT>
    <ADVANCEDSELECTOR URIPREFIX="/image/" URIEXP="summary.*\.gif$" HOST="www.company.com:80"/>
    <INFO VALUE="summary.gif"/>
    <ACTION />
  </OBJECT>
</INVALIDATION>

Invalidation response:

<?xml version="1.0"?> 
<!DOCTYPE INVALIDATIONRESULT SYSTEM "internal:///WCSinvalidation.dtd">
<INVALIDATIONRESULT VERSION="WCS-1.1">
  <OBJECTRESULT>
    <ADVANCEDSELECTOR URIPREFIX="/global/sales/" URIEXP="summary.jsp\?year=2001" HOST="www.company.com:80"/>
      <COOKIE  NAME="group"  VALUE="asia"  />
    </ADVANCEDSELECTOR>
    <RESULT ID="1" STATUS="SUCCESS" NUMINV="2"/>
    <INFO VALUE="summary.jsp"/>
  </OBJECTRESULT>
  <OBJECTRESULT>
    <ADVANCEDSELECTOR URIPREFIX="/image/" URIEXP="summary.*\.gif$" HOST="www.company.com:80"/>
    </ADVANCEDSELECTOR>
    <RESULT ID="2" STATUS="SUCCESS" NUMINV="14"/>
    <INFO VALUE="summary.gif"/>
  </OBJECTRESULT>
</INVALIDATIONRESULT>

The following messages are written to the event log:

[13/Jul/2005:19:26:46 +0000] [notification 11748] [invalidation] [ecid:
 21085932167,0] Invalidation with INFO 'summary.jsp' has returned with status
 'SUCCESS'; number of objects invalidated: '2'.
.
.
.
[13/Jul/2005:19:26:46 +0000] [notification 11748] [invalidation] [ecid:
 21085932167,0] Invalidation with INFO 'summary.gif' has returned with status
 'SUCCESS'; number of objects invalidated: '14'.

Example: Invalidating a Subtree of Objects

The following request invalidates all objects under the /images/ directory:

<?xml version="1.0"?>
<!DOCTYPE INVALIDATION SYSTEM "internal:///WCSinvalidation.dtd">
<INVALIDATION VERSION="WCS-1.1">
   <OBJECT>
     <ADVANCEDSELECTOR URIPREFIX="/images/" HOST="www.company.com:80"/>
     <ACTION REMOVALTTL="0"/>
   </OBJECT>
</INVALIDATION>

Invalidation response:

<?xml version="1.0"?> 
<!DOCTYPE INVALIDATIONRESULT SYSTEM "internal:///WCSinvalidation.dtd">
<INVALIDATIONRESULT VERSION="WCS-1.1">
   <OBJECTRESULT>
     <ADVANCEDSELECTOR URIPREFIX="/images/" HOST="www.company.com:80"/>
     <RESULT ID="1" STATUS="SUCCESS" NUMINV="125"/>
   </OBJECTRESULT>
</INVALIDATIONRESULT>

The following request invalidates all objects under the /contacts/ directory whose file names end in .html and uses cookie name cust with a value of oracle:

<?xml version="1.0"?>
<!DOCTYPE INVALIDATION SYSTEM "internal:///WCSinvalidation.dtd">
<INVALIDATION VERSION="WCS-1.1">
  <OBJECT>
    <ADVANCEDSELECTOR URIPREFIX="/contacts/" URIEXP="\.html$" HOST="www.company.com:80"/>
      <COOKIE NAME="cust" VALUE="oracle"/>
    </ADVANCEDSELECTOR>
    <ACTION REMOVALTTL="0"/>
  </OBJECT>
</INVALIDATION>

Invalidation response:

<?xml version="1.0"?> 
<!DOCTYPE INVALIDATIONRESULT SYSTEM "internal:///WCSinvalidation.dtd">
<INVALIDATIONRESULT VERSION="WCS-1.1">
   <OBJECTRESULT>
     <ADVANCEDSELECTOR URIPREFIX="/contacts"/> URIEXP="\.html$" HOST="www.company.com:80"/>
      <COOKIE NAME="cust" VALUE="oracle"/>
     </ADVANCEDSELECTOR>
      <RESULT ID="1" STATUS="SUCCESS" NUMINV="45"/>
   </OBJECTRESULT>
</INVALIDATIONRESULT>

Example: Invalidating All Objects for a Web Site

The following request invalidates all objects under /.

<?xml version="1.0"?>
<!DOCTYPE INVALIDATION SYSTEM "internal:///WCSinvalidation.dtd">
<INVALIDATION VERSION="WCS-1.1">
   <OBJECT>
     <ADVANCEDSELECTOR URIPREFIX="/" HOST="www.company.com:80"/>
     <ACTION REMOVALTTL="0"/>
   </OBJECT>
</INVALIDATION>

Invalidation response:

<?xml version="1.0"?> 
<!DOCTYPE INVALIDATIONRESULT SYSTEM "internal:///WCSinvalidation.dtd">
<INVALIDATIONRESULT VERSION="WCS-1.1">
   <OBJECTRESULT>
     <ADVANCEDSELECTOR URIPREFIX="/" HOST="www.company.com:80"/>
      <RESULT ID="1" STATUS="SUCCESS" NUMINV="17"/>
   </OBJECTRESULT>
</INVALIDATIONRESULT>

Example: Invalidating Objects Using Prefix Matching

To better understand the relationship of the URIPREFIX and URIEXP attributes, consider the examples that follow.

The following syntax invalidates sample.gif files within the /cec/cstage/graphic* directories:

<ADVANCEDSELECTOR URIPREFIX="/cec/cstage/"
   URIEXP="graphic.*/sample\.gif">
</ADVANCEDSELECTOR>

Note that ".*" in "graphic.*/sample\.gif" are regular expression characters that match all directories starting with graphic. The "." in "sample\.gif" is escaped for a literal interpretation.

The following syntax instructs OracleAS Web Cache to locate a directory named graphic*:

<ADVANCEDSELECTOR URIPREFIX="/cec/cstage/graphic*/" URIEXP="sample\.gif" HOST="www.company.com:80"/>
</ADVANCEDSELECTOR>

The following syntax invalidates objects contained within /cec/cstage?ecaction=viewitem:

<ADVANCEDSELECTOR URIPREFIX="/cec/" URIEXP="cstage\?ecaction=viewitem" HOST="www.company.com:80"/>
</ADVANCEDSELECTOR>

Note that "?" is escaped with a backslash.

URLs such as /cec/cstage?ecaction=viewitem&zip=94405 and /cec/cstage?ecaction=viewitem&zip=94305 match and are invalidated, but /usa/cec/cstage?ecaction=viewitem&zip=94209 does not match and is not invalidated.

Example: Invalidating Objects Using Substring and Query String Matching

The following request invalidates all objects under / matching the substrings /post/ and htm. In addition, the request provides the comment "remove-htm-under-all-post-dir" to be included in the invalidation result and event log.

<?xml version="1.0"?>
<!DOCTYPE INVALIDATION SYSTEM "internal:///WCSinvalidation.dtd">
<INVALIDATION VERSION="WCS-1.1">
  <OBJECT>
    <ADVANCEDSELECTOR URIPREFIX="/"
                      HOST="www.company.com:80">
      <OTHER NAME="URI" TYPE="SUBSTRING" VALUE="/post/"/>
      <OTHER NAME="URI" TYPE="SUBSTRING" VALUE="htm"/>
    </ADVANCEDSELECTOR>
    <ACTION REMOVALTTL="0" />
    <INFO VALUE="remove-htm-under-all-post-dir"/>
  </OBJECT>
</INVALIDATION>

Invalidation response:

<?xml version="1.0"?> 
<!DOCTYPE INVALIDATIONRESULT SYSTEM "internal:///WCSinvalidation.dtd">
<INVALIDATIONRESULT VERSION="WCS-1.1">
   <OBJECTRESULT>
     <ADVANCEDSELECTOR URIPREFIX="/" HOST="www.company.com:80"/>
       <OTHER NAME="URI" TYPE="SUBSTRING" VALUE="/post/"/>
       <OTHER NAME="URI" TYPE="SUBSTRING" VALUE="htm"/>      
      <RESULT ID="1" STATUS="SUCCESS" NUMINV="52"/>
      <INFO VALUE="remove-htm-under-all-post-dir"/>
   </OBJECTRESULT>
</INVALIDATIONRESULT>

The following message is written to the event log:

[13/Jul/2005:19:26:46 +0000] [notification 11748] [invalidation] [ecid:
 21085932167,0] Invalidation with INFO 'remove-htm-under-all-post-dir has
 returned with status 'SUCCESS'; number of objects invalidated: '12'.

The following request invalidates all objects under /corporate/asp/, matching the substring /view_building.asp and the embedded URL parameter value pairs of building=8 and floor=10. In addition, the request provides the comment "remove-view-building8-10th-floor" to be included in the invalidation result and event log.

<?xml version="1.0"?>
<!DOCTYPE INVALIDATION SYSTEM "internal:///WCSinvalidation.dtd">
<INVALIDATION VERSION="WCS-1.1">
  <OBJECT>
    <ADVANCEDSELECTOR URIPREFIX="/corporate/asp/"
                      HOST="www.company.com:80">
      <OTHER NAME="URI" TYPE="SUBSTRING" VALUE="/view_building.asp"/>
      <OTHER NAME="QUERYSTRING_PARAMETER" TYPE="SUBSTRING" VALUE="building=8"/>
      <OTHER NAME="QUERYSTRING_PARAMETER" TYPE="SUBSTRING" VALUE="floor=10"/>
    </ADVANCEDSELECTOR>
    <ACTION REMOVALTTL="0" />
    <INFO VALUE="remove-view-building8-10th-floor"/>
  </OBJECT>
</INVALIDATION>

Invalidation response:

<?xml version="1.0"?> 
<!DOCTYPE INVALIDATIONRESULT SYSTEM "internal:///WCSinvalidation.dtd">
<INVALIDATIONRESULT VERSION="WCS-1.1">
   <OBJECTRESULT>
     <ADVANCEDSELECTOR URIPREFIX="/" HOST="www.company.com:80"/>
       <OTHER NAME="URI" TYPE="SUBSTRING" VALUE="/view_building.asp"/>
       <OTHER NAME="QUERYSTRING_PARAMETER" TYPE="SUBSTRING" VALUE="building=8"/>
       <OTHER NAME="QUERYSTRING_PARAMETER" TYPE="SUBSTRING" VALUE="floor=10"/>     
      <RESULT ID="1" STATUS="SUCCESS" NUMINV="3"/>
      <INFO VALUE="remove-view-building8-10th-floor"/>
   </OBJECTRESULT>
</INVALIDATIONRESULT>

The following message is written to the event log:

[13/Jul/2005:19:26:46 +0000] [notification 11748] [invalidation] [ecid: 21085932
167,0] Invalidation with INFO 'remove-view-building8-10th-floor' has returned with status 'SUCCESS'; number of objects invalidated: '3'.

Example: Invalidating Objects Using Search Key Matching

The following request invalidates all objects under /pls/publicuser/, matching the following:

• Substring /pls/publicuser/!MODULE.wwpob_page.show

• HTTP request header x-oracle-cache-user and value PUBLICUSER

• Surrogate-Key response-header field containing a search key of template_id=33,31345.

<?xml version="1.0"?>
<!DOCTYPE INVALIDATION SYSTEM "internal:///WCSinvalidation.dtd">
<INVALIDATION VERSION="WCS-1.1">
<OBJECT>
    <ADVANCEDSELECTOR URIPREFIX="/pls/publicuser/" HOST="www.company.com:80"
      METHOD="POST">
      <OTHER NAME="SEARCHKEY" VALUE="template_id=33,31345"/>
      <HEADER NAME="x-oracle-cache-user" VALUE="PUBLICUSER"/>
      <OTHER NAME="URI" TYPE="SUBSTRING"
        VALUE="/pls/publicuser/!MODULE.wwpob_page.show"/>
    </ADVANCEDSELECTOR>
    <ACTION REMOVALTTL="0"/>
</OBJECT>
</INVALIDATION>

Invalidation response:

<?xml version="1.0"?> 
<!DOCTYPE INVALIDATIONRESULT SYSTEM "internal:///WCSinvalidation.dtd">
<INVALIDATIONRESULT VERSION="WCS-1.1">
   <OBJECTRESULT>
    <ADVANCEDSELECTOR URIPREFIX="/pls/publicuser/" HOST="www.company.com:80"
      METHOD="POST">
      <OTHER NAME="SEARCHKEY" VALUE="template_id=33,31345"/>
      <HEADER NAME="x-oracle-cache-user" VALUE="PUBLICUSER"/>
      <OTHER NAME="URI" TYPE="SUBSTRING"
        VALUE="/pls/publicuser/!MODULE.wwpob_page.show"/>
      <RESULT ID="1" STATUS="SUCCESS" NUMINV="3"/>
   </OBJECTRESULT>
</INVALIDATIONRESULT>

Example: Propagating Invalidation Requests Throughout a Cache Cluster

In a cache cluster, you can enable or disable the propagation of invalidation requests to all cluster members. You specify the setting from the Cluster Members and Properties page of Application Server Control Console (Web Cache Home page > Administration tab > Cluster Properties > Members and Properties) or the Clustering page (Properties > Clustering) of OracleAS Web Cache Manager.

You can override the setting by using a pair of name/value attributes of the SYSTEMINFO element. If NAME is set to WCS_PROPAGATE and VALUE is set to TRUE, it overrides the setting specified in OracleAS Web Cache Manager. If NAME is set to WCS_PROPAGATE and VALUE is set to FALSE, it reads the setting specified in OracleAS Web Cache Manager.

The following request invalidates the file /images/logo.gif and propagates the request to all cluster members. In this example, there are three cluster members:

<?xml version="1.0"?>
<!DOCTYPE INVALIDATION SYSTEM "internal:///WCSinvalidation.dtd">
<INVALIDATION VERSION="WCS-1.1">
   <SYSTEM>
      <SYSTEMINFO NAME="WCS_PROPAGATE" VALUE="TRUE"/>
   </SYSTEM>
   <OBJECT>
     <BASICSELECTOR URI="/hostname:port/images/logo.gif"/>
     <ACTION/>
   </OBJECT>
</INVALIDATION>

Invalidation response:

<?xml version="1.0"?> 
<!DOCTYPE INVALIDATIONRESULTDETAIL SYSTEM "internal:///WCSinvalidation.dtd">
<INVALIDATIONRESULTDETAIL VERSION="WCS-1.1">
  <INVALIDATIONRESULT VERSION="WCS-1.1">
     <SYSTEM>
       <SYSTEMINFO NAME="WCS_CACHE_NAME" VALUE="Cache_A"/>
     </SYSTEM>
     <OBJECTRESULT>
       <BASICSELECTOR URI="http://www.company.com:80/images/logo.gif"/>
       <RESULT ID="1" STATUS="SUCCESS" NUMINV="1"/>
     </OBJECTRESULT>
  </INVALIDATIONRESULT>
  <INVALIDATIONRESULT VERSION="WCS-1.1">
     <SYSTEM>
       <SYSTEMINFO NAME="WCS_CACHE_NAME" VALUE="Cache_B"/>
     </SYSTEM>
     <OBJECTRESULT>
       <BASICSELECTOR URI="http://www.company.com:80/images/logo.gif"/>
       <RESULT ID="1" STATUS="SUCCESS" NUMINV="1"/>
     </OBJECTRESULT>
  </INVALIDATIONRESULT>
  <INVALIDATIONRESULT VERSION="WCS-1.1">
     <SYSTEM>
       <SYSTEMINFO NAME="WCS_CACHE_NAME" VALUE="Cache_C"/>
     </SYSTEM>
     <OBJECTRESULT>
       <BASICSELECTOR URI="http://www.company.com:80/images/logo.gif"/>
       <RESULT ID="1" STATUS="SUCCESS" NUMINV="1"/>
     </OBJECTRESULT>
  </INVALIDATIONRESULT>
</INVALIDATIONRESULTDETAIL>

Example: Previewing Invalidation

The following request previews up to 50 objects ending in *.htm:

<?xml version="1.0"?>
<!DOCTYPE INVALIDATIONPREVIEW SYSTEM
"internal:///WCSinvalidation.dtd">
<INVALIDATIONPREVIEW VERSION="WCS-1.1" STARTNUM="0" MAXNUM="50">
  <ADVANCEDSELECTOR URIPREFIX="http://company-sun/"
                    URIEXP=".*\.htm" >
  </ADVANCEDSELECTOR>
</INVALIDATIONPREVIEW>

Invalidation response:

"<?xml version="1.0"?>
<!DOCTYPE INVALIDATIONPREVIEWRESULT SYSTEM
"internal:///WCSinvalidation.dtd">
<INVALIDATIONPREVIEWRESULT VERSION="WCS-1.1" STATUS="SUCCESS"
                           STARTNUM="0" NUMURLS="2" TOTALNUMURLS="2">
  <SYSTEM>
    <SYSTEMINFO NAME="WCS_CACHE_NAME" VALUE="server-cache"/>
  </SYSTEM>
  <SELECTEDURL VALUE="/company-sun:80/index.htm "/>
  <SELECTEDURL VALUE="/company-sun:80/dtd.htm "/>
</INVALIDATIONPREVIEWRESULT>