7 Configuring Message Buffering for Web Services

The following sections describe how to configure message buffering for Web services.

Overview of Message Buffering
Configuring Messaging Buffering

Overview of Message Buffering

When an operation on a buffered Web service is invoked, the message representing that invocation is stored in a JMS queue. WebLogic Server processes this buffered message asynchronously. If WebLogic Server goes down while the message is still in the queue, it will be processed as soon as WebLogic Server is restarted.

WebLogic Server then processes the request message on a separate thread obtained from a pre-configured and managed pool of threads. This allows WebLogic Server to absorb spikes in client load, and continue to process the requests in an orderly fashion over a period of time. Message buffering is a powerful tool to avoid denial of service attacks and general overload conditions on the server.

To assist you in determining whether to configure message buffering on the Web service, it is recommended that you review Failure Scenarios with Non-buffered Reliable Web Services.

Configuring Messaging Buffering

You can configure message buffering for Web services at the WebLogic Server or Web service endpoint levels. The message buffering configured at the server level defines the default message buffering defined for all Web services and clients running on that server, unless explicitly overridden at the Web service endpoint level.

For detailed steps to configure message buffering for Web services at the WebLogic Server or Web service endpoint level using the WebLogic Server Administration Console, see "Configure message buffering for Web services" in Oracle WebLogic Server Administration Console Help.

When you configure message buffering at the Web service endpoint level, select Customize Buffering Configuration to indicate that you want to customize the buffering configuration defined in the Web service descriptor or deployment plan at the Web service endpoint level. If not checked, the buffering configuration specified at the WebLogic Server level is used.

Alternatively, you can use WLST to configure message buffering. For information about using WLST to extend the domain, see "Configuring Existing Domains" in Oracle WebLogic Scripting Tool.

The following sections describe message buffering configuration properties:

Configuring the Request Queue
Configuring the Response Queue
Configuring Message Retry Count and Delay

Configuring the Request Queue

The following table summarizes the properties used to configure the request queue.

Table 7-1 Configuring the Request Queue

Property	Description
Request Queue Enabled	Flag that specifies whether the request queue is enabled. By default, the request queue is disabled. The request queue name is defined by the logical store enabled at this level. When using a WebLogic Server persistent store as the physical store for a logical store, the names of the request and response buffering queues are taken from the logical store configuration and not the buffering configuration.
Request Queue Connection Factory JNDI Name	JNDI name of the connection factory to use for request message buffering. This value defaults to the default JMS connection factory defined by the server.
Request Queue Transaction Enabled	Flag that specifies whether transactions should be used when storing and retrieving messages from the request buffering queue. This flag defaults to false.

Property

Description

Request Queue Enabled

Flag that specifies whether the request queue is enabled. By default, the request queue is disabled. The request queue name is defined by the logical store enabled at this level.

When using a WebLogic Server persistent store as the physical store for a logical store, the names of the request and response buffering queues are taken from the logical store configuration and not the buffering configuration.

Request Queue Connection Factory JNDI Name

JNDI name of the connection factory to use for request message buffering. This value defaults to the default JMS connection factory defined by the server.

Request Queue Transaction Enabled

Flag that specifies whether transactions should be used when storing and retrieving messages from the request buffering queue. This flag defaults to false.

Configuring the Response Queue

The following table summarizes the properties used to configure the response queue.

Table 7-2 Configuring the Response Queue

Property Description

Property	Description
Response Queue Enabled	Flag that specifies whether the response queue is enabled. By default, the response queue is disabled. The response queue name is defined by the logical store enabled at this level. When using a WebLogic Server persistent store as the physical store for a logical store, the names of the request and response buffering queues are taken from the logical store configuration and not the buffering configuration. Note: This property is ignored if Persistence strategy is set to `IN_MEMORY`.
Response Queue Connection Factory JNDI Name	JNDI name of the connection factory to use for response message buffering. This value defaults to the default JMS connection factory defined by the server.
Response Queue Transaction Enabled	Flag that specifies whether transactions should be used when storing and retrieving messages from the response buffering queue. This flag defaults to false.

Response Queue Enabled

Flag that specifies whether the response queue is enabled. By default, the response queue is disabled. The response queue name is defined by the logical store enabled at this level.

Note: This property is ignored if Persistence strategy is set to IN_MEMORY.

Response Queue Connection Factory JNDI Name

JNDI name of the connection factory to use for response message buffering. This value defaults to the default JMS connection factory defined by the server.

Response Queue Transaction Enabled

Flag that specifies whether transactions should be used when storing and retrieving messages from the response buffering queue. This flag defaults to false.

Configuring Message Retry Count and Delay

The following table summarizes the properties used to configure the message retry count and delay.

Table 7-3 Configuring Message Retry Count and Delay

Property Description

Property	Description
Retry Count	Number of times that the JMS queue on the invoked WebLogic Server instance attempts to deliver the message to the Web service implementation until the operation is successfully invoked. This value defaults to 3.
Retry Delay	Amount of time between retries of a buffered request and response. Note, this value is only applicable when RetryCount is greater than 0. The value specified must be a positive value and conform to the XML schema duration lexical format, `PnYnMnDTnHnMnS`, where `nY` specifies the number of years, `nM` specifies the number of months, `nD` specifies the number of days, `T` is the date/time separator, `nH` specifies the number of hours, `nM` specifies the number of minutes, and `nS` specifies the number of seconds. This value defaults to `P0DT30S` (30 seconds).

Retry Count

Number of times that the JMS queue on the invoked WebLogic Server instance attempts to deliver the message to the Web service implementation until the operation is successfully invoked. This value defaults to 3.

Retry Delay

Amount of time between retries of a buffered request and response. Note, this value is only applicable when RetryCount is greater than 0.

The value specified must be a positive value and conform to the XML schema duration lexical format, PnYnMnDTnHnMnS, where nY specifies the number of years, nM specifies the number of months, nD specifies the number of days, T is the date/time separator, nH specifies the number of hours, nM specifies the number of minutes, and nS specifies the number of seconds. This value defaults to P0DT30S (30 seconds).