The goal of Reliable Messaging in Web services is to allow applications to send and receive messages in an efficient and reliable manner amidst application, platform, or network failure. The WS-Reliable Messaging specification (WS-RM) defines a protocol and a set of mechanisms that ensure that messages are delivered reliably between two endpoints.
The WSO2 Data Services Server provides a Reliable Messaging tool that is used to enable WS-RM to services at global-level and service-level. If you activate reliable messaging for a particular service, your configurations will be applied to that particular service. WS-Reliable Messaging handles and solves both simple and complex scenarios arising in message transmission.
Follow the instructions below to enable/disable Reliable Messaging in your data service.
1. Log on to the Data Services Server Management Console.
2. Click on Main menu and click List under Web Services.
3. The Deployed Services page appears. Click on the service, for which you want to activate Reliable Messaging.
4. The Service Dashboard page appears. Click Reliable Messaging in the Quality of Service Configuration panel.
The following actions are available:
Enabling Reliable Messaging
Reliable Messaging can be enabled on two levels:
- Service Level (as discussed here)
- Global Level (in the "sandesha2" module)
Follow the instructions below to enable Reliable Messaging on a service level.
5. The Enable Reliable Messaging page appears after clicking Reliable Messaging in the Quality of Service Configuration panel.
Select Yes from the drop-down menu.
6. The current Reliable Messaging Sequence Configuration appears.
Field Descriptions
WS-RM defines a one way sequence. The sender (source) is called the RMS (reliable messaging source) and the receiver (destination) is called the RMD (reliable messaging destination). Therefore for in-out operations, the RM uses two sequences. For request messages the server acts as the RMD and for response messages, the server act as the RMS.
- Inactivity Timeout Interval - The maximum inactive time for any RM session. After the sequence timeout, the RM session is terminated.
- Inactivity Timeout Measure - The unit in which the inactivity timeout interval is specified.
- Sequence Removal Timeout - Shows the interval. If the sequence is inactive during this time period, the sequence is removed from the storage.
- Sequence Removal Timeout Measure - The unit, in which the sequence removal timeout interval is specified.
- Acknowledgment Interval - The time interval that the RMD uses to send the acknowledgments.
- Retransmission Interval - The time interval, after which the RMS retransmits the message if it does not get an acknowledgment.
- ExponentialBackoff - Whether RMS exponentially increases the retransmission time or not.
- Maximum Retransmission Count - The maximum number of retransmits the RMS sends.
7. Modify the configuration if required. Click Finish. Reliable Messaging will be activated for that particular service.
Functions of Buttons:
- Finish - Click "Finish" to submit the current data. When finished, your throttle configuration will be applied and the page will be redirected to the previous page.
- Reset - Click "Reset" to load the last submitted configuration.
- Default - Click "Default" to load the default throttle configuration. If you want to submit those data, you have to click "Finish."
- Clear - Click "Clear" to clear all the text boxes in the UI.
- Cancel - Click "Cancel" to go to the "Deployed Modules" page.
Disabling Reliable Messaging
Execute steps 1 to 4 as shown above.
5. The Enable Reliable Messaging page appears after clicking Reliable Messaging in the Quality of Service Configuration panel.
Select No from the drop-down menu.
6. Confirm your request by clicking Yes.
