1. SOA-40: Getting Rejected on the Bus
How OpenEdge® Developers Deal with Failure
David Cleary
Principal Software Engineer

2. Aristotle – Greek philosopher
“It is possible to fail in many ways… while to succeed is possible in only one way”
Aristotle – Greek philosopher
SOA-40: Getting Rejected on the Bus

3. OpenEdge and Sonic™ ESB
You can align business and IT goals using Sonic and OpenEdge in your SOA
You can create robust and flexible business applications
You can handle failures in your infrastructure, applications, or data
SOA-40: Getting Rejected on the Bus

4. Agenda Sonic ESB Endpoints Faults and rejected messages
Dealing with rejection on the bus
Sonic ESB Endpoints
Faults and rejected messages
Quality of Service (QOS) and Message Time To Live (TTL)
Application architecture and AppServer™ operating modes
Fault processing options
AppServer Down!!!!
SOA-40: Getting Rejected on the Bus

5. Terminology Service Process Container
Your OpenEdge based application exposed to Sonic ESB through the Sonic Adapter
Process
A Sonic ESB process that uses an itinerary to execute 1 or more operations on 1 or more services
Container
A Sonic managed executable process that hosts processes and services
SOA-40: Getting Rejected on the Bus

6. Sonic ESB Endpoints
Destination where ESB services and processes send and receive messages
Can be associated with a Queue or Topic
4 defined Endpoint types for Services
Entry (required for services)
Exit (usually ReplyTo)
Fault
RME
SOA-40: Getting Rejected on the Bus

7. OpenEdge ESB Adapter Architecture
Entry Endpoint
Fault Endpoint
AppServer
Adapter
Rejected Endpoint
Database
Exit Endpoint
SOA-40: Getting Rejected on the Bus

8. Faults and Rejected Messages
Invalid message types
Invalid data
Adapter exceptions
Failure to send result
Fault Messages
Infrastructure issues
Applications errors (RETURN ERROR)
Service has Fault and Rejected Message endpoints
SOA-40: Getting Rejected on the Bus

9. Anatomy of a Rejected Message
<SOAP-ENV:Body>
<xq:rejectedMessageInfo xmlns:xq=“…">
<rejectedCode>OPENEDGE_INVOCATION_ERROR</rejectedCode>
<rejectedLocation container="dev_OpenEdgeTest"
host="pcdcleary" process="CheckCustomer"
serviceApplication="dev.OpenEdge" step="Find Customer"
topLevelProcess="CheckCustomer"/>
<rejectedDetails>
{Error message and stack trace}
</rejectedDetails>
SOA-40: Getting Rejected on the Bus

10. Anatomy of a Fault Message
<exception xmlns=“…">
<message>Fault String: SessionPool : NoAvailableSessions[Could not connect to the AppServer: General Error: Connection refused: connect. (7203)]</message>
<class>com.progress.open4gl.dynamicapi.SessionPool.NoAvailableSessionsException</class>
<detail>
<faultDetails container="dev_OpenEdgeTest" host="pcdcleary" process="CheckCustomer" serviceApplication="dev.OpenEdge" step="Find Customer" topLevelProcess="CheckCustomer" />
</detail>
<faultDetails container="dev_OpenEdgeTest" host="pcdcleary" process="CheckCustomer" serviceApplication="dev.OpenEdge" step="Find Customer" topLevelProcess="CheckCustomer" />
< message>
Fault String: SessionPool : NoAvailableSessions[Could not connect to the AppServer: General Error: Connection refused: connect. (7203)]
</message>
<class>
com.progress.open4gl.dynamicapi.SessionPool.NoAvailableSessionsException
</class>
SOA-40: Getting Rejected on the Bus

11. Quality of Service Best Effort At Least Once Exactly Once Default
Messages may be lost or redelivered
At Least Once
No lost messages
May be redelivered
Exactly Once
Most reliable
No lost or redelivered messages
SOA-40: Getting Rejected on the Bus

12. Message Time To Live Specifies a timeout on a process
Messages that timeout sent to RME
Default is 0 (no timeout)
SOA-40: Getting Rejected on the Bus

13. Configuring Properties
Service
Fault and Rejected Message endpoints
Can be overridden by process
Endpoint
Entry endpoint specifies QOS
Process sets minimum QOS
Process
Time to Live
SOA-40: Getting Rejected on the Bus

14. Application Architecture and Operating Modes
Sonic container and OpenEdge AppServer treated as single unit
Sonic provides networking
Fewer faults due to AppServer availability
ESB Service and OpenEdge AppService same
Session-free operating mode recommended
Each operation does complete unit of work
No state saved on AppServer
Persistent procedures defeat this architecture
SOA-40: Getting Rejected on the Bus

15. Session-managed and Persistent Procedure Issues
Requires three calls for a single operation
Saves state on AppServer even with Session-free
AppServer still bound due to fault or rejected message
Limits scalability
Enable Intra-Container messaging to mitigate issues
SOA-40: Getting Rejected on the Bus

16. Fault Processing Options
Settable per operation
Fault Only (Default)
Original message lost
Fault and Original message
Original message can be remediated and resubmitted
Rejected and Original message
Same as above, but rejected format
Continue process with Fault
SOA-40: Getting Rejected on the Bus

17. Fault Processing Options
SOA-40: Getting Rejected on the Bus

18. Booking a Vacation Coordinator Service Flight Booking Hotel Booking
Client
Flight Booking
Hotel Booking
Car Booking
SOA-40: Getting Rejected on the Bus

19. Book Hotel Room Process
SOA-40: Getting Rejected on the Bus

20. Checking Availability
Yes, there are rooms available
Process/transaction continues
No, there are not rooms available
Entire transaction fails
I don’t know if rooms are available
AppServer down
No available agents
SOA-40: Getting Rejected on the Bus

21. Fix problem and resubmit
SOA-40: Getting Rejected on the Bus

22. AppServer Down Demo!!!
SOA-40: Getting Rejected on the Bus

23. Agenda Sonic ESB Endpoints Faults and rejected messages
Dealing with rejection on the bus
Sonic ESB Endpoints
Faults and rejected messages
Quality of Service (QOS) and Message Time To Live (TTL)
Application architecture and AppServer operating modes
Fault processing options
AppServer Down!!!!
SOA-40: Getting Rejected on the Bus

24. In Summary
You can align business and IT goals using Sonic and OpenEdge
You can create robust and flexible business applications
You can handle failures in your infrastructure, applications, or data
SOA-40: Getting Rejected on the Bus

25. For More Information, go to…
PSDN
Introducing Native Invocation with the OpenEdge Adapter for Sonic ESB
Progress Sonic ESB Developers Guide - Resubmit Sample
Progress eLearning Community:
OpenEdge Development with Sonic ESB
Designing ESB Processes
Orchestrating Services with Sonic BPEL Server
SOA-40: Getting Rejected on the Bus

26. Relevant Exchange Sessions
SOA-11: Common Applications for Sonic ESB
SOA-23: Enterprise Integration Patterns in Sonic ESB
SOA-30: Getting the Most Out of Sonic Workbench
SOA-33: Transactions in an SOA World
SOA-40: Getting Rejected on the Bus

27. ?
Questions
SOA-40: Getting Rejected on the Bus

28. Thank You
SOA-40: Getting Rejected on the Bus

29. SOA-40: Getting Rejected on the Bus