SCA C++, C and COBOL

1. www.oasis-open.org SCA C++, C and COBOL Bryan Aupperle David Haney 18 Sept. 2007

2. OASIS Status • C and C++ specifications transitioning from OSOA to OASIS • Governed by the SCA-C-C++ TC • Policy related annotations • Cross standard consistency • Compliance test suites • COBOL specification continuing development under OSOA • SCA-C-C++ TC work will influence

3. SCDL for C++ • interface.cpp • header – C++ header file describing the interface • class – (optional) Class defining the interface • callbackHeader – (optional) C++ header describing the callback interface • callbackClass – (optional) Class defining the callback interface • remotable – (optional) • implementation.cpp • library – Shared library defining the service factory • path – (optional) Path to search for the library • header – C++ header file describing the implementation • class – (optional) Class defining the implementation • scope – (optional)

4. C++ APIs • ComponentContext • Primary interface for accessing SCA defined components. • Component Meta Information • getCurrent(), getURI(), getProperties(), getDataFactory() • Service Lookup • getService(), getServices() • Service References • getServiceReference(), getServiceReferences() • getSelfReference()

5. C++ APIs (cont) • ServiceReference • Interface for interacting with service instances • Conversational interface • getConversationID(), setConversationID() • Asynchronous interface • getCallbackID(), setCallbackID() • getCallback(), setCallback()

6. C++ WSDL Mapping • Defines a translation from a C++ class interface to a WSDL • Uses comment annotations to control the conversion • Defines mapping rules for: • primitive types • C++ Standard Library types • SDO • classes, structs, arrays, enums • Defers to the OMG WSDL to C++ Mapping for generating C++ headers from a WSDL.

7. SCDL for C • Interface defined by a set of functions • interface.c • header – header file describing the interface • callbackHeader – (optional) header file describing the callback interface • remotable – (optional) • implementation.c • module – binary executable for the component implementation • library – (optional) indicates whether the service is implemented as a library or a program • location – (optional) location of the module • scope – (optional)

8. C APIs • Synchronous Programming • SCALocate(), SCALocateMultiple() – get handle(s) to services • SCAInvoke() – invokes an operation of a service • SCAProperty<PropertyType>() – get the value of a property • SCAGetFaultMessage(), SCASetFaultMessage() – get or set a fault message for a service operation • Asynchronous Programming • SCAGetCallback() – get handle of callback instance • SCACallback() – invoke a callback operation • SCASetCallback() – set a callback function for a reference • SCASetCallbackID(), SCAGetCallbackID() – get or set the callback ID for a service instance • Conversation Services • SCAGetConversationID(), SCASetConversationID() – get or set a user provided conversation ID • SCAEndConversation() – end a conversation

9. Implementation as Program • Support environments where function is provided by programs • API • SCAService() – get name of invoked service • SCAOperation() – get name of invoked operation • SCAMessageIn() – get input message SCAMessageOut() – set output message

10. SCDL for COBOL • interface.cobol • copybook – copybook file describing the interface • callbackCopybook – (optional) copybook file that describing the callback interface • location – (optional) location of library containing the copybook files • remotable – (optional) • implementation.cobol • program –binary executable for the component implementation • location – (optional) location of library containing the binary executable • scope – (optional)

11. COBOL APIs • Same functions as in C • Synchronous Programming • SCAProperty is not typed • Program-Based Implemenation Support • Asynchronous Programming • Conversation Services

12. C & COBOL WSDL Mapping • Defines a translation between language structures and WSDL • Defines type mapping rules for: • Primitive types • Structs or Groups • SDO • Variable length strings and unbounded arrays • Defines mapping rules between operations and functions

13. Annotations • Contained in comments, processed by tools • Interface • Invocation attribute • OneWay • Remotable • Callback • EndConversation • Implementation • Scope • Lifecycle • Conversation information • Property • Reference

14. Open Implementations • Apache Tuscany Native • http://incubator.apache.org/tuscany/sca-native.html • Implements pre-1.0 C++ specification • Working towards 1.0 compliance

15. OASIS References • SCA-C-C++ TC • http://www.oasis-open.org/apps/org/workgroup/sca-c-cpp/description.php • SCA-C-C++ Charter • http://www.oasis-open.org/committees/sca-c-cpp/charter.php

16. OSOA References • OSOA SCA Specifications • http://www.osoa.org/display/Main/Service+Component+Architecture+Specifications • Final Specifications • SCA C++ Client and Implementation • Draft Specifications • SCA C Client and Implementation • SCA COBOL Client and Implementation

17. Other References • OMG WSDL to C++ Specification • http://www.omg.org/docs/ptc/06-08-01.pdf

18. Backup

19. C++ APIs (cont) • Supplemental APIs • RefCountingPointer • Defines a reference-counted pointer interface • SCAException • Provides a hierarchy of exception classes for use with the SCA API. • SCANullPointerException • ServiceRuntimeException • ServiceUnavailableException • NoRegisteredCallbackException • ConversationEndedException • MultipleServicesException

20. C++ Annotations • Contained in comments, processed by tools • Interface Header File • @Remotable • @Callback • @OneWay • @EndConversation • Implementation Header File • @Scope • @EagerInit • @AllowsPassByReference • @Conversation • @Property • @Reference

21. C Annotations • Contained in comments, processed by tools • Header File • @Operation, @Callback • @Remotable, @OneWay • @EndConversation • Implementation File • @Service • @Reference • @Property • @Scope • @Init, @Destroy, @EagerInit • @AllowPassByReference • @Conversation

22. COBOL Annotations • Contained in comments, processed by tools • Interface File • @Operation, @Callback • @Remotable, @OneWay • @EndConversation • Implementation File • @Service • @Reference • @Property • @Scope • @Init, @Destroy, @EagerInit • @AllowPassByReference • @Conversation

23. C++ Example • Interface SCDL <service name=“LoanService”> <interface.cpp header=“LoanService.h”/> </service> • Implementation SCDL <component name=“LoanServiceImpl”> <implementation.cpp library=“loan” header=“LoanServiceImpl.h”/> </component>

24. C++ Example (cont) • LoanService Interface class LoanService { public: virtual bool approveLoan( unsigned long customerNumber, unsigned long loanAmount) = 0; };

25. C++ Example (cont) • LoanServiceImpl Interface class LoanServiceImpl :public LoanService { public: virtual bool approveLoan( unsigned long customerNumber, unsigned long loanAmount) { // … } };

26. C++ Example (cont) • SCA Application int main(void) { ComponentContextPtr context = ComponentContext::getCurrent(); LoanService* service = (LoanService*) context->getService(“loanService”); bool result = service->approveLoan(12345, 100); }