ieee ccgrid may 22, 20021 the gsoap toolkit robert van engelen kyle gallivan florida state...

IEEE CCGrid May 22, 2002 1

The gSOAP ToolkitRobert van Engelen

Kyle Gallivan

Florida State University


Overview

Web Services gSOAP design and implementation Results Conclusions


Web Services:the Big Picture

SOAP RPC

SOAPDSIGWSDLUDDI


SOAP

Light-weight protocol based on XML as the marshalling format for data in request and response messages Vendor- and platform-neutral Language-neutral Object-model-neutral Transport-neutral

XML allows data transformation (XSLT) XML enables long-term data persistence


WSDL

Web Service registers with UDDI

Web Service publishes WSDL

Clients can develop proxies from the WSDL for SOAP RPC and messaging


gSOAP

Open source (C, C++, and Java) >2000 registered users Uses a source-to-source stub and

skeleton compiler to automate the integration of SOAP RPC in applications Automates the deployment of (legacy)

C/C++ applications as Web Services Automates the development of clients

Suitable for high-performance computing


gSOAP Goals

Application-centric Minimize application code adaptation Support (de)marshalling of application’s

native data structures in SOAP/XML Preserve the logical structure of data

Minimize data migration overhead and formatting errors Avoid (hand-written) wrappers Generate fast (de)marshalling routines

and streaming XML parsers Efficient run-time remote object allocation


The gSOAP Stub and Skeleton Compiler Generates source code stubs and

skeletons for SOAP RPC Generates XML (de)marshalling

routines for native and user-defined C/C++ data types

The gSOAP runtime provides low-level HTTP, TCP, SOAP/XML handling and memory management capabilities

HTTP/TCP/SOAPand XML API

Stub/Skeleton andMarshalling Code

User application

Runtime Library

gSOAP-generated


Development

ServiceApplication

gSOAP-generatedSkeleton Routines

gSOAP-generatedRequest Dispatcher

Specification ofData Types and

Remote Proceduresin C/C++ Header File

gSOAPCompiler

Server

WSDL IDL


Development

Specification ofData Types and

Remote Proceduresin C/C++ Header File

gSOAP-generatedStub Routines

Client Application

Client

WSDL IDL

gSOAP


Example

Service description (WSDL):Namespace: urn:xmethods-delayed-quotes Method name: getQuoteInput parameter: symbol of type xsd:stringOutput parameter: result of type xsd:float

Generated remote procedure declaration for stub generation with gSOAP:ns__getQuote(char *symbol, float &result);

Client code:main(){ float q; if (soap_call_ns__getQuote(“URL”, “”, “AOL”, q) == 0) cout << “AOL: “ << q << endl;}


Encoding C/C++ Data Types in XML Primitive C/C++ types, enum,

struct/class with single inheritance, pointers, arrays, special types (e.g. base64)

Not supported: unions, void*, templates, multiple inheritance


Serialization

gSOAP generates serialization routines for application types

Serialization code traverses object graph at run time to detect co-referenced objects and cycles

Serialization code outputs object graph in XML according to SOAP encoding rules


Serialization Examplestruct BG{ int val; struct BG *left; struct BG *right;}; <BG>

<val>1</val> <left> <val>2</val> <right href=“#X”/> </left> <right href=“#X”/></BG><id id=“X”> <val>3</val> <right href=“#X”/></id>

1

2

3


Deserialization

gSOAP generates deserialization code, including schema-driven XML pull parser Auto-validating Streaming Fast: match inbound XML elements to

“expected” elements in the schema Keep table with “forward” XML refs

Back-patching method: resolve forward refs later by copying pointers and/or referenced data


Deserialization Example

1

2

3

<BG> <val>1</val> <left> <val>2</val>

</left> <right href=“#X”/></BG><id id=“X”> <val>3</val> <right href=“#X”/></id>

<right href=“#X”/>


Results

1. Interoperability testing

2. Legacy code integration

3. Scalability and performance


Interoperability Testing

WhiteMesa.org “interop lab”

Suite of test cases designed for real-time interoperability testing over the Web

Apache Axis, .NET, Delphi,…

String Integer Float Struct String Array

Integer Array

Float Array

Struct Array

Void Base64 Date Hex Binary

Decimal Boolean Map Map Array

gSOAP PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS

SOAP::Lite PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS FAULT

Apache 2.2 PASS PASS PASS PASS FAULT PASS FAULT FAULT PASS PASS PASS PASS PASS PASS PASS PASS

Apache Axis PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS FAIL FAULT PASS PASS PASS PASS

ASP .NET PASS PASS PASS PASS FAIL PASS PASS FAIL PASS PASS PASS FAULT PASS PASS N/A N/A

Cape Connect

PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS N/A N/A

Delphi PASS PASS PASS PASS FAIL PASS PASS FAULT PASS PASS PASS PASS PASS PASS N/A N/A

easySOAP++ PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS N/A N/A

eSOAP PASS PASS PASS PASS FAIL PASS PASS FAIL PASS PASS PASS PASS PASS PASS N/A N/A

Frontier PASS PASS PASS PASS FAULT FAULT FAULT FAULT PASS PASS FAIL FAULT FAULT FAULT N/A N/A

GLUE PASS PASS PASS PASS FAIL PASS PASS FAIL PASS PASS FAIL PASS PASS PASS N/A N/A

MS SOAP 3.0

PASS PASS PASS PASS FAULT PASS FAULT FAULT PASS PASS FAIL PASS PASS PASS N/A N/A

nuSOAP PASS PASS PASS PASS FAIL PASS PASS FAIL PASS PASS PASS PASS PASS PASS FAULT FAULT

OpenLink Virtuoso

PASS PASS PASS PASS FAIL PASS PASS FAIL PASS PASS PASS PASS PASS PASS N/A N/A

PEAR SOAP PASS PASS PASS PASS FAIL PASS PASS FAIL PASS PASS FAULT PASS FAIL PASS FAULT FAULT

SOAP4R PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS

Spheon jSOAP

PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS

Spray PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS N/A N/A

SQLData PASS PASS PASS PASS PASS PASS FAULT FAULT PASS PASS PASS PASS PASS PASS N/A N/A

WASP Adv. PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS N/A N/A

White Mesa PASS PASS PASS PASS FAULT PASS FAULT PASS PASS PASS PASS PASS PASS PASS N/A N/A

XMLBus PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS PASS N/A N/A

4S4C 2.0 PASS PASS PASS PASS PASS PASS FAULT PASS PASS PASS FAULT FAULT PASS PASS N/A N/A


Legacy Code Example:Linear System Solver

Application code from Numerical Recipes in C

Web Service: LU

Decomposition Backsubstitution Solve Multi-solve Matrix inversion


Linear System SolverOriginal Numerical Recipes in C routine:

ludcmp(double **a, int n, int *indx, double *d){ … sum = a[i][j]; … }

Modified routine (array size n stored in class instances):ludcmp(matrix *a, ivector *indx, double *d){ … sum = a[i][j]; … }

C++ class declarations for the generation of (de)serializers with gSOAP:class vector{ double *__ptr; // pointer to array of double int __size; // run-time array size double& operator[](int i);}; class matrix{ vector *__ptr; // pointer to array of vectors int __size; // run-time array size double& operator[](int i);};


Linear System Solver

Remote procedure declaration for stub and skeleton generation with gSOAP:ns__ludcmp( matrix *a, // input matrix struct ns__ludcmpResponse { matrix *a; // output matrix ivector *i; // output index reordering vector double d; // output parameter for determinant } *result)

Remote procedure SOAP server interface routine called by skeleton:ns__ludcmp(matrix *a, struct ns__ludcmpResponse &result){ result.a = a; // input to output matrix if (ludcmp(result.a, result.i, &result.d) != 0) return SOAP_FAULT; return SOAP_OK;}


Linear System Solver

Linear system solver server code (CGI-based):main(){ soap_serve(); // process request (skeletons)}

Example client code:main(){ struct ns__ludcmpResponse result; matrix a; … if (soap_call_ns__ludcmp(“URL”, “”, &a, &result) != 0) soap_print_fault(stderr); …}


Scalability and Performance Scalability and overhead of

communication vs. computation LU-based matrix inversion

Performance (send 32bit int matrix) Full SOAP XML-encoded matrix SOAP Base64-encoded matrix CGI-based SOAP Web Service Stand-alone SOAP Web Service Java RMI


Matrix Inversion

Stand-alone linear system solver service (TCP sockets)

Full double fp. matrix representation in SOAP XML

Total time of client request and server response (10BaseT, Dual PIII 550MHz, Red Hat Linux)


CGI-Based Web Service


SOAP XML-encoded 32bit int matrix

SOAP Base64-encoded 32bit int matrix


Stand-Alone Serviceand Java RMI


SOAP XML-encoded 32bit int matrix

SOAP Base64-encoded 32bit int matrix

Java RMI (1.2.2)


Conclusions

Application centric SOAP/XML Web Service interoperable Legacy numerical code integration Scalability and performance Future work:

IDL DIME Performance enhancements Peer-to-peer networks

ieee ccgrid may 22, 20021 the gsoap toolkit robert van engelen kyle gallivan florida state...

Documents