Smallworld GeoSpatial Server provides all the critical functionality to provide and consume services for Smallworld-based applications, as well as packages of services provided in extension modules.
Providing Web Services
GeoSpatial Server’s Service Provider functionality provides robust Magik-based services accessing a Smallworld VMDS database. It is designed to deploy on a server farm using load balancing to distribute service requests to achieve highly scalable systems.
- GSS uses common web service frameworks for defining services (SOAP Web Services via HTTP or JMS) and for securing message level security in accordance with WS Security standards and using Transport level security using SSL. These are deployable on industry standard Oracle® WebLogic, IBM® Websphere® and JBoss® application servers.
- At runtime, browser-based remote administration is provided to allow the simple management of servers by administrators.
- Developers are supported in writing new services by a suite of examples and documentation.
Consuming Web Services
In order to take part in business processes, a Smallworld application may be required to call, or consume, external web services that provide information to the Smallworld environment. For example, integrating with a Work Management System typically requires both consuming and providing web services. GSS supports the interaction with other systems using its service consumer capability that includes:
- A Magik Service Consumer API for Web Service calls
- Java™ Virtual Server which handles requests from service consumers
- Business Services that represent Web Service calls
- Web Service request infrastructure based on Axis2
As an extensible platform, GSS has a set of extension modules that provide packages of services (or service endpoints in the case of service consumer functionality). A common set of business services are provided with the base GSS product. The following are the additional extension modules shipped with GeoSpatial Server 4.3:
- Open Services Extension Module - provides a suite of OGC web services. Priced separately.
- INSPIRE Extension - provides an e - a set of stateless services for building web applications.
Customers and partners can expand this with extension modules of their own; guidance and an example is provided with the product.
Smallworld GeoSpatial Server provides an Open Services Extension Module that provides OGC implementing support and fully certified services.
Web Mapping Service - WMS
- Certified support for OGC WMS 1.3
- GetMap, GetCapabilities and GetFeatureInfo operations
- Implementing support for WMS 1.0.0 and WMS 1.1.1
Web Feature Service - WFS
- Certified support for OGC WFS 1.1
- Support for GetCapabilities, DescribeFeatureType, GetFeatureInfo operations
- Provides a standard interface to query database tables, producing a GML 3.1.1 response
- Supports the Filter Encoding Specification version 1.1.0 including:
- Spatial Operators: BBOX, Equals, Disjoint, Intersects, Within, Contains
- Spatial Operands: Envelope, Point, LineString, Polygon
- Logical Operators: And, Or, Not
- Comparison Operators: LessThan, GreaterThan, LessThanEqualTo, GreaterThanEqualTo, EqualTo, NotEqualTo, Between
- Support for HTTP GET and HTTP POST, where the request is sent as an XML document. This enables clients to send complex queries (with complex filter and complex geometry operands) to WFS and also to save them for reuse
Web Coverage Service - WCS
- Certified support for OGC WCS 1.0
- Support for GetCapabilities, DescribeCoverage, GetCoverage operations
OGC Geography Markup Language (GML)
- The default response format for geospatial data is GML 3.1.1 extended with Smallworld annotation text geometry type
- All Common GSS Business Services that return features (Query Service, Select Service, etc.) use the GML 3.1.1 format as default
- The OGC WMS.GetFeatureInfo() operation also returns GML 3.1.1
- Join feature properties can be output as XLink references, which enable a client to request the joined records through their URN
Java Implementation of OGC Specifications
- Feature model including collections of features and a feature schema
- Geometry model conforms to the Simple Features specification, extended with oriented points, annotation text and curves
Extension Module for INSPIRE
This extension module provides a set of web services that give support for organizations wanting to comply with the European “INfrastructure for SPatial InfoRmation in Europe” (INSPIRE) initiative.
The GSS extension module for INSPIRE contains web services to provide language specific capabilities documents and to provide maps using a web mapping service that uses coordinate systems and language parameters as specified by the INSPIRE View Service technical implementing guidance.
Also provided in the extension module are examples of the metadata required for INSPIRE:
- Service metadata that enables the discovery of spatial data services and describes their capabilities
- Dataset metadata that enables the discovery and evaluation of spatial data by search criteria
The example metadata files can be used as templates for organizations developing their own metadata and can be used to provide capabilities documents in different languages. A scenario is provided that shows how the open source tool GeoNetwork can be used to manage the metadata.
REST Services Extension Module
The REST services extension module provides support for stateless web services. This allows many of the existing GSS business services to be accessed without any state information and for new services to be added to GSS that are declared and managed as REST services. The key advantage of REST services are in the use of web applications that work using responses to plain URLs without maintaining state information between requests.