The web provides both authors and consumers with a far-reaching platform for sharing and using a variety of information, including geography and maps. Information systems are moving from a client/server to a webcentric pattern for implementation. Through their exposure to and use of rich information on the web and the use of new, elegant interfaces provided by companies like Apple, enterprise users want a similar experience when they work with their operational information in their organizations. They want an experience that is simple and intuitive.
A new series of open web standards for the sharing of map services follow "RESTful" design patterns that maximize opportunities for adoption and use. This enables developers and application builders to combine and mash up ArcGIS services with any other web information coming from many different sources. It also gives consumers access to the tremendous wealth of geographic knowledge created in GIS environments.
Through the use of RESTful services and web interfaces, ArcGIS facilitates open information sharing and integration. This ensures that the choice of authoring platform is in no way constrained by the intended audience of the map service, because the standard provides open interchange of information between a wide range of authoring tools and end-user applications. This pattern leverages information delivery to web browsers, phones, tablets, and desktops using a common web pattern that consumers of this information have come to expect.
A map service is a protocol for serving data from GIS databases and other sources to mobile and web clients. A map service is more than just a geographic dataset—it's a combination of data and parameters for defining and delivering a dynamic, interactive, intelligent map.
The GeoServices REST Specification provides a standard way for web clients to communicate with GIS servers. Clients issue requests to the server through structured URLs. The server responds with map images, text-based geographic information, or other resources that satisfy the request.
REST stands for Representational State Transfer. It's an architecture designed for sharing information through the use of simple HTTP protocols. Applications compatible with REST are often referred to as RESTful. Most new APIs follow some form of RESTful design pattern to maximize adoption and ease of use.
As creators of maps and other geographic content, users' information can reside in its native format where it is created while simultaneously being published for consumption in nonnative applications. Publishing map services using an open standard ensures the widest possible distribution of work. Developers of applications can engineer those applications to consume open map services, giving end users access to use and mash up collections of map services unmatched in both quantity and richness.
Developers can make their applications RESTful using popular client-side development environments with the ArcGIS Web Mapping application programming interfaces for JavaScript, Flex, Silverlight, iOS, and Android, all of which incorporate the GeoServices REST Specification. When map services are published using this open standard, anyone can access and leverage them using a simple URL, regardless of the system originally used to create them—users simply provide the map's URL, and the web or mobile app retrieves the map. And the map is not just a static layer; it is an interactive, intelligent map. Users can pan and zoom and, depending on the functionality built into the map, do other things, such as get pop-up feature information, edit and add new features to the map, run spatial analyses, or animate the map to display change through time—all from a simple HTTP request.
ArcGIS Server includes a services directory that allows users to browse the services and functions on their servers using REST. They can also access the services directory in a web browser using http://<server name>/<instance name>/rest/services.
Shared web maps and services can be published and discovered in the Gallery section (arcgis.com/home/gallery.html) of ArcGIS.com.
A growing number of application developers are adopting this standard for publishing open map services. In Esri's ArcGIS product family, users can publish map services that comply with the GeoServices REST Specification.
This is not just a method for sharing work over the web; users can also manage enterprise information in this context. When publishing an open map service, they decide just how private they want it to be—private, semiprivate, or public—item by item. They can control whether the service will be protected behind a firewall or publicly available over the Internet to everyone or just to selected users.
Open map services give GIS professionals many new opportunities to share their geographic knowledge. As geographic knowledge created in GIS environments is increasingly being made available as intelligent web maps, consumer and commercial awareness of geospatial capabilities has grown tremendously. As awareness of and demand for these maps increase, geographic knowledge is becoming embedded in every device and is changing our way of thinking. The work being done by GIS professionals in creating geographic knowledge has never been more important or appreciated.
For more information and to download the GeoServices REST Specification, visit esri.com/opengeoservices.