Web GISOregon Explorer

Marc G RempelOregon State University The Valley LibraryOregon Explorermarc.rempel@oregonstate.edu

What is the Oregon Explorer?

Natural Resources Digital Library

Place-based resources

Supports informed natural resource decision-making

Evolution of the Oregon Explorer

Basin Portalse.g. Willamette Basin Explorer

Topic Portalse.g. Land Use Explorer

Data Portalse.g. Imagery ExplorerOregon Spatial Data Library

Components of Web GIS

1. Spatial Data2. Web Server3. Map/GIS Server4. Mapping Application5. Application

Enhancements (optional)

MapServer example

Components of Web GIS- Spatial Data

Shapefiles/ Geodatabases (ESRI)

KML/KMZ (Google Earth)

GeoRSS/GeoJson

Web services

WMS – Web Mapping Services (image)

WFS – Web Feature Services (vector)

WCS – Web Coverage Services (raster)

Examples of Spatial Data:

Components of Web GIS- Web Server

Apache Tomcat

IIS (Windows)

Examples of Web Servers:

Web Servers provide the foundation for serving out data on the web.

Components of Web GIS- Map/GIS Servers

ArcIMS

ArcGIS Server

GeoServer

MapServer

Examples of Mapping Servers:

Components of Web GIS- Map/GIS Servers

1. Serve spatial data via the internet.2. When a request comes to the web server, the

Map/GIS server application handles the request and returns a map image, attribute, geometry or downloadable data.

3. The Map/GIS server can also return images of legends, scale bars and reference maps.

4. Requests can query the spatial data and return only the data that matches the request.

5. Some Map/GIS servers also support geometry, geocoding and geo-processing tasks requests. (i.e. buffer queries, clipping, etc).

Role of Map/GIS Servers:

Components of Web GIS- Map/GIS Servers

1. A Map/GIS server can have multiple services of various types. Map service Geoprocessing service Geodata service Image service Geometry service Geocoding service Globe service

2. A map service is a specified grouping of spatial data with projection and display information defined. For ESRI, a .mxd file can serve as the source for a map service.

3. A Map/GIS server can allow for map services to be started and stopped.

4. A map service can support multiple output formats (WMS, WFS, KML)

Map/GIS Server Services

Components of Web GIS- Map/GIS Servers

Map/GIS Server Services: ESRI Example ArcCatalog

Components of Web GIS- Map/GIS Servers

Some Map/GIS Servers expose their services via REST and SOAP APIs.

REST API Representational State Transfer (REST) is a stateless protocol for

leveraging representations of service data and methods.Provides a lightweight interface to access service properties and functionality through client side script.Example: http://methionine.library.oregonstate.edu/ArcGIS/rest/services

SOAP APISimple Object Access Protocol (SOAP) is a protocol for creating server side classes and methods for a web service. SOAP tends to have more robust capability over REST, but can be more complicated to incorporate.Example: http://methionine.library.oregonstate.edu/ArcGIS/services/Restoration/OWRI_07_1/MapServer?wsdl

REST and SOAP API

Components of Web GIS-

Mapping Applications

ESRI WebADF/JavaScript API Google Maps API /ArcGIS JS Extension Google Earth API Bing Maps API /ArcGIS JS Extension Bing Maps Silverlight API (Microsoft) Flex (Adobe) / ArcGIS Extension Yahoo Maps API OpenLayers API ArcGIS for iPhone API coming soon.

Examples of extensible Mapping Applications:

A mapping application is a web component/page that handles requests/responses to and from the mapping server.

Typical functionality includes handling navigation panning/zooming, layer management, attribute queries and advanced processing tasks (buffer, distance calculations, etc).

Components of Web GIS- JavaScript Class Libraries

JavaScript class libraries are an optional piece of a web GIS stack that can add some dynamic user interface components such as sliders, pop-up boxes, dynamic table grids, and AJAX (Asynchronous JavaScript and XML) handling.

Some popular JavaScript class libraries to consider are:

Dojo

EXT.JS

YUI (Yahoo User Interface)

jQuery

Can get from http://code.google.com/apis/ajaxlibs/

What is a mashup?

a mashup is a web page or application that combines data or functionality from two or more external sources to create a new service.

The term mashup implies easy, fast integration, frequently using open APIs and data sources to produce results that were not the original reason for producing the raw source data.

Source: Wikipedia.

A simple web mapping application

Basic HTML and JavaScript will get you a long ways.

ESRI Resource Center

http://resources.esri.com/arcgisserver/index.cfm?fa=home

Examples of Mapping Mash-ups

Measure 37 Viewer ORWAP Oregon Restoration

Measure 37 Viewerhttp://oeapp.oregonexplorer.info/M37Viewer

• Virtual Earth/Bing Maps- JavaScript API• Overlay WMS from ArcIMS

– Transparency slider, legend• Create active objects (pushpins, polygons).

– Uses GET_FEATURES call to ArcIMS to draw polygons.

• 3D Functionality.

ORWAP- Oregon Rapid Wetland Assessment Protocol http://oregonexplorer.info/wetlands/ORWAP/

Uses ArcGIS server map and geometry services.

Buffers selected point and queries intersection of layers.

Uses Virtual Earth/Bing JavaScript Extension for ArcGIS server.

Oregon Watershed Restoration Tool

1. ArcGIS Server 9.3 mapping backend2. Bing GeoRSS Collections for basin, subbasin and watershed council

layers.3. REST and SOAP used for getting layer data and overlaying WMS.4. DOJO javascript class library for more interactive user interface.