Map services
Map services |
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| Release 9.3 |
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A map service is the most common ArcGIS service and can contain many capabilities and functions. Map services certainly support mapping and map viewing, but can also support modeling and geoprocessing, mobile GIS services, and open publishing as OGC WMS, OGC WCS, and KML. For example, you can use a map service to deploy mobile GIS applications; geoprocessing tools to access geoprocessing services; or a geodata service that enables you to select an area of interest from a geodatabase, check out the data for editing, and subsequently post the edits back to the original geodatabase.
To create a map service, you first need to create the map document (.mxd) in ArcMap and publish it as a service. You can also serve published map files (.pmf) created using the optional ArcGIS Publisher extension to ArcGIS Desktop. The resulting map service provides access to the data, allowing you to display the layers in the map, and also utilize any functionality built into the map. Optionally, you can create a map cache and associate it with the service for faster map drawing.
You must use ArcGIS Desktop to create the map document. The ArcGIS Desktop Help contains many topics on using ArcMap to create map documents. A good starting place is An overview of ArcMap.
Creating a map for a service involves different considerations than preparing a printed map. Map service users generally cannot see all of the map at once and will need to pan and zoom to view their areas of interest.
All map services begin with a map document in ArcMap. Long before you publish your service, you should begin thinking about how you want to design your map so that it will perform acceptably and look appealing when published as a service.
The ArcGIS Desktop Help contains a book called Creating and publishing web maps that is designed to help you think about authoring map documents for ArcGIS Server. The book is written for ArcMap users who may be new to ArcGIS Server.
Also, see the next topic in this section Map authoring considerations for ArcGIS Server for specific tips.
You can consume map services with rotated data frames in .NET Web applications built with Manager or the Web Application Developer Framework (ADF). When you create a Web application in Manager, you specify which service's coordinate system and extent the map will use. This service, the Primary Map Resource, also determines the rotation of the map.
When using map services with rotated data frames, if your Primary Map Resource is rotated, you cannot use nonrotatable service types, such as ArcIMS and WMS, in the same map. If you set the nonrotatable service as the Primary Map Resource, the Web ADF will unrotate your rotated service on the fly so that it lines up with the nonrotatable service.
Note: Maps with rotated data frames cannot be cached. Also, you should not set EnableTileCaching = True on a Map control containing a map service with a rotated data frame.
To make the map document available as a service, follow the steps in Publishing a GIS resource to the server. When prompted to choose a resource, browse to the map document you created.
When you publish a map service, you have the option to enable capabilities that create additional services that work from or with the map service. Some capabilities require that your map document contain specific types of layers.
This table lists the capabilities that are available with map services and any special requirements for enabling the capability. This help system contains topics on each of the service types created by these capabilities, which you can access by clicking the capability name below:
| Capability | What it does | Special requirements? |
| Mapping | Provides access to the contents of a map document. | This capability is always enabled for any map document. |
| WCS | Uses the raster layers in the map document to create a service compliant with the Open Geospatial Consortium's (OGC) Web Coverage Service (WCS) specification. | Requires raster layers. |
| WFS | Uses the layers in a map document to create a service compliant with the Open Geospatial Consortium's (OGC) Web Feature Service (WFS) specification. | Requires vector layers. Raster layers are not included in the service, since the purpose of WFS is to serve vector feature geometry. |
| WMS | Uses a map document to create a service compliant with the Open Geospatial Consortium's (OGC) Web Map Service (WMS) specification. | None |
| Mobile Data Access | Allows extraction of data from a map document to a mobile device. | None |
| KML | Uses a map document to create Keyhole Markup Language (KML) features. | None |
| Geodata Access | Allows an end user to perform replication and data extraction in ArcMap. | Requires a layer from a geodatabase. Creates a geodata service that works with the map service. |
| Geoprocessing | Provides access to geoprocessing models from a tool layer. A tool layer represents a model that has been dragged from ArcToolbox into a map document's table of contents. | Requires a tool layer. Creates a geoprocessing service that works with the map service. |
| Network Analysis | Solves transportation network analysis problems using the Network Analyst extension. | Requires a network analysis layer referencing a network dataset. |
A map cache is a collection of prerendered map tiles that can be used for display of a map service. As mentioned above, cached services display quickly because the map image does not have to be rendered on the fly; the cost of rendering the image is paid only once when the cache is created.
The map service needs to be created and started before you can create the cache. You can access the cache generation tools through the Service Properties page in ArcCatalog. For detailed instructions see Creating cache tiles.
Once you've created the map service, it will be available to both local and Internet clients of the GIS server. Because of the many capabilities it exposes, a map service can be used in a large number of ESRI and non-ESRI applications. These include the following:
Following are notes on using map services in some of the most common ESRI client applications.
When you build a Web Mapping Application using ArcGIS Server Manager, you specify which map services you want to appear in the map display. The services are displayed in the application using the Web ADF Map control. You can also use the Map control to build an application from scratch.
The Map control supports navigation shortcuts, such as panning and scroll wheel zooming, and can also be buddied to a Toolbar control to support map query and advanced navigation. If you don't want or need the Map control, you can still connect to and work with a map service programmatically using the libraries included with ArcGIS Server and the Web ADF. For more information, see the ArcGIS Server Developer Help.
You can obtain ArcGIS Explorer for free from the ESRI Web site or with the ArcGIS Server product and use it as a client for your ArcGIS Server services. ArcGIS Server map services can be added to both two and three-dimensional maps in ArcGIS Explorer.
Both ArcMap and ArcGlobe support adding ArcGIS Server map services as data. Additionally, you can use ArcCatalog to preview and administer a map service.
If you are accessing a Web-enabled map service using ArcGIS Desktop, the Binary messaging format must be enabled for the service. Messaging formats are set at the root folder level, so to change the messaging format for a service, you must use ArcCatalog or Manager to edit to the root folder's properties. By default, both Binary and SOAP messaging formats are enabled.