FME Flow: 2024.2

KML Network Link Service

The KML Network Link service accepts and carries out transformation requests as specified by a workspace, returning the results as a KML Network Link that you can use with Google Earth.

Note   If you install this service, you must also install the Data Streaming service.

This service can be requested using a URL or form. For example,

http://<host>/fmekmllink/<repository>/<workspace>.fmw?<parameters>

The resulting response is a KMZ file that contains a KML Network Link. This link's URL points to the Data Streaming service and references the requested workspace. No translation is performed to provide the KMZ file. The results are always as up-to-date as the update interval in Google Earth.

Note  When Google Earth (or other application) is running and the KMZ file is loaded, the workspace that generated the file runs on a repeated basis until the application is closed. The default frequency is every 60 seconds. To change, update the REFRESH_INTERVAL directive in the KML Network Link properties file. This file is located in <FMEFlowDir>\Utilities\tomcat\webapps\fmekmllink\WEB-INF\conf\propertiesFile.properties.

Requirements

This service works with any workspace that writes KML and KMZ files. The following published parameters should exist in the workspace:

  • bboxEast: Bounding Box East
  • bboxWest: Bounding Box West
  • bboxNorth: Bounding Box North
  • bboxSouth: Bounding Box South

When the KML Network Link layer is enabled, Google Earth passes the extents of its current view window to these parameters. The coordinates are in lat-long. A workspace can use these parameters to read the source data with spatial queries.

Response Elements

If the KML Network Link service successfully processes the request, it returns a KML document enclosed in KMZ format to the client as a data stream. The KML document contains a NetworkLink element where Link/href is set to a URL. This URL invokes the FME Flow Data Streaming service with the provided repository and workspace name. For a complete reference of the KML format, refer to: https://developers.google.com/kml/documentation/

If the response format is specified as XML or JSON, a service failure response may contain the elements shown in the following table.

Element

Child Elements

Value

Description

statusInfo

message

message string

service failure message

status

success | failure

service status

See Also