CheckExtension (arcpy)

Summary

Checks to see if a license is available to be checked out for a specific type of extension.

Once the extension license has been retrieved by the script, tools using that extension can be used. Once a script is finished with an extension's tools, the CheckInExtension function should be used to return the license to the License Manager so other applications can use it. All checked-out extension licenses and set product licenses are returned to the License Manager when a script completes.

Syntax

CheckExtension (extension_code)

Parameter	Explanation	Data Type
extension_code	Keyword for the extension product that is being checked. 3D —ArcGIS 3D Analyst extension Datareviewer —ArcGIS Data Reviewer for Desktop DataInteroperability —ArcGIS Data Interoperability extension for Desktop Airports —ArcGIS for Aviation: Airports Aeronautical —ArcGIS for Aviation: Charting Bathymetry —ArcGIS for Maritime: Bathymetry Nautical —ArcGIS for Maritime: Charting GeoStats —ArcGIS Geostatistical Analyst extension Network —ArcGIS Network Analyst extension Spatial —ArcGIS Spatial Analyst extension Schematics —ArcGIS Schematics extension Tracking —ArcGIS Tracking Analyst extension JTX —ArcGIS Workflow Manager for Desktop ArcScan —ArcScan Business —Business Analyst Defense —Esri Defense Solution Foundation —Esri Production Mapping Highways —Esri Roads and Highways StreetMap —StreetMap Licensing and extensions	String

Return Value

Data Type	Explanation
String	There are four possible returned values for CheckExtension: Available —The requested license is available to be set. Unavailable —The requested license is unavailable to be set. NotLicensed —The requested license is not valid. Failed —A system failure occurred during request.

Code Sample

CheckExtension example

Check for availability of 3D Analyst extension before checking it out.

import arcpy

class LicenseError(Exception):
    pass

try:
    if arcpy.CheckExtension("3D") == "Available":
        arcpy.CheckOutExtension("3D")
    else:
        # raise a custom exception
        raise LicenseError

    arcpy.env.workspace = "c:/GrosMorne"
    arcpy.HillShade_3d("WesternBrook", "wbrook_hill", 300)
    arcpy.Aspect_3d("WesternBrook", "wbrook_aspect")
    arcpy.CheckInExtension("3D")

except LicenseError:
    print("3D Analyst license is unavailable")
except arcpy.ExecuteError:
    print(arcpy.GetMessages(2))