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Example Search plug-in Python code sample

The ExampleSearch search plug-in for GEE Server provides the interface to query a SQL database of San Francisco neighborhoods via a search tab in Google Earth EC or a browser. The following description captures the overall mechanism of the plug-in but we recommend that you take a look at the code directly.

You can find the two Python files for the ExampleSearch plug-in in the following location:



In Google Earth Enterprise, a search plug-in Python-based framework relies on the Python Web Server Gateway Interface (WSGI), a Python API that acts as an interface between web servers and web applications. The web application or framework, search plug-in, is represented to the server as a Python callable method, __call__ to start the application. The callable method must include two arguments:

A request returns a response_body, the search results that are sent back to the requesting client wrapped in a list.

The handler,, is the actual plug-in code. It defines a class, ExampleSearch, which demonstrates how to construct and query a spatial database based on a URL search string, extract geometries from the result, associate various styles with them and return the response back to the client. The query definition, RunExampleSearch, performs a query search on the san_francisco_neighborhoods SQL table, with a response type of KML for Google Earth EC, or JSONP for a browser client, and returning the results as a list.

JSON object and response structure

The JSON object defined in, and the JSON response returned from the query, follow the default map structure that is bundled with GEE. If you want to create your own map application using a custom search response, you can structure the JSON to take advantage of Google Maps Javascript API functionality.

For example, if you have GeoJSON data, a standard for geospatial data on the internet, the google.maps.Data class allows you to add GeoJSON data to your map. The Data class follows the structure of GeoJSON in its data representation and makes it easy to import GeoJSON data and display points, line-strings and polygons. For more information about the Data Layer of Google Maps Javascript API, see

SQL query settings

The query that runs is hard-coded to the database scheme of the san_francisco_neighborhoods SQL table so if you have different schema, you’ll need to change the query. The search query is standard SQL available at: /opt/google/gehttpd/wsgi-bin/search/common/ For example, the following snippet shows the SQL query used to return the polygon perimeters of the neighborhoods listed in the “san_francisco_neighborhoods” SQL table:

self.example_query = ( "SELECT ${FUNC}(ST_Force_3DZ(the_geom)) AS the_geom,Area(the_geom)," "Perimeter(the_geom),sfar_distr,nbrhood, " "GeometryType(the_geom) AS geom_type " "FROM san_francisco_neighborhoods " "WHERE " "lower(nbrhood) like %s" )

As the /opt/google/gehttpd/wsgi-bin/search/common/ file includes the queries for all the system search plug-ins provided with Google Earth Enterprise, you can check out the various constructs to help you build your plug-in. We recommend that you keep your SQL query in the handler of your plug-in.

KML Geometric types supported

The ExampleSearch plug-in returns polygons, but all KML geometric types are supported.

Only point type query results will fly to first element; with geometric types, the query result flies to a bounding box within which all search results are visible.