torque/utils

torque.py

Description

The torque.py script lets you export Torque tilecubes to static files for storage and use. This script can be useful for storage and backup of your Torque visualizations as well as using the Torque library offline or where the CartoDB backend isn't needed.

Usage

Below are a list of parameters shared for both datasources (CartoDB and Postgis):

Option	Short	type	Description
--aggregation	-a	string	SQL aggregation function to calculate each pixel value
--ordering	-o	string	The name of the column (either number or date) that orders your data
--is_time	-q	string	Default True, set to false if your ordering column is not temporal
--steps	-s	integer	The number of ordered steps in your tile cubes
--resolution	-r	integer	The width and height dimensions of each pixel
--zoom	-z	string	The zoom extents to generate tiles
--dir	-d	string	Optional. The directory to store your output
--verbose	-v	none	Optional. Verbose log output

CartoDB data source

Example

python torque.py cartodb -u andrew -t all_week  -a 'count(*)' -o time 
-s 2 -r 4 -z 0-1  -d tiles -v

Options

Option	Short	type	Description
--user	-u	string	Name of the account where the tiles are generated
--table	-t	string	Name of the table where the Torque data is hosted
--api_key	-k	string	Optional. Your account api_key if the table is set to private

PostGIS data source

#####Example

python torque.py postgis -u andrew -t all_week  -a 'count(*)' -o time 
-s 2 -r 4 -z 0-1 -w "ST_Transform(the_geom, 3857)" --pg_host localhost 
--pg_db postgresql --pg_user postgresql -d tiles

Option	Short	type	Description
--pg_host		string	Hostname of your PostgreSQL database
--pg_db		string	PostgreSQL database name
--pg_user		string	PostgreSQL username
--webmercator	-w	string	Either a column containing your webmercator geometry or a quoted SQL statement to transform a geometry on the fly to webmercator.

Storage

A each Torque tile is a small JSON document that matches the dimensions of a map tile in webmercator. Just like web tiles, Torque tiles are stored in a nested folder structure that follows the organization {zoom level}/{x coordinate}/{y coordinate}.json.torque.