In one of my SotM 2011 talks, I suggested that OSM
should have regular extracts of metropolitan areas for major world cities and
their surrounding areas, regardless of state or country. This is a repository
for a bit of code to make that real. I’ve decided to use Amazon S3 to host files,
and EC2 to do the extracting. extract.sh is a script that performs the
actual work with Osmosis and
terminates its host machine upon completion.
Extractotron is run a few times per month, to http://metro.teczno.com. If you have cities to add, you can add them directly to cities.txt and send me a pull request in Github.
cities.txt is a tab-delimited file, and has eight fields:
-
group
One of "Africa", "Asia", "Europe", "Middle East", "North America", "South America", or Oceania.
-
geonameid
It's nice to have a link back to the Geonames dataset.
-
top, left, bottom, right
Geographic bounding box of the metropolitan area. These should be larger rather than smaller to surrounding countryside wherever possible. For example of coverage area, see Moscow.
-
slug
Short, lowercase version of the name with dashes for spaces that's used for files.
-
name
Full name of the city.
To use Extractotron yourself, use run-instance.py:
python run-instance.py <your AWS access key> <your AWS secret> <your bucket name>
By default, run-instance.py instantiates an m1.large instance with Alestic's
Ubuntu 11.04 Natty instance-store AMI ami-68ad5201. You can change the instance
type or AMI, see python run-instance.py --help for details.
Currently, the cities list is very short. Help me expand it by modifying
cities.txt and sending a pull request via Github.