In part 1 of this two-part Maptime we focused on installing a number of back end tools that are indispensable for open source geo work: PostgreSQL, PostGIS, Python, and the osm2pgsql script. We looked at some simple queries, the Data Science Toolkit's geocoder, and strategies for acquiring OpenStreetMap data, particularly through the metro excerpts. Most of that work is reviewed in the first 20 or so slides in a still-evolving slide deck. If you didn't attend last week, or even if you did, you should review those slides.
In part 2, we'll hook MapBox's TileMill application up to our OSM database, explore the display layers and shapefiles, and tweak some CartoCSS in order to generate map tiles we'll serve from our own laptops. This will be immensely satisfying after all the grunt work of last week!
We'll also import additional geocoded data, and use Leaflet to lay that data over our tiles. We'll set up a simple web app to deliver that data in GeoJSON format, and, time permitting, we'll look at examples of Leaflet plugins and the power of spatial queries.
I have a few additional download instructions for tonight. As before, they require little attention, but they do take some time. Getting the shapefiles may take 30-40 minutes.
1. If you've never opened TileMill on your computer before, open it, then simply quit. That'll create the file structure you need for the next part.
2. Open your Terminal program and type
git clone [masked]:erictheise/sfbay_from_osm_deluxe.git
If you're missing git, you can
brew install git
Looking forward to seeing you all tonight.