geocoder

Geocoder: City of Toronto

Geocoding is the act of taking an address and returning its coordinates, its longitude and latitude.

>> 299 Queen St W
Location: [-79.39038, 43.64955]

This geocoder supports both street addresses and intersections in the city of Toronto.

>> College St / Spadina Ave
Location: [-79.40005, 43.65795]

When programming, it's common to list longitude before latitude before as that matches the intuitive [x, y] construction for cartesian coordinates.

Why build this?

Most geocoding services available on the web are cost prohibitive for offline analysis of large datasets. For instance, Google's Geocoding API has a USD$4 CPM cost for requests at high volume.

For instance, a municipal open dataset like the City of Toronto's record of parking tickets would be very costly to geocode as it contains many records located at tens of thousands of addresses across the city from many prior years.

With this open source software, that work is free.

Building the index

The index is built live from real municipal open datasets each time the indexer is run.

The resulting index is saved on disk in recordIO format using this protocol buffer for serialization.

%> go run indexer/main.go
Indexing...

Ingesting Toronto addresses...
downloading 100% |██████████████████████████████████████████████████████| (571/571 MB, 12 MB/s)
525767 addresses written to file

Ingesting Toronto intersections,,,
downloading 100% |██████████████████████████████████████████████████████| (38/38 MB, 12 MB/s)
47416 intersections written to file

Wrote ./toronto_geocode.dat

Usage

First, start the service:

%> go run main.go
⠙ Loading geocoder index...  [27s] ready!
>> 

The geocoding service is available both on the command line and as a Go library. On the command line, simply enter your query and get a result:

>> 299 Queen St W
Location: [-79.39038, 43.64955]

Contributing

Some places to start:

• New municipalities (Missisauga, Markham, Pickering, etc).
• Points of Interest sourced from OSM.
• Command-line GRPC server/client for high-throughput scripting.