Using the Google geocoding API to clean up some user-entered geographic locations of university names and then placing the data on a Google Map.
In this project, I am using the Google geocoding API to clean up some user-entered geographic locations of university names and then placing the data on a Google Map.
The first problem to solve is that the Google geocoding API is rate limited to a fixed number of requests per day. So we break the problem into two phases.
In the first phase we take our input data in the file
(where.data and read it one line at a time, and retrieve the
geocoded response and store it in a database geodata.sqlite.
Before we use the geocoding API, we simply check to see if
we already have the data for that particular line of input.
You can re-start the process at any time by removing the file
geodata.sqlite
Run the geoload.py program.
This program will read the input
lines in where.data and for each line check to see if it is already
in the database and if we don't have the data for the location,
call the geocoding API to retrieve the data and store it in
the database.
The Google Geocoding APIs moved some functionality that we use from the Geocoding API into the Places API. Also all the Google Geo-related APIs require an API key. To complete this without a Google account, without an API key, or from a country that blocks access to Google, you can use a subset of that data which is available at:
http://py4e-data.dr-chuck.net/json
To use this, simply leave the api_key set to False in geoload.py.
This URL only has a subset of the data but it has no rate limit so it is good for testing.
If you want to try this with the API key, follow the instructions at:
https://developers.google.com/maps/documentation/geocoding/intro
and put the API key in the code.
Once you have some data loaded into geodata.sqlite, you can
visualize the data using the geodump.py program. This
program reads the database and writes tile file where.js
with the location, latitude, and longitude in the form of
executable JavaScript code.
The file where.html consists of HTML and JavaScript to visualize
a Google Map. It reads the most recent data in where.js to get
the data to be visualized.
Simply open where.html in a browser to see the locations. You
can hover over each map pin to find the location that the
geocoding API returned for the user-entered input. If you
cannot see any data when you open the where.html file, you might
want to check the JavaScript or developer console for your browser.