GeocodeService

Geocoding REST service using GMaps and Here maps. Fetches the latitude/longitude given a street address.

Google Maps api is used as the primary geocoding provider by default. On failure or unavailability, Here maps is used. See below for details and configuration.

Requirements: Python 3 runtime. Tested against Python 3.6

Using the REST API

GET /geocode?address=xxx

Query parameter:

• address - the geographic address eg. 1600 Amphitheatre Parkway, Mountain View, CA

Response:

• response will be Content-type: application/json
• 400 HTTP code for invalid input
• 500 HTTP code for server error
• status is a code that indicates success or type of failure
  • OK - geocode found
  • INVALID - indicates invalid input
  • GEOCODE_NOT_FOUND - if no geocode was found
  • ERROR - server error occurred

Sample response:

{
    "status": "OK",
    "lat": 37.4216548,
    "lng": -122.0856374
}

Sample HTTP Get call: GET server:port/geocode?address=1600+Amphitheatre+Parkway,+Mountain+View,+CA

Run the service

Sample: python geocode_service.py --config config.ini --port 8081

Commandline usage:

usage: geocode_service.py [-h] [--config CONFIG] [--port PORT]

optional arguments:
  -h, --help       show this help message and exit
  --config CONFIG  config file to use; if omitted, defaults to config.ini. See
                   included sample for an example.
  --port PORT      server port to run service on; if omitted, defaults to
                   value in config file

Logging control:

• included logging.conf controls the logging configuration
• set the level property to set the logging level

Config file:

• Note: xxx values should be set to the appropriate value
• The Api keys below are required for the Google and Here services below
• The included config.ini file contains a running config with real API keys that can be used (within account limits).

Sample config file:

[DEFAULT]
ServerPort = 8081
RemoteTimeout = 3
PrimaryProvider = google
SecondaryProvider = here

[provider.google]
ApiKey = xxx

[provider.here]
AppId = xxx
AppCode = xxx

Extending the code

• 2 geocoding providers are provided: Google Maps, and Here Maps
• new Geocoding providers may be created via simply extending GeocodeProvider and setting them as the primary or secondary provider

TODOs/Future enhancements

• make the code follow the "Pythonic" way
• (future) use popular 3rd party libraries to handle a lot of the logic and simplify the code
• allow user to specify which geocode service to use in the API itself
• cache repeat, frequent queries
• secure storage of api keys
• allow list of fallback providers
• use enums to enumerate providers and validate
• return metadata in response (such as Geocode provider used)
• more thorough input validation (server port range check, config file, etc)
• more unit tests