--- /dev/null
+#!/usr/bin/env python3
+
+# © Copyright 2022, Scott Gasch
+
+"""Wrapper around US Census address geocoder API described here:
+
+* https://www2.census.gov/geo/pdfs/maps-data/data/Census_Geocoder_User_Guide.pdf
+* https://geocoding.geo.census.gov/geocoder/Geocoding_Services_API.pdf
+
+Also try::
+
+ --form benchmark=2020 \
+ https://geocoding.geo.census.gov/geocoder/locations/addressbatch \
+ --output geocoderesult.csv
+"""
+
+import functools
+import json
+import logging
+from typing import Any, Dict, List, Optional
+
+import requests
+from requests.utils import requote_uri
+
+from pyutils import list_utils
+
+logger = logging.getLogger(__name__)
+
+
+def geocode_address(address: str) -> Optional[Dict[str, Any]]:
+ """Send a single address to the US Census geocoding API in order to
+ lookup relevant data about it (including, if possible, its
+ lat/long). The response is a parsed JSON chunk of data with N
+ addressMatches in the result section and the details of each match
+ within it.
+
+ Args:
+ address: the full address to lookup in the form: "STREET
+ ADDRESS, CITY, STATE, ZIPCODE". These components may be
+ omitted and the service will make educated guesses but
+ the commas delimiting each component must be included.
+
+ Returns:
+ A parsed json dict with a bunch of information about the
+ address contained within it. Each 'addressMatch'
+ in the JSON describes the details of a possible match.
+ Returns None if there was an error or the address is
+ not known.
+
+ >>> json = geocode_address('4600 Silver Hill Rd,, 20233')
+ >>> json['result']['addressMatches'][0]['matchedAddress']
+ '4600 SILVER HILL RD, WASHINGTON, DC, 20233'
+
+ >>> json['result']['addressMatches'][0]['coordinates']
+ {'x': -76.9274328556918, 'y': 38.845989080537514}
+ """
+ url = "https://geocoding.geo.census.gov/geocoder/geographies/onelineaddress"
+ url += f"?address={address}"
+ url += "&returntype=geographies&layers=all&benchmark=4&vintage=4&format=json"
+ url = requote_uri(url)
+ logger.debug("GET: %s", url)
+ try:
+ r = requests.get(url, timeout=10.0)
+ except Exception as e:
+ logger.exception(e)
+ return None
+
+ if not r.ok:
+ logger.debug(r.text)
+ logger.error("Unexpected response code %d, wanted 200. Fail.", r.status_code)
+ return None
+ logger.debug("Response: %s", json.dumps(r.json(), indent=4, sort_keys=True))
+ return r.json()
+
+
+def batch_geocode_addresses(addresses: List[str]) -> Optional[List[str]]:
+ """Send a list of addresses for batch geocoding to a web service
+ operated by the US Census Bureau.
+
+ Args:
+ addresses: a list of addresses to geocode. Each line of the
+ input list should be a single address in the form: "STREET
+ ADDRESS, CITY, STATE, ZIPCODE". Individual address components
+ may be omitted and the service will make educated guesses but
+ the commas delimiters between address components may not be
+ omitted.
+
+ Returns:
+ An array of the same size as the input array with one
+ answer record per line. Returns None on error.
+
+ Note: this code will deal with requests >10k addresses by chunking
+ them internally because the census website disallows requests >
+ 10k lines.
+
+ >>> batch_geocode_addresses(
+ ... [
+ ... '4600 Silver Hill Rd, Washington, DC, 20233',
+ ... '935 Pennsylvania Avenue, NW, Washington, DC, 20535-0001',
+ ... '1600 Pennsylvania Avenue NW, Washington, DC, 20500',
+ ... '700 Pennsylvania Avenue NW, Washington, DC, 20408',
+ ... ]
+ ... )
+ ['"1"," 4600 Silver Hill Rd, Washington, DC, 20233","Match","Exact","4600 SILVER HILL RD, WASHINGTON, DC, 20233","-76.92743285599994,38.84598908100003","76355984","L","24","033","802405","2004"', '"2"," 935 Pennsylvania Avenue, NW, Washington, DC","No_Match"', '"3"," 1600 Pennsylvania Avenue NW, Washington, DC, 20500","Match","Exact","1600 PENNSYLVANIA AVE NW, WASHINGTON, DC, 20500","-77.03654072899997,38.89874352700008","76225813","L","11","001","980000","1034"', '"4"," 700 Pennsylvania Avenue NW, Washington, DC, 20408","Match","Exact","700 PENNSYLVANIA AVE NW, WASHINGTON, DC, 20408","-77.02304089899997,38.89361872300003","76226346","L","11","001","980000","1025"']
+ """
+
+ n = 1
+ url = "https://geocoding.geo.census.gov/geocoder/geographies/addressbatch"
+ payload = {"benchmark": "4", "vintage": "4"}
+ out = []
+ for chunk in list_utils.shard(addresses, 9999):
+ raw_file = ""
+ for address in chunk:
+ raw_file += f"{n}, {address}\n"
+ n += 1
+ files = {"addressFile": ("input.csv", raw_file)}
+ logger.debug("POST: %s", url)
+ try:
+ r = requests.post(url, files=files, data=payload, timeout=10.0)
+ except Exception as e:
+ logger.exception(e)
+ return None
+
+ if not r.ok:
+ logger.debug(r.text)
+ logger.error(
+ "Unexpected response code %d, wanted 200. Fail.", r.status_code
+ )
+ return None
+ logger.debug("Response: %s", r.text)
+ for line in r.text.split("\n"):
+ line = line.strip()
+ if len(line) > 0:
+ out.append(line)
+ return out
+
+
+if __name__ == "__main__":
+ import doctest
+
+ doctest.testmod()