#!/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://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 json
import logging
-import re
-from typing import Dict, Optional
+from typing import Any, Dict, List, Optional
import requests
-from bs4 import BeautifulSoup
-from requests.utils import quote
+from requests.utils import requote_uri
+
+import list_utils
logger = logging.getLogger(__name__)
-def geocode_address(address: str) -> Optional[Dict[str, str]]:
- """Send a single address to the US Census geocoding API.
+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.
- >>> out = geocode_address('5 Shelbern Dr,,, 07738')
- >>> out['Matched Address']
- '5 SHELBERN DR, LINCROFT, NJ, 07738'
+ 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}
"""
- encoded_address = quote(address)
url = 'https://geocoding.geo.census.gov/geocoder/geographies/onelineaddress'
- url += f'?address={encoded_address}'
- url += '&layers=all&benchmark=4&vintage=4'
+ url += f'?address={address}'
+ url += '&returntype=geographies&layers=all&benchmark=4&vintage=4&format=json'
+ url = requote_uri(url)
logger.debug('GET: %s', url)
- r = requests.get(url)
+ try:
+ r = requests.get(url)
+ except Exception as e:
+ logger.exception(e)
+ return None
+
if r.status_code != 200:
- logger.error(f'Unexpected response code {r.status_code}, wanted 200. Fail.')
+ logger.debug(r.text)
+ logger.error('Unexpected response code %d, wanted 200. Fail.', r.status_code)
return None
- else:
- soup = BeautifulSoup(r.text, 'html.parser')
- result = soup.find('div', id='pl_gov_census_geo_geocoder_domain_AddressResult')
- logger.debug('Unhelpful result blurb: "%s"', result)
- output = result.get_text('\n')
- label = None
- out = {}
- for line in output.split('\n'):
- if re.match(r'.*: *$', line):
- label = line[:-2].strip()
- logger.debug('Label is: "%s"', label)
- else:
- if label:
- out[label] = line.strip()
- logger.debug('Value is: "%s"', out[label])
+ 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","-77.03534009999998,38.89875363300007","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)
+ except Exception as e:
+ logger.exception(e)
+ return None
+
+ if r.status_code != 200:
+ 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