mirror of
https://github.com/osm-search/Nominatim.git
synced 2024-12-28 23:42:59 +03:00
208 lines
8.1 KiB
Python
208 lines
8.1 KiB
Python
"""
|
|
Functions for importing, updating and otherwise maintaining the table
|
|
of artificial postcode centroids.
|
|
"""
|
|
import csv
|
|
import gzip
|
|
import logging
|
|
from math import isfinite
|
|
|
|
from psycopg2 import sql as pysql
|
|
|
|
from nominatim.db.connection import connect
|
|
|
|
LOG = logging.getLogger()
|
|
|
|
def _to_float(num, max_value):
|
|
""" Convert the number in string into a float. The number is expected
|
|
to be in the range of [-max_value, max_value]. Otherwise rises a
|
|
ValueError.
|
|
"""
|
|
num = float(num)
|
|
if not isfinite(num) or num <= -max_value or num >= max_value:
|
|
raise ValueError()
|
|
|
|
return num
|
|
|
|
class _CountryPostcodesCollector:
|
|
""" Collector for postcodes of a single country.
|
|
"""
|
|
|
|
def __init__(self, country):
|
|
self.country = country
|
|
self.collected = dict()
|
|
|
|
|
|
def add(self, postcode, x, y):
|
|
""" Add the given postcode to the collection cache. If the postcode
|
|
already existed, it is overwritten with the new centroid.
|
|
"""
|
|
self.collected[postcode] = (x, y)
|
|
|
|
|
|
def commit(self, conn, analyzer, project_dir):
|
|
""" Update postcodes for the country from the postcodes selected so far
|
|
as well as any externally supplied postcodes.
|
|
"""
|
|
self._update_from_external(analyzer, project_dir)
|
|
to_add, to_delete, to_update = self._compute_changes(conn)
|
|
|
|
LOG.info("Processing country '%s' (%s added, %s deleted, %s updated).",
|
|
self.country, len(to_add), len(to_delete), len(to_update))
|
|
|
|
with conn.cursor() as cur:
|
|
if to_add:
|
|
cur.execute_values(
|
|
"""INSERT INTO location_postcode
|
|
(place_id, indexed_status, country_code,
|
|
postcode, geometry) VALUES %s""",
|
|
to_add,
|
|
template=pysql.SQL("""(nextval('seq_place'), 1, {},
|
|
%s, 'SRID=4326;POINT(%s %s)')
|
|
""").format(pysql.Literal(self.country)))
|
|
if to_delete:
|
|
cur.execute("""DELETE FROM location_postcode
|
|
WHERE country_code = %s and postcode = any(%s)
|
|
""", (self.country, to_delete))
|
|
if to_update:
|
|
cur.execute_values(
|
|
pysql.SQL("""UPDATE location_postcode
|
|
SET indexed_status = 2,
|
|
geometry = ST_SetSRID(ST_Point(v.x, v.y), 4326)
|
|
FROM (VALUES %s) AS v (pc, x, y)
|
|
WHERE country_code = {} and postcode = pc
|
|
""").format(pysql.Literal(self.country)), to_update)
|
|
|
|
|
|
def _compute_changes(self, conn):
|
|
""" Compute which postcodes from the collected postcodes have to be
|
|
added or modified and which from the location_postcode table
|
|
have to be deleted.
|
|
"""
|
|
to_update = []
|
|
to_delete = []
|
|
with conn.cursor() as cur:
|
|
cur.execute("""SELECT postcode, ST_X(geometry), ST_Y(geometry)
|
|
FROM location_postcode
|
|
WHERE country_code = %s""",
|
|
(self.country, ))
|
|
for postcode, x, y in cur:
|
|
newx, newy = self.collected.pop(postcode, (None, None))
|
|
if newx is not None:
|
|
dist = (x - newx)**2 + (y - newy)**2
|
|
if dist > 0.0000001:
|
|
to_update.append((postcode, newx, newy))
|
|
else:
|
|
to_delete.append(postcode)
|
|
|
|
to_add = [(k, v[0], v[1]) for k, v in self.collected.items()]
|
|
self.collected = []
|
|
|
|
return to_add, to_delete, to_update
|
|
|
|
|
|
def _update_from_external(self, analyzer, project_dir):
|
|
""" Look for an external postcode file for the active country in
|
|
the project directory and add missing postcodes when found.
|
|
"""
|
|
csvfile = self._open_external(project_dir)
|
|
if csvfile is None:
|
|
return
|
|
|
|
try:
|
|
reader = csv.DictReader(csvfile)
|
|
for row in reader:
|
|
if 'postcode' not in row or 'lat' not in row or 'lon' not in row:
|
|
LOG.warning("Bad format for external postcode file for country '%s'."
|
|
" Ignored.", self.country)
|
|
return
|
|
postcode = analyzer.normalize_postcode(row['postcode'])
|
|
if postcode not in self.collected:
|
|
try:
|
|
self.collected[postcode] = (_to_float(row['lon'], 180),
|
|
_to_float(row['lat'], 90))
|
|
except ValueError:
|
|
LOG.warning("Bad coordinates %s, %s in %s country postcode file.",
|
|
row['lat'], row['lon'], self.country)
|
|
|
|
finally:
|
|
csvfile.close()
|
|
|
|
|
|
def _open_external(self, project_dir):
|
|
fname = project_dir / '{}_postcodes.csv'.format(self.country)
|
|
|
|
if fname.is_file():
|
|
LOG.info("Using external postcode file '%s'.", fname)
|
|
return open(fname, 'r')
|
|
|
|
fname = project_dir / '{}_postcodes.csv.gz'.format(self.country)
|
|
|
|
if fname.is_file():
|
|
LOG.info("Using external postcode file '%s'.", fname)
|
|
return gzip.open(fname, 'rt')
|
|
|
|
return None
|
|
|
|
|
|
def update_postcodes(dsn, project_dir, tokenizer):
|
|
""" Update the table of artificial postcodes.
|
|
|
|
Computes artificial postcode centroids from the placex table,
|
|
potentially enhances it with external data and then updates the
|
|
postcodes in the table 'location_postcode'.
|
|
"""
|
|
with tokenizer.name_analyzer() as analyzer:
|
|
with connect(dsn) as conn:
|
|
# First get the list of countries that currently have postcodes.
|
|
# (Doing this before starting to insert, so it is fast on import.)
|
|
with conn.cursor() as cur:
|
|
cur.execute("SELECT DISTINCT country_code FROM location_postcode")
|
|
todo_countries = set((row[0] for row in cur))
|
|
|
|
# Recompute the list of valid postcodes from placex.
|
|
with conn.cursor(name="placex_postcodes") as cur:
|
|
cur.execute("""
|
|
SELECT cc as country_code, pc, ST_X(centroid), ST_Y(centroid)
|
|
FROM (SELECT
|
|
COALESCE(plx.country_code,
|
|
get_country_code(ST_Centroid(pl.geometry))) as cc,
|
|
token_normalized_postcode(pl.address->'postcode') as pc,
|
|
ST_Centroid(ST_Collect(COALESCE(plx.centroid,
|
|
ST_Centroid(pl.geometry)))) as centroid
|
|
FROM place AS pl LEFT OUTER JOIN placex AS plx
|
|
ON pl.osm_id = plx.osm_id AND pl.osm_type = plx.osm_type
|
|
WHERE pl.address ? 'postcode' AND pl.geometry IS NOT null
|
|
GROUP BY cc, pc) xx
|
|
WHERE pc IS NOT null AND cc IS NOT null
|
|
ORDER BY country_code, pc""")
|
|
|
|
collector = None
|
|
|
|
for country, postcode, x, y in cur:
|
|
if collector is None or country != collector.country:
|
|
if collector is not None:
|
|
collector.commit(conn, analyzer, project_dir)
|
|
collector = _CountryPostcodesCollector(country)
|
|
todo_countries.discard(country)
|
|
collector.add(postcode, x, y)
|
|
|
|
if collector is not None:
|
|
collector.commit(conn, analyzer, project_dir)
|
|
|
|
# Now handle any countries that are only in the postcode table.
|
|
for country in todo_countries:
|
|
_CountryPostcodesCollector(country).commit(conn, analyzer, project_dir)
|
|
|
|
conn.commit()
|
|
|
|
analyzer.update_postcodes_from_db()
|
|
|
|
def can_compute(dsn):
|
|
"""
|
|
Check that the place table exists so that
|
|
postcodes can be computed.
|
|
"""
|
|
with connect(dsn) as conn:
|
|
return conn.table_exists('place')
|