X-Git-Url: https://git.openstreetmap.org./nominatim.git/blobdiff_plain/8b1a509442a3fa051146f82b8293126916ad8617..754846d9dc125e3caa8a97b8381918b565a55289:/nominatim/tools/postcodes.py diff --git a/nominatim/tools/postcodes.py b/nominatim/tools/postcodes.py index 78bd8cb9..d00fc97a 100644 --- a/nominatim/tools/postcodes.py +++ b/nominatim/tools/postcodes.py @@ -2,80 +2,206 @@ 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.utils import execute_file from nominatim.db.connection import connect -def import_postcodes(dsn, project_dir, tokenizer): - """ Set up the initial list of postcodes. +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() - with connect(dsn) as conn: - conn.drop_table('gb_postcode') - conn.drop_table('us_postcode') + 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: - cur.execute("""CREATE TABLE gb_postcode ( - id integer, - postcode character varying(9), - geometry GEOMETRY(Point, 4326))""") + 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("""CREATE TABLE us_postcode ( - postcode text, - x double precision, - y double precision)""") - conn.commit() + 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) - gb_postcodes = project_dir / 'gb_postcode_data.sql.gz' - if gb_postcodes.is_file(): - execute_file(dsn, gb_postcodes) + to_add = [(k, v[0], v[1]) for k, v in self.collected.items()] + self.collected = [] - us_postcodes = project_dir / 'us_postcode_data.sql.gz' - if us_postcodes.is_file(): - execute_file(dsn, us_postcodes) + return to_add, to_delete, to_update - with conn.cursor() as cur: - cur.execute("TRUNCATE location_postcode") - cur.execute(""" - INSERT INTO location_postcode - (place_id, indexed_status, country_code, postcode, geometry) - SELECT nextval('seq_place'), 1, country_code, - token_normalized_postcode(address->'postcode') as pc, - ST_Centroid(ST_Collect(ST_Centroid(geometry))) - FROM placex - WHERE address ? 'postcode' - and token_normalized_postcode(address->'postcode') is not null - AND geometry IS NOT null - GROUP BY country_code, pc - """) - - cur.execute(""" - INSERT INTO location_postcode - (place_id, indexed_status, country_code, postcode, geometry) - SELECT nextval('seq_place'), 1, 'us', - token_normalized_postcode(postcode), - ST_SetSRID(ST_Point(x,y),4326) - FROM us_postcode WHERE token_normalized_postcode(postcode) NOT IN - (SELECT postcode FROM location_postcode - WHERE country_code = 'us') - """) - - cur.execute(""" - INSERT INTO location_postcode - (place_id, indexed_status, country_code, postcode, geometry) - SELECT nextval('seq_place'), 1, 'gb', - token_normalized_postcode(postcode), geometry - FROM gb_postcode WHERE token_normalized_postcode(postcode) NOT IN - (SELECT postcode FROM location_postcode - WHERE country_code = 'gb') - """) - - cur.execute(""" - DELETE FROM word WHERE class='place' and type='postcode' - and word NOT IN (SELECT postcode FROM location_postcode) - """) - conn.commit() - - with tokenizer.name_analyzer() as analyzer: - analyzer.add_postcodes_from_db() + + 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')