+
+
+class SqliteWriter:
+ """ Worker class which creates a new SQLite database.
+ """
+
+ def __init__(self, src: napi.SearchConnection,
+ dest: napi.SearchConnection, options: Set[str]) -> None:
+ self.src = src
+ self.dest = dest
+ self.options = options
+
+
+ async def write(self) -> None:
+ """ Create the database structure and copy the data from
+ the source database to the destination.
+ """
+ LOG.warning('Setting up spatialite')
+ await self.dest.execute(sa.select(sa.func.InitSpatialMetaData(True, 'WGS84')))
+
+ await self.create_tables()
+ await self.copy_data()
+ if 'search' in self.options:
+ await self.create_word_table()
+ await self.create_indexes()
+
+
+ async def create_tables(self) -> None:
+ """ Set up the database tables.
+ """
+ LOG.warning('Setting up tables')
+ if 'search' not in self.options:
+ self.dest.t.meta.remove(self.dest.t.search_name)
+ else:
+ await self.create_class_tables()
+
+ await self.dest.connection.run_sync(self.dest.t.meta.create_all)
+
+ # Convert all Geometry columns to Spatialite geometries
+ for table in self.dest.t.meta.sorted_tables:
+ for col in table.c:
+ if isinstance(col.type, Geometry):
+ await self.dest.execute(sa.select(
+ sa.func.RecoverGeometryColumn(table.name, col.name, 4326,
+ col.type.subtype.upper(), 'XY')))
+
+
+ async def create_class_tables(self) -> None:
+ """ Set up the table that serve class/type-specific geometries.
+ """
+ sql = sa.text("""SELECT tablename FROM pg_tables
+ WHERE tablename LIKE 'place_classtype_%'""")
+ for res in await self.src.execute(sql):
+ for db in (self.src, self.dest):
+ sa.Table(res[0], db.t.meta,
+ sa.Column('place_id', sa.BigInteger),
+ sa.Column('centroid', Geometry))
+
+
+ async def create_word_table(self) -> None:
+ """ Create the word table.
+ This table needs the property information to determine the
+ correct format. Therefore needs to be done after all other
+ data has been copied.
+ """
+ await make_query_analyzer(self.src)
+ await make_query_analyzer(self.dest)
+ src = self.src.t.meta.tables['word']
+ dest = self.dest.t.meta.tables['word']
+
+ await self.dest.connection.run_sync(dest.create)
+
+ LOG.warning("Copying word table")
+ async_result = await self.src.connection.stream(sa.select(src))
+
+ async for partition in async_result.partitions(10000):
+ data = [{k: getattr(r, k) for k in r._fields} for r in partition]
+ await self.dest.execute(dest.insert(), data)
+
+ await self.dest.connection.run_sync(sa.Index('idx_word_woken', dest.c.word_token).create)
+
+
+ async def copy_data(self) -> None:
+ """ Copy data for all registered tables.
+ """
+ def _getfield(row: SaRow, key: str) -> Any:
+ value = getattr(row, key)
+ if isinstance(value, dt.datetime):
+ if value.tzinfo is not None:
+ value = value.astimezone(dt.timezone.utc)
+ return value
+
+ for table in self.dest.t.meta.sorted_tables:
+ LOG.warning("Copying '%s'", table.name)
+ async_result = await self.src.connection.stream(self.select_from(table.name))
+
+ async for partition in async_result.partitions(10000):
+ data = [{('class_' if k == 'class' else k): _getfield(r, k)
+ for k in r._fields}
+ for r in partition]
+ await self.dest.execute(table.insert(), data)
+
+ # Set up a minimal copy of pg_tables used to look up the class tables later.
+ pg_tables = sa.Table('pg_tables', self.dest.t.meta,
+ sa.Column('schemaname', sa.Text, default='public'),
+ sa.Column('tablename', sa.Text))
+ await self.dest.connection.run_sync(pg_tables.create)
+ data = [{'tablename': t} for t in self.dest.t.meta.tables]
+ await self.dest.execute(pg_tables.insert().values(data))
+
+
+ async def create_indexes(self) -> None:
+ """ Add indexes necessary for the frontend.
+ """
+ # reverse place node lookup needs an extra table to simulate a
+ # partial index with adaptive buffering.
+ await self.dest.execute(sa.text(
+ """ CREATE TABLE placex_place_node_areas AS
+ SELECT place_id, ST_Expand(geometry,
+ 14.0 * exp(-0.2 * rank_search) - 0.03) as geometry
+ FROM placex
+ WHERE rank_address between 5 and 25
+ and osm_type = 'N'
+ and linked_place_id is NULL """))
+ await self.dest.execute(sa.select(
+ sa.func.RecoverGeometryColumn('placex_place_node_areas', 'geometry',
+ 4326, 'GEOMETRY', 'XY')))
+ await self.dest.execute(sa.select(sa.func.CreateSpatialIndex(
+ 'placex_place_node_areas', 'geometry')))
+
+ # Remaining indexes.
+ await self.create_spatial_index('country_grid', 'geometry')
+ await self.create_spatial_index('placex', 'geometry')
+ await self.create_spatial_index('osmline', 'linegeo')
+ await self.create_spatial_index('tiger', 'linegeo')
+ await self.create_index('placex', 'place_id')
+ await self.create_index('placex', 'parent_place_id')
+ await self.create_index('placex', 'rank_address')
+ await self.create_index('addressline', 'place_id')
+ await self.create_index('postcode', 'place_id')
+ await self.create_index('osmline', 'place_id')
+ await self.create_index('tiger', 'place_id')
+
+ if 'search' in self.options:
+ await self.create_spatial_index('postcode', 'geometry')
+ await self.create_spatial_index('search_name', 'centroid')
+ await self.create_index('search_name', 'place_id')
+ await self.create_index('osmline', 'parent_place_id')
+ await self.create_index('tiger', 'parent_place_id')
+ await self.create_search_index()
+
+ for t in self.dest.t.meta.tables:
+ if t.startswith('place_classtype_'):
+ await self.dest.execute(sa.select(
+ sa.func.CreateSpatialIndex(t, 'centroid')))
+
+
+ async def create_spatial_index(self, table: str, column: str) -> None:
+ """ Create a spatial index on the given table and column.
+ """
+ await self.dest.execute(sa.select(
+ sa.func.CreateSpatialIndex(getattr(self.dest.t, table).name, column)))
+
+
+ async def create_index(self, table_name: str, column: str) -> None:
+ """ Create a simple index on the given table and column.
+ """
+ table = getattr(self.dest.t, table_name)
+ await self.dest.connection.run_sync(
+ sa.Index(f"idx_{table}_{column}", getattr(table.c, column)).create)
+
+
+ async def create_search_index(self) -> None:
+ """ Create the tables and indexes needed for word lookup.
+ """
+ LOG.warning("Creating reverse search table")
+ rsn = sa.Table('reverse_search_name', self.dest.t.meta,
+ sa.Column('word', sa.Integer()),
+ sa.Column('column', sa.Text()),
+ sa.Column('places', IntArray))
+ await self.dest.connection.run_sync(rsn.create)
+
+ tsrc = self.src.t.search_name
+ for column in ('name_vector', 'nameaddress_vector'):
+ sql = sa.select(sa.func.unnest(getattr(tsrc.c, column)).label('word'),
+ sa.func.ArrayAgg(tsrc.c.place_id).label('places'))\
+ .group_by('word')
+
+ async_result = await self.src.connection.stream(sql)
+ async for partition in async_result.partitions(100):
+ data = []
+ for row in partition:
+ row.places.sort()
+ data.append({'word': row.word,
+ 'column': column,
+ 'places': row.places})
+ await self.dest.execute(rsn.insert(), data)
+
+ await self.dest.connection.run_sync(
+ sa.Index('idx_reverse_search_name_word', rsn.c.word).create)
+
+
+ def select_from(self, table: str) -> SaSelect:
+ """ Create the SQL statement to select the source columns and rows.
+ """
+ columns = self.src.t.meta.tables[table].c
+
+ if table == 'placex':
+ # SQLite struggles with Geometries that are larger than 5MB,
+ # so simplify those.
+ return sa.select(*(c for c in columns if not isinstance(c.type, Geometry)),
+ sa.func.ST_AsText(columns.centroid).label('centroid'),
+ sa.func.ST_AsText(
+ sa.case((sa.func.ST_MemSize(columns.geometry) < 5000000,
+ columns.geometry),
+ else_=sa.func.ST_SimplifyPreserveTopology(
+ columns.geometry, 0.0001)
+ )).label('geometry'))
+
+ sql = sa.select(*(sa.func.ST_AsText(c).label(c.name)
+ if isinstance(c.type, Geometry) else c for c in columns))
+
+ return sql