Address points in buildings layer sometimes missing min_zoom

[nvkelso]

Occasionally the address points exported in the buildings layer are missing min_zoom props.

Besides the vanilla address nodes in OSM, Tilezen harvests address points in queries.yaml off ways as well via this transform.py logic:

• vector-datasource/vectordatasource/transform.py

  Lines 2505 to 2578 in 2eb4486

  	def generate_address_points(ctx):
  	"""
  	Generates address points from building polygons where there is an
  	addr:housenumber tag on the building. Removes those tags from the
  	building.
  	"""
  	feature_layers = ctx.feature_layers
  	zoom = ctx.nominal_zoom
  	source_layer = ctx.params.get('source_layer')
  	assert source_layer, 'generate_address_points: missing source_layer'
  	start_zoom = ctx.params.get('start_zoom', 0)
  	if zoom < start_zoom:
  	return None
  	layer = _find_layer(feature_layers, source_layer)
  	if layer is None:
  	return None
  	new_features = []
  	for feature in layer['features']:
  	shape, properties, fid = feature
  	# We only want to create address points for polygonal
  	# buildings with address tags.
  	if shape.geom_type not in ('Polygon', 'MultiPolygon'):
  	continue
  	addr_housenumber = properties.get('addr_housenumber')
  	# consider it an address if the name of the building
  	# is just a number.
  	name = properties.get('name')
  	if name is not None and digits_pattern.match(name):
  	if addr_housenumber is None:
  	addr_housenumber = properties.pop('name')
  	# and also suppress the name if it's the same as
  	# the address.
  	elif name == addr_housenumber:
  	properties.pop('name')
  	# if there's no address, then keep the feature as-is,
  	# no modifications.
  	if addr_housenumber is None:
  	continue
  	label_point = shape.representative_point()
  	# we're only interested in a very few properties for
  	# address points.
  	label_properties = dict(
  	addr_housenumber=addr_housenumber,
  	kind='address')
  	source = properties.get('source')
  	if source is not None:
  	label_properties['source'] = source
  	addr_street = properties.get('addr_street')
  	if addr_street is not None:
  	label_properties['addr_street'] = addr_street
  	oid = properties.get('id')
  	if oid is not None:
  	label_properties['id'] = oid
  	label_feature = label_point, label_properties, fid
  	new_features.append(label_feature)
  	layer['features'].extend(new_features)
  	return layer

        # we're only interested in a very few properties for
        # address points.
        label_properties = dict(
            addr_housenumber=addr_housenumber,
            kind='address')

We need to also set min_zoom=17 in that section, like:

        # we're only interested in a very few properties for
        # address points.
        label_properties = dict(
            addr_housenumber=addr_housenumber,
            min_zoom=17,
            kind='address')

[nvkelso]

PR is #2032.

[nvkelso]

Relates to tilezen/tilequeue#402.