def __search_metadata(
self, selector: SeriesSelector) -> Generator[Metadata, None, None]:
connection = self.connect()
cursor = connection.cursor()
dictionary_cursor = None
if self._config.dictionary_query is not None:
dictionary_cursor = self.connect().cursor()
cursor.execute(self._config.list_query)
series_name_index = None
for i, name in enumerate(self._config.list_columns):
if name == "series name":
series_name_index = i
if series_name_index is None:
raise InvalidMetadataError('column "series name" not found')
for row in cursor:
selector = SeriesSelector(selector.source, row[series_name_index])
metadata = Metadata(selector)
for i, name in enumerate(self._config.list_columns):
if i == series_name_index:
continue
if row[i] is None:
continue
metadata.set_field(
name,
self._metadata_value_mapper.from_source(name, row[i]))
if metadata.dictionary_name is not None and dictionary_cursor is not None:
metadata.dictionary = self.__query_dictionary(
dictionary_cursor, metadata.dictionary_name)
yield metadata
def get_metadata(self, selector: SeriesSelector) -> Metadata:
"""Read metadata from the DB-API connection."""
metadata = Metadata(selector)
if self._config.metadata_query is None:
return metadata
connection = self.connect()
cursor = connection.cursor()
query = self._config.metadata_query
params = [selector.name]
if self._config.query_string_parameters:
query = query.format(*params)
params = []
cursor.execute(query, params)
row = cursor.fetchone()
if row:
for i, name in enumerate(self._config.metadata_columns):
if row[i] is not None:
metadata.set_field(
name,
self._metadata_value_mapper.from_source(name, row[i]))
if metadata.dictionary_name is not None:
metadata.dictionary = self.__query_dictionary(
cursor, metadata.dictionary_name)
return metadata
def get_metadata(self, selector: SeriesSelector) -> Metadata:
"""Read metadata, taking any configured metadata mapping into account."""
metadata = Metadata(selector)
if self.__loaders.metadata is None:
return metadata
with self.__loaders.metadata.open() as metadata_file:
reader = csv.DictReader(metadata_file)
for row in reader:
if self.__metadata_mapper.from_kukur("series name") not in row:
raise InvalidMetadataError(
'column "series name" not found')
if (row[self.__metadata_mapper.from_kukur("series name")] !=
selector.name):
continue
for field, _ in metadata:
if self.__metadata_mapper.from_kukur(field) in row:
try:
value = row[self.__metadata_mapper.from_kukur(
field)]
metadata.set_field(
field,
self.__metadata_value_mapper.from_source(
field, value),
)
except ValueError:
pass
if metadata.dictionary_name is not None:
metadata.dictionary = self.__get_dictionary(
metadata.dictionary_name)
return metadata
def search(self,
selector: SeriesSelector) -> Generator[Metadata, None, None]:
"""Search for series matching the given selector."""
if self.__loaders.metadata is None:
return
with self.__loaders.metadata.open() as metadata_file:
reader = csv.DictReader(metadata_file)
for row in reader:
if self.__metadata_mapper.from_kukur("series name") not in row:
raise InvalidMetadataError(
'column "series name" not found')
series_name = row[self.__metadata_mapper.from_kukur(
"series name")]
metadata = None
if selector.name is not None:
if series_name == selector.name:
metadata = Metadata(
SeriesSelector(selector.source, series_name))
else:
metadata = Metadata(
SeriesSelector(selector.source, series_name))
if metadata is not None:
for field, _ in metadata:
if self.__metadata_mapper.from_kukur(field) in row:
try:
value = row[self.__metadata_mapper.from_kukur(
field)]
metadata.set_field(
field,
self.__metadata_value_mapper.from_source(
field, value),
)
except ValueError:
pass
if metadata.dictionary_name is not None:
metadata.dictionary = self.__get_dictionary(
metadata.dictionary_name)
yield metadata