Separate the loading of stop_times.txt and only load the stop times for the stops we are interested in.

This commit is contained in:
Nahuel Lofeudo 2023-04-16 13:49:46 +01:00
parent 855bfc3efc
commit 6b45e27539
1 changed files with 25 additions and 7 deletions

View File

@ -26,7 +26,7 @@ class GTFSClient():
print("The feed file was up to date") print("The feed file was up to date")
# Load the feed # Load the feed
self.feed = self._read_feed(feed_name, dist_units='km') self.feed = self._read_feed(feed_name, dist_units='km', stop_names = stop_names)
self.stop_ids = self.__wanted_stop_ids() self.stop_ids = self.__wanted_stop_ids()
# Schedule refresh # Schedule refresh
@ -34,7 +34,7 @@ class GTFSClient():
if update_interval_seconds and update_queue: if update_interval_seconds and update_queue:
self._refresh_thread = threading.Thread(target=lambda: every(self._update_interval_seconds, self.refresh)) self._refresh_thread = threading.Thread(target=lambda: every(self._update_interval_seconds, self.refresh))
def _read_feed(self, path: gk.Path, dist_units: str) -> gk.Feed: def _read_feed(self, path: gk.Path, dist_units: str, stop_names: list[str]) -> gk.Feed:
""" """
NOTE: This helper method was extracted from gtfs_kit.feed to modify it NOTE: This helper method was extracted from gtfs_kit.feed to modify it
to only load the stop_times for the stops we are interested in, to only load the stop_times for the stops we are interested in,
@ -69,6 +69,7 @@ class GTFSClient():
# Read files into feed dictionary of DataFrames # Read files into feed dictionary of DataFrames
feed_dict = {table: None for table in gk.cs.GTFS_REF["table"]} feed_dict = {table: None for table in gk.cs.GTFS_REF["table"]}
stop_times_p = None
for p in src_path.iterdir(): for p in src_path.iterdir():
table = p.stem table = p.stem
# Skip empty files, irrelevant files, and files with no data # Skip empty files, irrelevant files, and files with no data
@ -78,11 +79,28 @@ class GTFSClient():
and p.suffix == ".txt" and p.suffix == ".txt"
and table in feed_dict and table in feed_dict
): ):
# utf-8-sig gets rid of the byte order mark (BOM); if p.name == "stop_times.txt":
# see http://stackoverflow.com/questions/17912307/u-ufeff-in-python-string # Defer the loading of stop_times.txt until after the stop IDs are known
df = pd.read_csv(p, dtype=gk.cs.DTYPE, encoding="utf-8-sig") stop_times_p = p
if not df.empty: else:
feed_dict[table] = gk.cn.clean_column_names(df) # utf-8-sig gets rid of the byte order mark (BOM);
# see http://stackoverflow.com/questions/17912307/u-ufeff-in-python-string
df = pd.read_csv(p, dtype=gk.cs.DTYPE, encoding="utf-8-sig")
if not df.empty:
feed_dict[table] = gk.cn.clean_column_names(df)
# Finally, load stop_times.txt
if stop_times_p:
# Obtain the list of IDs of the desired stops. This is similar to what __wanted_stop_ids() does,
# but without a dependency on a fully formed feed object
wanted_stop_ids = feed_dict.get("stops")[feed_dict.get("stops")["stop_name"].isin(stop_names)]["stop_id"]
iter_csv = pd.read_csv(stop_times_p, iterator=True, chunksize=1000)
df = pd.concat([chunk[chunk["stop_id"].isin(wanted_stop_ids)] for chunk in iter_csv])
#df = pd.read_csv(stop_times_p, dtype=gk.cs.DTYPE, encoding="utf-8-sig")
if not df.empty:
feed_dict[stop_times_p.stem] = gk.cn.clean_column_names(df)
feed_dict["dist_units"] = dist_units feed_dict["dist_units"] = dist_units