diff options
| -rw-r--r-- | fnme/data.py | 34 |
1 files changed, 22 insertions, 12 deletions
diff --git a/fnme/data.py b/fnme/data.py index 11497ce..6d85f43 100644 --- a/fnme/data.py +++ b/fnme/data.py @@ -1,3 +1,4 @@ +import csv from pathlib import Path import pandas as pd @@ -14,20 +15,29 @@ def get_latest_data() -> tuple[pd.DataFrame, str | None]: cache_dir.mkdir(parents=True, exist_ok=True) - remote_last_modified = requests.head( - ENDPOINT, headers=HEADERS, timeout=10 - ).headers.get("Last-Modified") - cached_last_modified = ( timestamp_path.read_text() if timestamp_path.exists() else None ) - if not csv_path.exists() or remote_last_modified != cached_last_modified: - response = requests.get(ENDPOINT, headers=HEADERS, timeout=10) - response.raise_for_status() - last_modified = response.headers.get("Last-Modified") - csv_path.write_text(response.text, encoding="utf-8") - timestamp_path.write_text(last_modified or "") - return pd.read_csv(csv_path), last_modified + conditional_headers = { + **HEADERS, + **( + {"If-Modified-Since": cached_last_modified} + if cached_last_modified and csv_path.exists() + else {} + ), + } + + response = requests.get(ENDPOINT, headers=conditional_headers, timeout=10) + response.raise_for_status() + + if response.status_code == 304: + print(f"[*] Using cached data. Last modified: {cached_last_modified}") + return pd.read_csv(csv_path), cached_last_modified + + print("[!] Cache is stale. Refreshing.") - return pd.read_csv(csv_path), cached_last_modified + last_modified = response.headers.get("Last-Modified") + csv_path.write_text(response.text, encoding="utf-8") + timestamp_path.write_text(last_modified or "") + return pd.read_csv(csv_path), last_modified |