fastf1 Failing to Load Session Data

Using Streamlit
1

I have an app that’s failing to load data from the fastf1 api. It’s only an error when using my deployed app, but now when used locally. The app is f1-analyzer.streamlit.app and the repo GitHub - cejaChris/f1-analyzer · GitHub.

This is what shows in the console…

core INFO Loading data for Japanese Grand Prix - Practice 1 [v3.8.3]

req INFO No cached data found for session_info. Loading data...

_api INFO Fetching session info data...

logger WARNING Failed to load session info data!

req INFO No cached data found for driver_info. Loading data...

_api INFO Fetching driver list...

core WARNING Failed to load extended driver information!

req INFO No cached data found for session_status_data. Loading data...

_api INFO Fetching session status data...

logger WARNING Failed to load session status data!

req INFO No cached data found for track_status_data. Loading data...

_api INFO Fetching track status data...

logger WARNING Failed to load track status data!

req INFO No cached data found for _extended_timing_data. Loading data...

_api INFO Fetching timing data...

logger WARNING Failed to load timing data!

req INFO No cached data found for car_data. Loading data...

_api INFO Fetching car data...

core WARNING Car telemetry data is unavailable!

req INFO No cached data found for position_data. Loading data...

_api INFO Fetching position data...

core WARNING Car position data is unavailable!

core WARNING Failed to determine `Session.t0_date`!

req INFO No cached data found for weather_data. Loading data...

_api INFO Fetching weather data...

logger WARNING Failed to load weather data!

req INFO No cached data found for race_control_messages. Loading data...

_api INFO Fetching race control messages...

logger WARNING Failed to load race control messages!

core INFO Finished loading data for 22 drivers: ['12', '81', '16', '63', '1', '44', '10', '3', '30', '31', '27', '6', '5', '41', '55', '43', '11', '14', '77', '23', '18', '87']

2

Hey there, thanks for sharing your question and welcome to the Streamlit community! :vertical_traffic_light: It looks like your app works locally but fails to load data from the fastf1 API when deployed on Streamlit Community Cloud. This is a common scenario—many APIs work locally but run into issues in cloud deployments due to network restrictions, missing dependencies, or resource limits.

My understanding is that Streamlit Community Cloud restricts outbound network requests to certain domains and may block or rate-limit requests to some APIs, especially if they’re not on an allowlist or if the API requires authentication, custom headers, or specific user agents. Additionally, if your app is making many requests or downloading large datasets, you could be hitting resource limits or timeouts, which are stricter in the cloud than locally. There’s no explicit mention in the docs of fastf1 being blocked, but similar issues have been reported with other APIs and web scraping libraries. You might also want to check if your app is using caching (st.cache_data) to avoid repeated downloads, as this can help with both speed and resource usage in the cloud environment.

For more details, see the official docs on resource limits, deployment issues, and API/networking considerations. If you can, try logging the actual HTTP error or exception—sometimes it’s a DNS, SSL, or timeout issue. If you’re able, share a minimum reproducible example or more logs for the community to help debug! And if anyone else has run into fastf1 API issues on Community Cloud, please jump in and share your experience.

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