Troubleshooting

Sorry to hear you're having issues! Please take a look at some frequently asked questions and issues below. If you cannot find an answer to your issue, please post on our Community forum so that our engineers or community members can help you.

Table of contents

1. General help
2. Deploying apps
3. Sharing and accessing apps
4. Data and app security
5. GitHub integration
6. Limitations and known issues

General help

How can I get help with my app?

If you have any questions, feedback, run into any issues, or need to reach us, you can ask on our Community forum. This is best suited for any questions related to the open source library and Community Cloud - debugging code, deployment, resource limits, etc.

Deploying apps

My repo isn't showing on the Deploy page

It's possible it just isn't showing up even though it is already there. Try typing it in. If we don't recognize it, you'll see the message below with a link to click and give access.

If for some reason that doesn't work, please try logging out and back in again to make sure the change took effect. And if that doesn't work - please let us know and we'll get you sorted!

It won't let me deploy the app

To deploy an app for the first time you must have admin-level access to the repo in GitHub. Please check with your administrator to make sure you have that access. If not, please ask them to deploy for the first time (we need this in order to establish webhooks for continuous integration) and from there you can then push updates to the app.

I need to set a specific Python version for my app

When deploying an app, under advanced settings, you can choose which version of Python you wish your app to use.

How do I store files locally?

If you want to store your data locally as opposed to in a database, you can store the file in your GitHub repository. Streamlit is just python, so you can read the file using:

pandas.read_csv("data.csv") or open("data.csv")

My app is running into issues while deploying

Check your Cloud logs by clicking on the "Manage app" expander in the bottom right corner of your screen. Often the trouble is due to a dependency not being declared. See here for more information on dependency management.

If that's not the issue, then please send the logs and warning you are seeing to our Community forum and we'll help get you sorted!

My app is hitting resource limits / my app is running very slowly

If your app is running slowly or you're hitting the 'Argh' page, we first highly recommend going through and implementing the suggestions in the following blog posts to prevent your app from hitting the resource limits and to detect if your Streamlit app leaks memory:

• Common app problems: Resource limits
• 3 steps to fix app memory leaks

If you're still having issues, click here to learn more about resource limits.

Can I get a custom URL for my app?

Yes! You can find instructions for setting a custom subdomain here.

Sharing and accessing apps

How do I add viewers to my Streamlit apps?

Viewer auth allows you to restrict the viewers of your private app. To access your app, users have to authenticate using an email-based passwordless login or Google OAuth. To learn more about how to share your public and private apps with viewers, click here.

Do viewers need access to the GitHub repo?

Nope! You only need access to the GitHub repo if you want to push changes to the app.

What will unauthorized/logged out viewers see when they view my app?

A 404 error is displayed to unauthorized viewers to avoid providing any unnecessary information about your app to unintended viewers. Users who satisfy any of the following conditions will see a 404 error when attempting to view your app after you have configured viewer auth:

• User is not logged in with their primary identity.
• User is not included in the list of allowed viewers provided in the app settings.
• User lacks read access to your app's GitHub repo.
• User has read access to your app's GitHub repo but is not enrolled in Streamlit Community Cloud.

I've added someone to the viewer list but they still see a 404 error when attempting to view the app

If a user is still seeing a 404 error after their email address has been added to the viewer list, we recommend that you:

• Check that the user did not log into a different Google account via Single Sign-On (if you have added their work email address to the viewer list, ask the user to check that they are not logged into their personal Google account, and vice versa).
• Check that the user has navigated to the correct URL.
• Check that the user's email address has been entered correctly in the viewer list.
• Reach out on our Community forum and we will be happy to help.

Data and app security

How will Streamlit secure my data?

Streamlit takes a number of industry best-practice measures to ensure your code, data, and apps are all secure. Read more in our Trust and Security memo.

How do I set up SSO for my organization?

Community Cloud uses Google OAuth, by default. If you use Google for authentication you're all set.

Billing and administration

The Community Cloud is a free service. You don't have to worry about setting up billing or being charged.

GitHub integration

Why does Streamlit require additional OAuth scope?

In order to deploy your app, Streamlit requires access to your app's source code in GitHub and also the ability to manage the public keys associated with the repositories. The default GitHub OAuth scopes are sufficient to work with apps in public GitHub repositories. However, in order to work with apps in private GitHub repositories, Streamlit requires the additional repo OAuth scope from GitHub. We recognize that this scope provides Streamlit with extra permissions that we do not really need, and which, as people who prize security, we'd rather not even be granted. Alas, we need to work with the APIs we are provided by GitHub.

After deploying my private-repo app, I received an email from GitHub saying a new public key was added to my repo. Is this expected?

This is the expected behavior. When you try to deploy an app that lives in a private repo, Streamlit Community Cloud needs to get access to that repo somehow. For this, we create a read-only GitHub Deploy Key then access your repo using a public SSH key. When we set this up, GitHub notifies admins of the repo that the key was created as a security measure.

What happens when a user's permissions change on GitHub?

Once a user is added to a repository on GitHub, it will take at most 15 minutes before they can deploy the app on Cloud. If a user is removed from a repository on GitHub, it will take at most 15 minutes before their permissions to manage the app from that repository are revoked.

Limitations and known issues

Here are some limitations and known issues that we're actively working to resolve.

• When you print something to the Cloud logs, you may need to do a sys.stdout.flush() before it shows up.

• Matplotlib doesn't work well with threads. So if you're using Matplotlib you should wrap your code with locks as shown in the snippet below. This Matplotlib bug is more prominent when you share your app apps since you're more likely to get more concurrent users then.

  from matplotlib.backends.backend_agg import RendererAgg
  _lock = RendererAgg.lock
  
  with _lock:
    fig.title('This is a figure)')
    fig.plot([1,20,3,40])
    st.pyplot(fig)
  

• All apps are hosted in the United States. This is currently not configurable.