🍪  Cookie Manager

Submitted by Lukas Masuch

Summary

Read and write browser cookies from Python using a dict-like interface.

Functions

cookie_manager

Create a cookie manager to read and write browser cookies from Python.

This component provides a dict-like interface for managing browser cookies. The manager must be rendered in your app (it creates a hidden component) and requires a rerun to sync cookies from the browser on first load.

The returned CookieManager implements Python's MutableMapping protocol, so you can use it like a dictionary:

• manager["name"] - get a cookie value (raises KeyError if not found)
• manager.get("name", "default") - get with a default value
• manager["name"] = "value" - set a cookie (with default options)
• del manager["name"] - delete a cookie
• "name" in manager - check if a cookie exists
• len(manager) - count of cookies
• dict(manager) - convert to a regular dict
• manager.keys(), manager.values(), manager.items() - iterate

For fine-grained control over cookie attributes (expiration, path, domain, secure, samesite), use the explicit manager.set() and manager.delete() methods instead of dict-style assignment.

Parameters:

Name	Type	Description	Default
key	str	A unique key for this component instance. Defaults to "cookie_manager". Use different keys if you need multiple independent cookie managers.	'cookie_manager'

Returns:

Type	Description
CookieManager	A CookieManager instance that provides dict-like access to cookies.

Note

• Call manager.ready() to check if cookies have synced from the browser
• Use st.stop() on first load while waiting for sync
• This can only manage JavaScript-accessible cookies (not HttpOnly)
• After setting/deleting cookies, call st.rerun() to see changes

Example:

```python
manager = cookie_manager()
if not manager.ready():
    st.stop()  # Wait for browser sync
theme = manager.get("theme", "light")
if st.button("Use dark theme"):
    manager["theme"] = "dark"
    st.rerun()
```

Example with custom cookie options:

```python
manager = cookie_manager()
if manager.ready():
    # Set cookie with 1-hour expiration
    manager.set("session", "abc123", max_age=3600, secure=True)
```

Source code in src/streamlit_extras/cookie_manager/__init__.py

@extra
def cookie_manager(*, key: str = "cookie_manager") -> CookieManager:
    """Create a cookie manager to read and write browser cookies from Python.

    This component provides a dict-like interface for managing browser cookies.
    The manager must be rendered in your app (it creates a hidden component)
    and requires a rerun to sync cookies from the browser on first load.

    The returned ``CookieManager`` implements Python's ``MutableMapping`` protocol,
    so you can use it like a dictionary:

    - ``manager["name"]`` - get a cookie value (raises ``KeyError`` if not found)
    - ``manager.get("name", "default")`` - get with a default value
    - ``manager["name"] = "value"`` - set a cookie (with default options)
    - ``del manager["name"]`` - delete a cookie
    - ``"name" in manager`` - check if a cookie exists
    - ``len(manager)`` - count of cookies
    - ``dict(manager)`` - convert to a regular dict
    - ``manager.keys()``, ``manager.values()``, ``manager.items()`` - iterate

    For fine-grained control over cookie attributes (expiration, path, domain,
    secure, samesite), use the explicit ``manager.set()`` and ``manager.delete()``
    methods instead of dict-style assignment.

    Args:
        key: A unique key for this component instance. Defaults to "cookie_manager".
            Use different keys if you need multiple independent cookie managers.

    Returns:
        A CookieManager instance that provides dict-like access to cookies.

    Note:
        - Call ``manager.ready()`` to check if cookies have synced from the browser
        - Use ``st.stop()`` on first load while waiting for sync
        - This can only manage JavaScript-accessible cookies (not HttpOnly)
        - After setting/deleting cookies, call ``st.rerun()`` to see changes

    Example:

        ```python
        manager = cookie_manager()
        if not manager.ready():
            st.stop()  # Wait for browser sync
        theme = manager.get("theme", "light")
        if st.button("Use dark theme"):
            manager["theme"] = "dark"
            st.rerun()
        ```

    Example with custom cookie options:

        ```python
        manager = cookie_manager()
        if manager.ready():
            # Set cookie with 1-hour expiration
            manager.set("session", "abc123", max_age=3600, secure=True)
        ```
    """
    return CookieManager(key=key)

Import:

from streamlit_extras.cookie_manager import cookie_manager # (1)!

1. You should add this to the top of your .py file

Examples

example

def example() -> None:
    """Example usage of the cookie_manager component."""
    st.info("This component can only manage JavaScript-accessible cookies. HttpOnly cookies are not supported.")

    manager = cookie_manager(key="demo_cookie_manager")

    if not manager.ready():
        st.info("Syncing cookies from browser. The app will be ready on the next rerun.")
        st.stop()

    st.subheader("Current cookies")
    st.json(dict(manager))

    get_col, set_col, delete_col = st.columns(3)

    with get_col:
        st.markdown("**Get cookie**")
        cookie_name = st.text_input("Cookie name", key="cookie_get_name")
        if st.button("Read cookie", key="cookie_get_button"):
            st.write(manager.get(cookie_name))

    with set_col:
        st.markdown("**Set cookie**")
        set_name = st.text_input("Name", key="cookie_set_name")
        set_value = st.text_input("Value", key="cookie_set_value")
        set_max_age = st.number_input(
            "Max age (seconds)",
            min_value=0,
            value=86400,
            step=60,
            key="cookie_set_max_age",
        )
        set_secure = st.checkbox("Secure", value=False, key="cookie_set_secure")
        set_samesite = st.selectbox(
            "SameSite",
            ["lax", "strict", "none"],
            index=0,
            key="cookie_set_samesite",
        )
        if st.button("Write cookie", key="cookie_set_button"):
            selected_samesite = cast(
                "Literal['strict', 'lax', 'none']",
                "lax" if set_samesite is None else set_samesite,
            )

            manager.set(
                set_name,
                set_value,
                max_age=int(set_max_age),
                secure=set_secure,
                samesite=selected_samesite,
            )
            st.rerun()

    with delete_col:
        st.markdown("**Delete cookie**")
        delete_name = st.text_input("Cookie to delete", key="cookie_delete_name")
        if st.button("Delete cookie", key="cookie_delete_button"):
            manager.delete(delete_name)
            st.rerun()

    st.subheader("Basic usage")
    st.code(
        """
manager = cookie_manager()

if not manager.ready():
    st.stop()  # Wait for browser sync

# Dict-like access
theme = manager.get("theme", "light")
st.write(f"Current theme: {theme}")

if st.button("Use dark theme"):
    manager["theme"] = "dark"
    st.rerun()

# Or use set() for more control
manager.set("session_id", "abc123", max_age=3600, secure=True)
""".strip(),
        language="python",
    )