# Copyright (c) Streamlit Inc. (2018-2022) Snowflake Inc. (2022-2026) # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. """Handle App logos.""" from __future__ import annotations from typing import Literal from streamlit import url_util from streamlit.elements.lib.image_utils import AtomicImage, image_to_url from streamlit.elements.lib.layout_utils import LayoutConfig from streamlit.errors import StreamlitAPIException from streamlit.proto.ForwardMsg_pb2 import ForwardMsg from streamlit.proto.Logo_pb2 import Logo as LogoProto from streamlit.runtime.metrics_util import gather_metrics from streamlit.runtime.scriptrunner_utils.script_run_context import get_script_run_ctx from streamlit.string_util import is_emoji, validate_material_icon def _invalid_logo_text(field_name: str) -> str: return ( f"The {field_name} passed to st.logo is invalid - See " "[documentation](https://docs.streamlit.io/develop/api-reference/media/st.logo) " "for more information on valid types" ) def _process_logo_image( image: AtomicImage | str, image_id: str ) -> tuple[LogoProto.ImageType.ValueType, str]: """Detects the image type and prepares the image data for the frontend. Parameters ---------- image : The image that was provided by the user. Can be an image file, emoji, or material icon string. image_id : str The image ID used when serving local images via the media file manager. Returns ------- tuple[ImageType, str] The detected image type and the prepared image data. Raises ------ StreamlitAPIException If the image is an empty string or a plain text string that is not a valid file path, URL, emoji, or material icon. """ ImageType = LogoProto.ImageType # noqa: N806 # Check if it's a material icon if isinstance(image, str) and image.startswith(":material"): return ImageType.ICON, validate_material_icon(image) # Check if it's an emoji if isinstance(image, str) and is_emoji(image): return ImageType.EMOJI, image # Otherwise, treat it as an image file image_url = image_to_url( image, layout_config=LayoutConfig(width="content"), clamp=False, channels="RGB", output_format="auto", image_id=image_id, ) return ImageType.IMAGE, image_url @gather_metrics("logo") def logo( image: AtomicImage | str, *, # keyword-only args: size: Literal["small", "medium", "large"] = "medium", link: str | None = None, icon_image: AtomicImage | str | None = None, ) -> None: r""" Renders a logo in the upper-left corner of your app and its sidebar. If ``st.logo`` is called multiple times within a page, Streamlit will render the image passed in the last call. For the most consistent results, call ``st.logo`` early in your page script and choose an image that works well in both light and dark mode. Avoid empty margins around your image. If your logo does not work well for both light and dark mode, consider setting the theme and hiding the settings menu from users with the `configuration option `_ ``client.toolbarMode="minimal"``. If a user clicks the logo, they are redirected to your app's home page. Parameters ---------- image: Anything supported by st.image (except list) or str The image to display in the upper-left corner of your app and its sidebar. If ``icon_image`` is also provided, then Streamlit will only display ``image`` in the sidebar. ``image`` can be any of the types supported by |st.image|_ except a list. Additionally, the following strings are valid: - A single-character emoji. For example, you can set ``image="🏠"`` or ``image="🚀"``. Emoji short codes are not supported. - An icon from the Material Symbols library (rounded style) in the format ``":material/icon_name:"`` where "icon_name" is the name of the icon in snake case. For example, ``image=":material/home:"`` will display the Home icon. Find additional icons in the `Material Symbols \ `_ font library. Streamlit scales the image to a max height set by ``size`` and a max width to fit within the sidebar. .. |st.image| replace:: ``st.image`` .. _st.image: https://docs.streamlit.io/develop/api-reference/media/st.image size: "small", "medium", or "large" The size of the image displayed in the upper-left corner of the app and its sidebar. The possible values are as follows: - ``"small"``: 20px max height - ``"medium"`` (default): 24px max height - ``"large"``: 32px max height link : str or None The external URL to open when a user clicks on the logo. The URL must start with "\http://" or "\https://". If ``link`` is ``None`` (default), the logo will not include a hyperlink. icon_image: Anything supported by st.image (except list), str, or None An optional, typically smaller image to replace ``image`` in the upper-left corner when the sidebar is closed. This can be any of the types allowed for the ``image`` parameter. If ``icon_image`` is ``None`` (default), Streamlit will always display ``image`` in the upper-left corner, regardless of whether the sidebar is open or closed. Otherwise, Streamlit will render ``icon_image`` in the upper-left corner of the app when the sidebar is closed. Streamlit scales the image to a max height set by ``size`` and a max width to fit within the sidebar. If the sidebar is closed, the max width is retained from when it was last open. For best results, pass a wide or horizontal image to ``image`` and a square image to ``icon_image``. Or, pass a square image to ``image`` and leave ``icon_image=None``. Examples -------- A common design practice is to use a wider logo in the sidebar, and a smaller, icon-styled logo in your app's main body. >>> import streamlit as st >>> >>> st.logo( ... LOGO_URL_LARGE, ... link="https://streamlit.io/gallery", ... icon_image=LOGO_URL_SMALL, ... ) Try switching logos around in the following example: >>> import streamlit as st >>> >>> HORIZONTAL_RED = "images/horizontal_red.png" >>> ICON_RED = "images/icon_red.png" >>> HORIZONTAL_BLUE = "images/horizontal_blue.png" >>> ICON_BLUE = "images/icon_blue.png" >>> >>> options = [HORIZONTAL_RED, ICON_RED, HORIZONTAL_BLUE, ICON_BLUE] >>> sidebar_logo = st.selectbox("Sidebar logo", options, 0) >>> main_body_logo = st.selectbox("Main body logo", options, 1) >>> >>> st.logo(sidebar_logo, icon_image=main_body_logo) >>> st.sidebar.markdown("Hi!") .. output:: https://doc-logo.streamlit.app/ height: 300px """ ctx = get_script_run_ctx() if ctx is None: return fwd_msg = ForwardMsg() try: image_type, image_value = _process_logo_image(image, "logo") fwd_msg.logo.image = image_value fwd_msg.logo.image_type = image_type except Exception as ex: raise StreamlitAPIException(_invalid_logo_text("image")) from ex if link: # Handle external links: if url_util.is_url(link, ("http", "https")): fwd_msg.logo.link = link else: raise StreamlitAPIException( f"Invalid link: {link} - the link param supports external links only and must " f"start with either http:// or https://." ) if icon_image: try: icon_image_type, icon_image_value = _process_logo_image( icon_image, "icon-image" ) fwd_msg.logo.icon_image = icon_image_value fwd_msg.logo.icon_image_type = icon_image_type except Exception as ex: raise StreamlitAPIException(_invalid_logo_text("icon_image")) from ex def validate_size(size: str) -> str: if isinstance(size, str): image_size = size.lower() valid_sizes = ["small", "medium", "large"] if image_size in valid_sizes: return image_size raise StreamlitAPIException( f'The size argument to st.logo must be "small", "medium", or "large". \n' f"The argument passed was {size}." ) fwd_msg.logo.size = validate_size(size) ctx.enqueue(fwd_msg)