# Copyright (c) Streamlit Inc. (2018-2022) Snowflake Inc. (2022) # # 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. from dataclasses import dataclass from textwrap import dedent from typing import TYPE_CHECKING, List, Optional, cast from streamlit.elements.form import current_form_id from streamlit.elements.utils import ( check_callback_rules, check_session_state_rules, get_label_visibility_proto_value, ) from streamlit.proto.CameraInput_pb2 import CameraInput as CameraInputProto from streamlit.proto.Common_pb2 import FileUploaderState as FileUploaderStateProto from streamlit.proto.Common_pb2 import UploadedFileInfo as UploadedFileInfoProto from streamlit.runtime.metrics_util import gather_metrics from streamlit.runtime.scriptrunner import ScriptRunContext, get_script_run_ctx from streamlit.runtime.state import ( WidgetArgs, WidgetCallback, WidgetKwargs, register_widget, ) from streamlit.runtime.uploaded_file_manager import UploadedFile, UploadedFileRec from streamlit.type_util import Key, LabelVisibility, maybe_raise_label_warnings, to_key if TYPE_CHECKING: from streamlit.delta_generator import DeltaGenerator SomeUploadedSnapshotFile = Optional[UploadedFile] def _get_file_recs_for_camera_input_widget( widget_id: str, widget_value: Optional[FileUploaderStateProto] ) -> List[UploadedFileRec]: if widget_value is None: return [] ctx = get_script_run_ctx() if ctx is None: return [] uploaded_file_info = widget_value.uploaded_file_info if len(uploaded_file_info) == 0: return [] active_file_ids = [f.id for f in uploaded_file_info] # Grab the files that correspond to our active file IDs. return ctx.uploaded_file_mgr.get_files( session_id=ctx.session_id, widget_id=widget_id, file_ids=active_file_ids, ) @dataclass class CameraInputSerde: def serialize( self, snapshot: SomeUploadedSnapshotFile, ) -> FileUploaderStateProto: state_proto = FileUploaderStateProto() ctx = get_script_run_ctx() if ctx is None: return state_proto # ctx.uploaded_file_mgr._file_id_counter stores the id to use for # the *next* uploaded file, so the current highest file id is the # counter minus 1. state_proto.max_file_id = ctx.uploaded_file_mgr._file_id_counter - 1 if not snapshot: return state_proto file_info: UploadedFileInfoProto = state_proto.uploaded_file_info.add() file_info.id = snapshot.id file_info.name = snapshot.name file_info.size = snapshot.size return state_proto def deserialize( self, ui_value: Optional[FileUploaderStateProto], widget_id: str ) -> SomeUploadedSnapshotFile: file_recs = _get_file_recs_for_camera_input_widget(widget_id, ui_value) if len(file_recs) == 0: return_value = None else: return_value = UploadedFile(file_recs[0]) return return_value class CameraInputMixin: @gather_metrics("camera_input") def camera_input( self, label: str, key: Optional[Key] = None, help: Optional[str] = None, on_change: Optional[WidgetCallback] = None, args: Optional[WidgetArgs] = None, kwargs: Optional[WidgetKwargs] = None, *, # keyword-only arguments: disabled: bool = False, label_visibility: LabelVisibility = "visible", ) -> SomeUploadedSnapshotFile: r"""Display a widget that returns pictures from the user's webcam. Parameters ---------- label : str A short label explaining to the user what this widget is used for. The label can optionally contain Markdown and supports the following elements: Bold, Italics, Strikethroughs, Inline Code, Emojis, and Links. This also supports: * Emoji shortcodes, such as ``:+1:`` and ``:sunglasses:``. For a list of all supported codes, see https://share.streamlit.io/streamlit/emoji-shortcodes. * LaTeX expressions, by wrapping them in "$" or "$$" (the "$$" must be on their own lines). Supported LaTeX functions are listed at https://katex.org/docs/supported.html. * Colored text, using the syntax ``:color[text to be colored]``, where ``color`` needs to be replaced with any of the following supported colors: blue, green, orange, red, violet. Unsupported elements are unwrapped so only their children (text contents) render. Display unsupported elements as literal characters by backslash-escaping them. E.g. ``1\. Not an ordered list``. For accessibility reasons, you should never set an empty label (label="") but hide it with label_visibility if needed. In the future, we may disallow empty labels by raising an exception. key : str or int An optional string or integer to use as the unique key for the widget. If this is omitted, a key will be generated for the widget based on its content. Multiple widgets of the same type may not share the same key. help : str A tooltip that gets displayed next to the camera input. on_change : callable An optional callback invoked when this camera_input's value changes. args : tuple An optional tuple of args to pass to the callback. kwargs : dict An optional dict of kwargs to pass to the callback. disabled : bool An optional boolean, which disables the camera input if set to True. The default is False. This argument can only be supplied by keyword. label_visibility : "visible" or "hidden" or "collapsed" The visibility of the label. If "hidden", the label doesn't show but there is still empty space for it above the widget (equivalent to label=""). If "collapsed", both the label and the space are removed. Default is "visible". This argument can only be supplied by keyword. Returns ------- None or UploadedFile The UploadedFile class is a subclass of BytesIO, and therefore it is "file-like". This means you can pass them anywhere where a file is expected. Examples -------- >>> import streamlit as st >>> >>> picture = st.camera_input("Take a picture") >>> >>> if picture: ... st.image(picture) """ ctx = get_script_run_ctx() return self._camera_input( label=label, key=key, help=help, on_change=on_change, args=args, kwargs=kwargs, disabled=disabled, label_visibility=label_visibility, ctx=ctx, ) def _camera_input( self, label: str, key: Optional[Key] = None, help: Optional[str] = None, on_change: Optional[WidgetCallback] = None, args: Optional[WidgetArgs] = None, kwargs: Optional[WidgetKwargs] = None, *, # keyword-only arguments: disabled: bool = False, label_visibility: LabelVisibility = "visible", ctx: Optional[ScriptRunContext] = None, ) -> SomeUploadedSnapshotFile: key = to_key(key) check_callback_rules(self.dg, on_change) check_session_state_rules(default_value=None, key=key, writes_allowed=False) maybe_raise_label_warnings(label, label_visibility) camera_input_proto = CameraInputProto() camera_input_proto.label = label camera_input_proto.form_id = current_form_id(self.dg) if help is not None: camera_input_proto.help = dedent(help) serde = CameraInputSerde() camera_input_state = register_widget( "camera_input", camera_input_proto, user_key=key, on_change_handler=on_change, args=args, kwargs=kwargs, deserializer=serde.deserialize, serializer=serde.serialize, ctx=ctx, ) # This needs to be done after register_widget because we don't want # the following proto fields to affect a widget's ID. camera_input_proto.disabled = disabled camera_input_proto.label_visibility.value = get_label_visibility_proto_value( label_visibility ) ctx = get_script_run_ctx() camera_image_input_state = serde.serialize(camera_input_state.value) uploaded_shapshot_info = camera_image_input_state.uploaded_file_info if ctx is not None and len(uploaded_shapshot_info) != 0: newest_file_id = camera_image_input_state.max_file_id active_file_ids = [f.id for f in uploaded_shapshot_info] ctx.uploaded_file_mgr.remove_orphaned_files( session_id=ctx.session_id, widget_id=camera_input_proto.id, newest_file_id=newest_file_id, active_file_ids=active_file_ids, ) self.dg._enqueue("camera_input", camera_input_proto) return camera_input_state.value @property def dg(self) -> "DeltaGenerator": """Get our DeltaGenerator.""" return cast("DeltaGenerator", self)