# 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 datetime import date, datetime, time, timedelta, timezone, tzinfo from textwrap import dedent from typing import ( TYPE_CHECKING, Any, List, Optional, Sequence, Tuple, TypeVar, Union, cast, ) from typing_extensions import Final, TypeAlias 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.errors import StreamlitAPIException from streamlit.js_number import JSNumber, JSNumberBoundsException from streamlit.proto.Slider_pb2 import Slider as SliderProto 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, get_session_state, register_widget, ) from streamlit.type_util import Key, LabelVisibility, maybe_raise_label_warnings, to_key if TYPE_CHECKING: from streamlit.delta_generator import DeltaGenerator SliderScalarT = TypeVar("SliderScalarT", int, float, date, time, datetime) Step: TypeAlias = Union[int, float, timedelta] SliderScalar: TypeAlias = Union[int, float, date, time, datetime] SliderValueGeneric: TypeAlias = Union[ SliderScalarT, Sequence[SliderScalarT], ] SliderValue: TypeAlias = Union[ SliderValueGeneric[int], SliderValueGeneric[float], SliderValueGeneric[date], SliderValueGeneric[time], SliderValueGeneric[datetime], ] SliderReturnGeneric: TypeAlias = Union[ SliderScalarT, Tuple[SliderScalarT], Tuple[SliderScalarT, SliderScalarT], ] SliderReturn: TypeAlias = Union[ SliderReturnGeneric[int], SliderReturnGeneric[float], SliderReturnGeneric[date], SliderReturnGeneric[time], SliderReturnGeneric[datetime], ] SECONDS_TO_MICROS: Final = 1000 * 1000 DAYS_TO_MICROS: Final = 24 * 60 * 60 * SECONDS_TO_MICROS UTC_EPOCH: Final = datetime(1970, 1, 1, tzinfo=timezone.utc) def _time_to_datetime(time_: time) -> datetime: # Note, here we pick an arbitrary date well after Unix epoch. # This prevents pre-epoch timezone issues (https://bugs.python.org/issue36759) # We're dropping the date from datetime later, anyway. return datetime.combine(date(2000, 1, 1), time_) def _date_to_datetime(date_: date) -> datetime: return datetime.combine(date_, time()) def _delta_to_micros(delta: timedelta) -> int: return ( delta.microseconds + delta.seconds * SECONDS_TO_MICROS + delta.days * DAYS_TO_MICROS ) def _datetime_to_micros(dt: datetime) -> int: # The frontend is not aware of timezones and only expects a UTC-based # timestamp (in microseconds). Since we want to show the date/time exactly # as it is in the given datetime object, we just set the tzinfo to UTC and # do not do any timezone conversions. Only the backend knows about # original timezone and will replace the UTC timestamp in the deserialization. utc_dt = dt.replace(tzinfo=timezone.utc) return _delta_to_micros(utc_dt - UTC_EPOCH) def _micros_to_datetime(micros: int, orig_tz: Optional[tzinfo]) -> datetime: """Restore times/datetimes to original timezone (dates are always naive)""" utc_dt = UTC_EPOCH + timedelta(microseconds=micros) # Add the original timezone. No conversion is required here, # since in the serialization, we also just replace the timestamp with UTC. return utc_dt.replace(tzinfo=orig_tz) @dataclass class SliderSerde: value: List[float] data_type: int single_value: bool orig_tz: Optional[tzinfo] def deserialize(self, ui_value: Optional[List[float]], widget_id: str = ""): if ui_value is not None: val: Any = ui_value else: # Widget has not been used; fallback to the original value, val = self.value # The widget always returns a float array, so fix the return type if necessary if self.data_type == SliderProto.INT: val = [int(v) for v in val] if self.data_type == SliderProto.DATETIME: val = [_micros_to_datetime(int(v), self.orig_tz) for v in val] if self.data_type == SliderProto.DATE: val = [_micros_to_datetime(int(v), self.orig_tz).date() for v in val] if self.data_type == SliderProto.TIME: val = [ _micros_to_datetime(int(v), self.orig_tz) .time() .replace(tzinfo=self.orig_tz) for v in val ] return val[0] if self.single_value else tuple(val) def serialize(self, v: Any) -> List[Any]: range_value = isinstance(v, (list, tuple)) value = list(v) if range_value else [v] if self.data_type == SliderProto.DATE: value = [_datetime_to_micros(_date_to_datetime(v)) for v in value] if self.data_type == SliderProto.TIME: value = [_datetime_to_micros(_time_to_datetime(v)) for v in value] if self.data_type == SliderProto.DATETIME: value = [_datetime_to_micros(v) for v in value] return value class SliderMixin: @gather_metrics("slider") def slider( self, label: str, min_value: Optional[SliderScalar] = None, max_value: Optional[SliderScalar] = None, value: Optional[SliderValue] = None, step: Optional[Step] = None, format: Optional[str] = None, 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", # TODO(harahu): Add overload definitions. The return type is # `SliderReturn`, in reality, but the return type is left as `Any` # until we have proper overload definitions in place. Otherwise the # user would have to cast the return value more often than not, which # can be annoying. ) -> Any: r"""Display a slider widget. This supports int, float, date, time, and datetime types. This also allows you to render a range slider by passing a two-element tuple or list as the `value`. The difference between `st.slider` and `st.select_slider` is that `slider` only accepts numerical or date/time data and takes a range as input, while `select_slider` accepts any datatype and takes an iterable set of options. Parameters ---------- label : str A short label explaining to the user what this slider is 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. min_value : a supported type or None The minimum permitted value. Defaults to 0 if the value is an int, 0.0 if a float, value - timedelta(days=14) if a date/datetime, time.min if a time max_value : a supported type or None The maximum permitted value. Defaults to 100 if the value is an int, 1.0 if a float, value + timedelta(days=14) if a date/datetime, time.max if a time value : a supported type or a tuple/list of supported types or None The value of the slider when it first renders. If a tuple/list of two values is passed here, then a range slider with those lower and upper bounds is rendered. For example, if set to `(1, 10)` the slider will have a selectable range between 1 and 10. Defaults to min_value. step : int/float/timedelta or None The stepping interval. Defaults to 1 if the value is an int, 0.01 if a float, timedelta(days=1) if a date/datetime, timedelta(minutes=15) if a time (or if max_value - min_value < 1 day) format : str or None A printf-style format string controlling how the interface should display numbers. This does not impact the return value. Formatter for int/float supports: %d %e %f %g %i Formatter for date/time/datetime uses Moment.js notation: https://momentjs.com/docs/#/displaying/format/ 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 An optional tooltip that gets displayed next to the slider. on_change : callable An optional callback invoked when this slider'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 slider 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 ------- int/float/date/time/datetime or tuple of int/float/date/time/datetime The current value of the slider widget. The return type will match the data type of the value parameter. Examples -------- >>> import streamlit as st >>> >>> age = st.slider('How old are you?', 0, 130, 25) >>> st.write("I'm ", age, 'years old') And here's an example of a range slider: >>> import streamlit as st >>> >>> values = st.slider( ... 'Select a range of values', ... 0.0, 100.0, (25.0, 75.0)) >>> st.write('Values:', values) This is a range time slider: >>> import streamlit as st >>> from datetime import time >>> >>> appointment = st.slider( ... "Schedule your appointment:", ... value=(time(11, 30), time(12, 45))) >>> st.write("You're scheduled for:", appointment) Finally, a datetime slider: >>> import streamlit as st >>> from datetime import datetime >>> >>> start_time = st.slider( ... "When do you start?", ... value=datetime(2020, 1, 1, 9, 30), ... format="MM/DD/YY - hh:mm") >>> st.write("Start time:", start_time) .. output:: https://doc-slider.streamlitapp.com/ height: 300px """ ctx = get_script_run_ctx() return self._slider( label=label, min_value=min_value, max_value=max_value, value=value, step=step, format=format, key=key, help=help, on_change=on_change, args=args, kwargs=kwargs, disabled=disabled, label_visibility=label_visibility, ctx=ctx, ) def _slider( self, label: str, min_value=None, max_value=None, value=None, step: Optional[Step] = None, format: Optional[str] = None, 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, ) -> SliderReturn: key = to_key(key) check_callback_rules(self.dg, on_change) check_session_state_rules(default_value=value, key=key) maybe_raise_label_warnings(label, label_visibility) if value is None: # Set value from session_state if exists. session_state = get_session_state().filtered_state # we look first to session_state value of the widget because # depending on the value (single value or list/tuple) the slider should be # initializing differently (either as range or single value slider) if key is not None and key in session_state: value = session_state[key] else: # Set value default. value = min_value if min_value is not None else 0 SUPPORTED_TYPES = { int: SliderProto.INT, float: SliderProto.FLOAT, datetime: SliderProto.DATETIME, date: SliderProto.DATE, time: SliderProto.TIME, } TIMELIKE_TYPES = (SliderProto.DATETIME, SliderProto.TIME, SliderProto.DATE) # Ensure that the value is either a single value or a range of values. single_value = isinstance(value, tuple(SUPPORTED_TYPES.keys())) range_value = isinstance(value, (list, tuple)) and len(value) in (0, 1, 2) if not single_value and not range_value: raise StreamlitAPIException( "Slider value should either be an int/float/datetime or a list/tuple of " "0 to 2 ints/floats/datetimes" ) # Simplify future logic by always making value a list if single_value: value = [value] def all_same_type(items): return len(set(map(type, items))) < 2 if not all_same_type(value): raise StreamlitAPIException( "Slider tuple/list components must be of the same type.\n" f"But were: {list(map(type, value))}" ) if len(value) == 0: data_type = SliderProto.INT else: data_type = SUPPORTED_TYPES[type(value[0])] datetime_min = time.min datetime_max = time.max if data_type == SliderProto.TIME: datetime_min = time.min.replace(tzinfo=value[0].tzinfo) datetime_max = time.max.replace(tzinfo=value[0].tzinfo) if data_type in (SliderProto.DATETIME, SliderProto.DATE): datetime_min = value[0] - timedelta(days=14) datetime_max = value[0] + timedelta(days=14) DEFAULTS = { SliderProto.INT: { "min_value": 0, "max_value": 100, "step": 1, "format": "%d", }, SliderProto.FLOAT: { "min_value": 0.0, "max_value": 1.0, "step": 0.01, "format": "%0.2f", }, SliderProto.DATETIME: { "min_value": datetime_min, "max_value": datetime_max, "step": timedelta(days=1), "format": "YYYY-MM-DD", }, SliderProto.DATE: { "min_value": datetime_min, "max_value": datetime_max, "step": timedelta(days=1), "format": "YYYY-MM-DD", }, SliderProto.TIME: { "min_value": datetime_min, "max_value": datetime_max, "step": timedelta(minutes=15), "format": "HH:mm", }, } if min_value is None: min_value = DEFAULTS[data_type]["min_value"] if max_value is None: max_value = DEFAULTS[data_type]["max_value"] if step is None: step = cast(Step, DEFAULTS[data_type]["step"]) if data_type in ( SliderProto.DATETIME, SliderProto.DATE, ) and max_value - min_value < timedelta(days=1): step = timedelta(minutes=15) if format is None: format = cast(str, DEFAULTS[data_type]["format"]) if step == 0: raise StreamlitAPIException( "Slider components cannot be passed a `step` of 0." ) # Ensure that all arguments are of the same type. slider_args = [min_value, max_value, step] int_args = all(map(lambda a: isinstance(a, int), slider_args)) float_args = all(map(lambda a: isinstance(a, float), slider_args)) # When min and max_value are the same timelike, step should be a timedelta timelike_args = ( data_type in TIMELIKE_TYPES and isinstance(step, timedelta) and type(min_value) == type(max_value) ) if not int_args and not float_args and not timelike_args: raise StreamlitAPIException( "Slider value arguments must be of matching types." "\n`min_value` has %(min_type)s type." "\n`max_value` has %(max_type)s type." "\n`step` has %(step)s type." % { "min_type": type(min_value).__name__, "max_type": type(max_value).__name__, "step": type(step).__name__, } ) # Ensure that the value matches arguments' types. all_ints = data_type == SliderProto.INT and int_args all_floats = data_type == SliderProto.FLOAT and float_args all_timelikes = data_type in TIMELIKE_TYPES and timelike_args if not all_ints and not all_floats and not all_timelikes: raise StreamlitAPIException( "Both value and arguments must be of the same type." "\n`value` has %(value_type)s type." "\n`min_value` has %(min_type)s type." "\n`max_value` has %(max_type)s type." % { "value_type": type(value).__name__, "min_type": type(min_value).__name__, "max_type": type(max_value).__name__, } ) # Ensure that min <= value(s) <= max, adjusting the bounds as necessary. min_value = min(min_value, max_value) max_value = max(min_value, max_value) if len(value) == 1: min_value = min(value[0], min_value) max_value = max(value[0], max_value) elif len(value) == 2: start, end = value if start > end: # Swap start and end, since they seem reversed start, end = end, start value = start, end min_value = min(start, min_value) max_value = max(end, max_value) else: # Empty list, so let's just use the outer bounds value = [min_value, max_value] # Bounds checks. JSNumber produces human-readable exceptions that # we simply re-package as StreamlitAPIExceptions. # (We check `min_value` and `max_value` here; `value` and `step` are # already known to be in the [min_value, max_value] range.) try: if all_ints: JSNumber.validate_int_bounds(min_value, "`min_value`") JSNumber.validate_int_bounds(max_value, "`max_value`") elif all_floats: JSNumber.validate_float_bounds(min_value, "`min_value`") JSNumber.validate_float_bounds(max_value, "`max_value`") elif all_timelikes: # No validation yet. TODO: check between 0001-01-01 to 9999-12-31 pass except JSNumberBoundsException as e: raise StreamlitAPIException(str(e)) orig_tz = None # Convert dates or times into datetimes if data_type == SliderProto.TIME: value = list(map(_time_to_datetime, value)) min_value = _time_to_datetime(min_value) max_value = _time_to_datetime(max_value) if data_type == SliderProto.DATE: value = list(map(_date_to_datetime, value)) min_value = _date_to_datetime(min_value) max_value = _date_to_datetime(max_value) # Now, convert to microseconds (so we can serialize datetime to a long) if data_type in TIMELIKE_TYPES: # Restore times/datetimes to original timezone (dates are always naive) orig_tz = ( value[0].tzinfo if data_type in (SliderProto.TIME, SliderProto.DATETIME) else None ) value = list(map(_datetime_to_micros, value)) min_value = _datetime_to_micros(min_value) max_value = _datetime_to_micros(max_value) step = _delta_to_micros(cast(timedelta, step)) # It would be great if we could guess the number of decimal places from # the `step` argument, but this would only be meaningful if step were a # decimal. As a possible improvement we could make this function accept # decimals and/or use some heuristics for floats. slider_proto = SliderProto() slider_proto.type = SliderProto.Type.SLIDER slider_proto.label = label slider_proto.format = format slider_proto.default[:] = value slider_proto.min = min_value slider_proto.max = max_value slider_proto.step = cast(float, step) slider_proto.data_type = data_type slider_proto.options[:] = [] slider_proto.form_id = current_form_id(self.dg) if help is not None: slider_proto.help = dedent(help) serde = SliderSerde(value, data_type, single_value, orig_tz) widget_state = register_widget( "slider", slider_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. slider_proto.disabled = disabled slider_proto.label_visibility.value = get_label_visibility_proto_value( label_visibility ) if widget_state.value_changed: slider_proto.value[:] = serde.serialize(widget_state.value) slider_proto.set_value = True self.dg._enqueue("slider", slider_proto) return cast(SliderReturn, widget_state.value) @property def dg(self) -> "DeltaGenerator": """Get our DeltaGenerator.""" return cast("DeltaGenerator", self)