Source code for rich.progress_bar

import math
from functools import lru_cache
from time import monotonic
from typing import Iterable, List, Optional

from .color import Color, blend_rgb
from .color_triplet import ColorTriplet
from .console import Console, ConsoleOptions, RenderResult
from .jupyter import JupyterMixin
from .measure import Measurement
from .segment import Segment
from .style import Style, StyleType

# Number of characters before 'pulse' animation repeats
PULSE_SIZE = 20


[docs]class ProgressBar(JupyterMixin): """Renders a (progress) bar. Used by rich.progress. Args: total (float, optional): Number of steps in the bar. Defaults to 100. Set to None to render a pulsing animation. completed (float, optional): Number of steps completed. Defaults to 0. width (int, optional): Width of the bar, or ``None`` for maximum width. Defaults to None. pulse (bool, optional): Enable pulse effect. Defaults to False. Will pulse if a None total was passed. style (StyleType, optional): Style for the bar background. Defaults to "bar.back". complete_style (StyleType, optional): Style for the completed bar. Defaults to "bar.complete". finished_style (StyleType, optional): Style for a finished bar. Defaults to "bar.finished". pulse_style (StyleType, optional): Style for pulsing bars. Defaults to "bar.pulse". animation_time (Optional[float], optional): Time in seconds to use for animation, or None to use system time. """ def __init__( self, total: Optional[float] = 100.0, completed: float = 0, width: Optional[int] = None, pulse: bool = False, style: StyleType = "bar.back", complete_style: StyleType = "bar.complete", finished_style: StyleType = "bar.finished", pulse_style: StyleType = "bar.pulse", animation_time: Optional[float] = None, ): self.total = total self.completed = completed self.width = width self.pulse = pulse self.style = style self.complete_style = complete_style self.finished_style = finished_style self.pulse_style = pulse_style self.animation_time = animation_time self._pulse_segments: Optional[List[Segment]] = None def __repr__(self) -> str: return f"<Bar {self.completed!r} of {self.total!r}>" @property def percentage_completed(self) -> Optional[float]: """Calculate percentage complete.""" if self.total is None: return None completed = (self.completed / self.total) * 100.0 completed = min(100, max(0.0, completed)) return completed @lru_cache(maxsize=16) def _get_pulse_segments( self, fore_style: Style, back_style: Style, color_system: str, no_color: bool, ascii: bool = False, ) -> List[Segment]: """Get a list of segments to render a pulse animation. Returns: List[Segment]: A list of segments, one segment per character. """ bar = "-" if ascii else "━" segments: List[Segment] = [] if color_system not in ("standard", "eight_bit", "truecolor") or no_color: segments += [Segment(bar, fore_style)] * (PULSE_SIZE // 2) segments += [Segment(" " if no_color else bar, back_style)] * ( PULSE_SIZE - (PULSE_SIZE // 2) ) return segments append = segments.append fore_color = ( fore_style.color.get_truecolor() if fore_style.color else ColorTriplet(255, 0, 255) ) back_color = ( back_style.color.get_truecolor() if back_style.color else ColorTriplet(0, 0, 0) ) cos = math.cos pi = math.pi _Segment = Segment _Style = Style from_triplet = Color.from_triplet for index in range(PULSE_SIZE): position = index / PULSE_SIZE fade = 0.5 + cos((position * pi * 2)) / 2.0 color = blend_rgb(fore_color, back_color, cross_fade=fade) append(_Segment(bar, _Style(color=from_triplet(color)))) return segments
[docs] def update(self, completed: float, total: Optional[float] = None) -> None: """Update progress with new values. Args: completed (float): Number of steps completed. total (float, optional): Total number of steps, or ``None`` to not change. Defaults to None. """ self.completed = completed self.total = total if total is not None else self.total
def _render_pulse( self, console: Console, width: int, ascii: bool = False ) -> Iterable[Segment]: """Renders the pulse animation. Args: console (Console): Console instance. width (int): Width in characters of pulse animation. Returns: RenderResult: [description] Yields: Iterator[Segment]: Segments to render pulse """ fore_style = console.get_style(self.pulse_style, default="white") back_style = console.get_style(self.style, default="black") pulse_segments = self._get_pulse_segments( fore_style, back_style, console.color_system, console.no_color, ascii=ascii ) segment_count = len(pulse_segments) current_time = ( monotonic() if self.animation_time is None else self.animation_time ) segments = pulse_segments * (int(width / segment_count) + 2) offset = int(-current_time * 15) % segment_count segments = segments[offset : offset + width] yield from segments def __rich_console__( self, console: Console, options: ConsoleOptions ) -> RenderResult: width = min(self.width or options.max_width, options.max_width) ascii = options.legacy_windows or options.ascii_only should_pulse = self.pulse or self.total is None if should_pulse: yield from self._render_pulse(console, width, ascii=ascii) return completed: Optional[float] = ( min(self.total, max(0, self.completed)) if self.total is not None else None ) bar = "-" if ascii else "━" half_bar_right = " " if ascii else "╸" half_bar_left = " " if ascii else "╺" complete_halves = ( int(width * 2 * completed / self.total) if self.total and completed is not None else width * 2 ) bar_count = complete_halves // 2 half_bar_count = complete_halves % 2 style = console.get_style(self.style) is_finished = self.total is None or self.completed >= self.total complete_style = console.get_style( self.finished_style if is_finished else self.complete_style ) _Segment = Segment if bar_count: yield _Segment(bar * bar_count, complete_style) if half_bar_count: yield _Segment(half_bar_right * half_bar_count, complete_style) if not console.no_color: remaining_bars = width - bar_count - half_bar_count if remaining_bars and console.color_system is not None: if not half_bar_count and bar_count: yield _Segment(half_bar_left, style) remaining_bars -= 1 if remaining_bars: yield _Segment(bar * remaining_bars, style) def __rich_measure__( self, console: Console, options: ConsoleOptions ) -> Measurement: return ( Measurement(self.width, self.width) if self.width is not None else Measurement(4, options.max_width) )
if __name__ == "__main__": # pragma: no cover console = Console() bar = ProgressBar(width=50, total=100) import time console.show_cursor(False) for n in range(0, 101, 1): bar.update(n) console.print(bar) console.file.write("\r") time.sleep(0.05) console.show_cursor(True) console.print()