Windows Terminal progress indicators

[vsalvino]

I recently discovered that the new Windows Terminal will read special escape sequences to trigger progress states in the UI. This is quite a "shiny" animation and takes the integration to the next level, as the progress meter shows in the Windows task bar and title bar.

A quick proof of concept shows that this in fact works well with Python!

Details: microsoft/terminal#8055

Proof of concept:

import time

# Indeterminate
print("Waiting 5 seconds...", "\033]9;4;3;0\033\\")
time.sleep(5)

# Reset
print("Reset.", "\033]9;4;0;0\033\\")

# Progress 0-100
for i in range(101):
    print(f"\rLoading {i}/100", end="")
    print(f"\033]9;4;1;{i}\033\\", end="")
    time.sleep(0.05)

# Reset
print("\nDone.", "\033]9;4;0;\033\\")

[vsalvino]

More concrete proof of concept. This is a simple extension to the Progress class which handles printing the codes when tasks are updated.

The one thing I could see being a problem here, is when there are multiple running tasks. Ideally the Progress object should determine the average status of all running tasks, and use that for the OSC progress indicator. But this example works if tasks are sequential.

Perhaps a simpler idea would be to only use the indeterminate OSC while the Progress object is in use.

from rich.console import WINDOWS
import rich.progress


class Progress(rich.progress.Progress):
    """
    Provides extra support for Windows Terminal and ConEmu to set operating
    system codes (OSC) for progress indicators.
    """

    def add_task(self, *args, **kwargs) -> rich.progress.TaskID:
        """
        Override to initiate OSC progress indicator.
        """
        tid = super().add_task(*args, **kwargs)

        # Only continue on supported systems.
        if not WINDOWS or self.console.legacy_windows:
            return tid

        task = self._tasks[tid]

        # Set indeterminate status if no total.
        if task.total is None:
            self.console.print("\x1b]9;4;3;0\x1b\\", end="")

        # If we have a total, show the percentage.
        elif task.total:
            percent = int(task.percentage)
            self.console.print(f"\x1b]9;4;1;{percent}\x1b\\", end="")

        return tid

    def update(self, task_id: rich.progress.TaskID, *args, **kwargs) -> None:
        """
        Override to reset OSC progress, or update the percentage.
        """
        super().update(task_id, *args, **kwargs)

        # Only continue on supported systems.
        if not WINDOWS or self.console.legacy_windows:
            return

        task = self._tasks[task_id]

        # Reset if completed.
        if task.total and task.completed >= task.total:
            self.console.print("\x1b]9;4;0;0\x1b\\", end="")

        # If we have a total, show the percentage.
        elif task.total:
            percent = int(task.percentage)
            self.console.print(f"\x1b]9;4;1;{percent}\x1b\\", end="")