toasty/progress.py: add this

toasty/progress.py

@@ -0,0 +1,45 @@
+# -*- mode: python; coding: utf-8 -*-
+# Copyright 2022 the AAS WorldWide Telescope project
+# Licensed under the MIT License.
+
+"""Utilities for progress reporting
+
+This module provides an extremely thin wrapper around TQDM that avoids ``\r``
+output when stdout is not a terminal, for producing more easily greppable logs.
+It also reduces the update frequency to reduce log volume.
+
+"""
+
+__all__ = """
+progress_bar
+""".split()
+
+from contextlib import contextmanager
+import sys
+
+from tqdm import tqdm
+
+NON_TTY_INTERVAL = 30
+
+
+@contextmanager
+def progress_bar(total=None, show=None):
+    assert total is not None
+    assert show is not None
+
+    args = dict(
+        total=total,
+        disable=not show,
+    )
+
+    if not sys.stdout.isatty():
+        args["bar_format"] = "{l_bar}{bar}{r_bar}\n"
+        args["mininterval"] = NON_TTY_INTERVAL
+        args["maxinterval"] = NON_TTY_INTERVAL
+
+    try:
+        with tqdm(**args) as progress:
+            yield progress
+    finally:
+        if show and sys.stdout.isatty():
+            print()