add a --progress progress-bar option

which only works in conjunction with --batch, not STDIN, as it needs to
read over the file to count the number of goal statements.

Care is also taken that a plain file, not a FIFO, is passed to --batch.

Author: rolandwalker

changelog.md

@@ -4,6 +4,7 @@ Upcoming (TBD)
 Features
 ---------
 * Respond to `-h` alone with the helpdoc.
+* Add a `--progress` progress-bar option with `--batch`.
 
 
 Bug Fixes

mycli/main.py

@@ -35,6 +35,7 @@
 import clickdc
 from configobj import ConfigObj
 import keyring
+import prompt_toolkit
 from prompt_toolkit import print_formatted_text
 from prompt_toolkit.application.current import get_app
 from prompt_toolkit.auto_suggest import AutoSuggestFromHistory, ThreadedAutoSuggest
@@ -55,7 +56,8 @@
 from prompt_toolkit.layout.processors import ConditionalProcessor, HighlightMatchingBracketProcessor
 from prompt_toolkit.lexers import PygmentsLexer
 from prompt_toolkit.output import ColorDepth
-from prompt_toolkit.shortcuts import CompleteStyle, PromptSession
+from prompt_toolkit.shortcuts import CompleteStyle, ProgressBar, PromptSession
+from prompt_toolkit.shortcuts.progress_bar import formatters as progress_bar_formatters
 import pymysql
 from pymysql.constants.CR import CR_SERVER_LOST
 from pymysql.constants.ER import ACCESS_DENIED_ERROR, HANDSHAKE_ERROR
@@ -2165,6 +2167,10 @@ class CliArgs:
         default=0.0,
         help='Pause in seconds between queries in batch mode.',
     )
+    progress: bool = clickdc.option(
+        is_flag=True,
+        help='Show progress with --batch.',
+    )
     use_keyring: str | None = clickdc.option(
         type=click.Choice(['true', 'false', 'reset']),
         default=None,
@@ -2709,17 +2715,70 @@ def dispatch_batch_statements(statements: str, batch_counter: int) -> None:
             click.secho(str(e), err=True, fg="red")
             sys.exit(1)
 
-    if cli_args.batch or not sys.stdin.isatty():
-        if cli_args.batch:
-            if not sys.stdin.isatty() and cli_args.batch != '-':
-                click.secho('Ignoring STDIN since --batch was also given.', err=True, fg='red')
-            try:
-                batch_h = click.open_file(cli_args.batch)
-            except (OSError, FileNotFoundError):
-                click.secho(f'Failed to open --batch file: {cli_args.batch}', err=True, fg='red')
-                sys.exit(1)
-        else:
-            batch_h = click.get_text_stream('stdin')
+    if cli_args.batch and cli_args.batch != '-' and cli_args.progress and sys.stderr.isatty():
+        # The actual number of SQL statements can be greater, if there is more than
+        # one statement per line, but this is how the  progress bar will count.
+        goal_statements = 0
+        if not sys.stdin.isatty() and cli_args.batch != '-':
+            click.secho('Ignoring STDIN since --batch was also given.', err=True, fg='yellow')
+        if os.path.exists(cli_args.batch) and not os.path.isfile(cli_args.batch):
+            click.secho('--progress is only compatible with a plain file.', err=True, fg='red')
+            sys.exit(1)
+        try:
+            batch_count_h = click.open_file(cli_args.batch)
+            for _statement, _counter in statements_from_filehandle(batch_count_h):
+                goal_statements += 1
+            batch_count_h.close()
+            batch_h = click.open_file(cli_args.batch)
+        except (OSError, FileNotFoundError):
+            click.secho(f'Failed to open --batch file: {cli_args.batch}', err=True, fg='red')
+            sys.exit(1)
+        except ValueError as e:
+            click.secho(f'Error reading --batch file: {cli_args.batch}: {e}', err=True, fg='red')
+            sys.exit(1)
+        try:
+            if goal_statements:
+                pb_style = prompt_toolkit.styles.Style.from_dict({'bar-a': 'reverse'})
+                custom_formatters = [
+                    progress_bar_formatters.Bar(start='[', end=']', sym_a=' ', sym_b=' ', sym_c=' '),
+                    progress_bar_formatters.Text(' '),
+                    progress_bar_formatters.Progress(),
+                    progress_bar_formatters.Text(' '),
+                    progress_bar_formatters.Text('eta ', style='class:time-left'),
+                    progress_bar_formatters.TimeLeft(),
+                    progress_bar_formatters.Text(' ', style='class:time-left'),
+                ]
+                err_output = prompt_toolkit.output.create_output(stdout=sys.stderr, always_prefer_tty=True)
+                with ProgressBar(style=pb_style, formatters=custom_formatters, output=err_output) as pb:
+                    for pb_counter in pb(range(goal_statements)):
+                        statement, _untrusted_counter = next(statements_from_filehandle(batch_h))
+                        dispatch_batch_statements(statement, pb_counter)
+        except (ValueError, StopIteration) as e:
+            click.secho(str(e), err=True, fg='red')
+            sys.exit(1)
+        finally:
+            batch_h.close()
+        sys.exit(0)
+
+    if cli_args.batch:
+        if not sys.stdin.isatty() and cli_args.batch != '-':
+            click.secho('Ignoring STDIN since --batch was also given.', err=True, fg='red')
+        try:
+            batch_h = click.open_file(cli_args.batch)
+        except (OSError, FileNotFoundError):
+            click.secho(f'Failed to open --batch file: {cli_args.batch}', err=True, fg='red')
+            sys.exit(1)
+        try:
+            for statement, counter in statements_from_filehandle(batch_h):
+                dispatch_batch_statements(statement, counter)
+            batch_h.close()
+        except ValueError as e:
+            click.secho(str(e), err=True, fg='red')
+            sys.exit(1)
+        sys.exit(0)
+
+    if not sys.stdin.isatty():
+        batch_h = click.get_text_stream('stdin')
         try:
             for statement, counter in statements_from_filehandle(batch_h):
                 dispatch_batch_statements(statement, counter)

test/pytests/test_main.py

@@ -6,8 +6,10 @@
 import io
 import os
 import shutil
+import sys
 from tempfile import NamedTemporaryFile
 from textwrap import dedent
+from types import SimpleNamespace
 
 import click
 from click.testing import CliRunner
@@ -1976,6 +1978,79 @@ def test_batch_file(monkeypatch):
         os.remove(batch_file.name)
 
 
+def test_batch_file_with_progress(monkeypatch):
+    mycli_main, MockMyCli = _noninteractive_mock_mycli(monkeypatch)
+    runner = CliRunner()
+
+    class DummyProgressBar:
+        calls = []
+
+        def __init__(self, *args, **kwargs):
+            pass
+
+        def __enter__(self):
+            return self
+
+        def __exit__(self, exc_type, exc, tb):
+            return False
+
+        def __call__(self, iterable):
+            values = list(iterable)
+            DummyProgressBar.calls.append(values)
+            return values
+
+    monkeypatch.setattr(mycli_main, 'ProgressBar', DummyProgressBar)
+    monkeypatch.setattr(mycli_main.prompt_toolkit.output, 'create_output', lambda **kwargs: object())
+    monkeypatch.setattr(
+        mycli_main,
+        'sys',
+        SimpleNamespace(
+            stdin=SimpleNamespace(isatty=lambda: False),
+            stderr=SimpleNamespace(isatty=lambda: True),
+            exit=sys.exit,
+        ),
+    )
+
+    with NamedTemporaryFile(prefix=TEMPFILE_PREFIX, mode='w', delete=False) as batch_file:
+        batch_file.write('select 2;\nselect 2;\nselect 2;\n')
+        batch_file.flush()
+
+    try:
+        result = runner.invoke(
+            mycli_main.click_entrypoint,
+            args=['--batch', batch_file.name, '--progress'],
+        )
+        assert result.exit_code == 0
+        assert MockMyCli.ran_queries == ['select 2;\n', 'select 2;\n', 'select 2;\n']
+        assert DummyProgressBar.calls == [[0, 1, 2]]
+    finally:
+        os.remove(batch_file.name)
+
+
+def test_batch_file_with_progress_requires_plain_file(monkeypatch, tmp_path):
+    mycli_main, MockMyCli = _noninteractive_mock_mycli(monkeypatch)
+    runner = CliRunner()
+
+    monkeypatch.setattr(
+        mycli_main,
+        'sys',
+        SimpleNamespace(
+            stdin=SimpleNamespace(isatty=lambda: False),
+            stderr=SimpleNamespace(isatty=lambda: True),
+            exit=sys.exit,
+        ),
+    )
+
+    result = runner.invoke(
+        mycli_main.click_entrypoint,
+        args=['--batch', str(tmp_path), '--progress'],
+    )
+
+    assert result.exit_code != 0
+    assert '--progress is only compatible with a plain file.' in result.output
+    assert MockMyCli.ran_queries == []
+
+
 def test_execute_arg_warns_about_ignoring_stdin(monkeypatch):
     mycli_main, MockMyCli = _noninteractive_mock_mycli(monkeypatch)
     runner = CliRunner()