re-re-factor progress bar!

.pre-commit-config.yaml

@@ -38,7 +38,8 @@ repos:
             (?x)^(
                 aiida/engine/processes/calcjobs/calcjob.py|
                 aiida/tools/groups/paths.py|
-                aiida/tools/importexport/dbexport/__init__.py
+                aiida/tools/importexport/dbexport/__init__.py|
+                aiida/tools/importexport/common/progress_reporter.py|
             )$
 
 -   repo: local

aiida/cmdline/commands/cmd_export.py

@@ -9,7 +9,7 @@
 ###########################################################################
 # pylint: disable=too-many-arguments,import-error,too-many-locals
 """`verdi export` command."""
-
+from functools import partial
 import os
 import tempfile
 
@@ -95,8 +95,11 @@ def create(
     their provenance, according to the rules outlined in the documentation.
     You can modify some of those rules using options of this command.
     """
+    from tqdm import tqdm
+    from aiida.common.progress_reporter import set_progress_reporter
     from aiida.tools.importexport import export, ExportFileFormat
     from aiida.tools.importexport.common.exceptions import ArchiveExportError
+    from aiida.tools.importexport.common.config import BAR_FORMAT
 
     entities = []
 
@@ -133,8 +136,10 @@ def create(
     elif archive_format == 'tar.gz':
         export_format = ExportFileFormat.TAR_GZIPPED
 
+    set_progress_reporter(partial(tqdm, bar_format=BAR_FORMAT, leave=verbose))
+
     try:
-        export(entities, filename=output_file, file_format=export_format, verbose=verbose, **kwargs)
+        export(entities, filename=output_file, file_format=export_format, **kwargs)
     except ArchiveExportError as exception:
         echo.echo_critical(f'failed to write the archive file. Exception: {exception}')
     else:

aiida/common/__init__.py

@@ -20,5 +20,9 @@
 from .extendeddicts import *
 from .links import *
 from .log import *
+from .progress_reporter import *
 
-__all__ = (datastructures.__all__ + exceptions.__all__ + extendeddicts.__all__ + links.__all__ + log.__all__)
+__all__ = (
+    datastructures.__all__ + exceptions.__all__ + extendeddicts.__all__ + links.__all__ + log.__all__ +
+    progress_reporter.__all__
+)

aiida/common/progress_reporter.py

@@ -0,0 +1,103 @@
+# -*- coding: utf-8 -*-
+###########################################################################
+# Copyright (c), The AiiDA team. All rights reserved.                     #
+# This file is part of the AiiDA code.                                    #
+#                                                                         #
+# The code is hosted on GitHub at https://github.com/aiidateam/aiida-core #
+# For further information on the license, see the LICENSE.txt file        #
+# For further information please visit http://www.aiida.net               #
+###########################################################################
+# pylint: disable=global-statement,unused-argument
+"""Provide a singleton progress reporter implementation.
+
+The interface is inspired by `tqdm <https://github.com/tqdm/tqdm>`,
+and indeed a valid implementation is::
+
+    from tqdm import tqdm
+    set_progress_reporter(tqdm)
+
+"""
+from contextlib import contextmanager
+from typing import Any, Callable, ContextManager, Iterator, Optional
+
+__all__ = ('get_progress_reporter', 'set_progress_reporter', 'progress_reporter_base', 'ProgressIncrementerBase')
+
+
+class ProgressIncrementerBase:
+    """A base class for incrementing a progress reporter."""
+
+    def set_description_str(self, text: Optional[str] = None, refresh: bool = True):
+        """Set the text shown by the progress reporter.
+
+        :param text: The text to show
+        :param refresh: Force refresh of the progress reporter
+
+        """
+
+    def update(self, n: int = 1):  # pylint: disable=invalid-name
+        """Update the progress counter.
+
+        :param n: Increment to add to the internal counter of iterations
+
+        """
+
+
+@contextmanager
+def progress_reporter_base(*,
+                           total: int,
+                           desc: Optional[str] = None,
+                           **kwargs: Any) -> Iterator[ProgressIncrementerBase]:
+    """A context manager for providing a progress reporter for a process.
+
+    Example Usage::
+
+        with progress_reporter(total=10, desc="A process:") as progress:
+            for i in range(10):
+                progress.set_description_str(f"A process: {i}")
+                progress.update()
+
+    :param total: The number of expected iterations.
+    :param desc: A description of the process
+    :yield: A class for incrementing the progress reporter
+
+    """
+    yield ProgressIncrementerBase()
+
+
+PROGRESS_REPORTER = progress_reporter_base
+
+
+def get_progress_reporter() -> Callable[..., ContextManager[Any]]:
+    """Return the progress reporter
+
+    Example Usage::
+
+        with get_progress_reporter()(total=10, desc="A process:") as progress:
+            for i in range(10):
+                progress.set_description_str(f"A process: {i}")
+                progress.update()
+
+    """
+    global PROGRESS_REPORTER
+    return PROGRESS_REPORTER  # type: ignore
+
+
+def set_progress_reporter(reporter: Optional[Callable[..., ContextManager[Any]]] = None):
+    """Set the progress reporter implementation
+
+    :param reporter: A context manager for providing a progress reporter for a process.
+        If None, reset to default null reporter
+
+    The reporter should be a context manager that implements the
+    :func:`~aiida.common.progress_reporter.progress_reporter_base` interface.
+
+    Example Usage::
+
+        with get_progress_reporter()(total=10, desc="A process:") as progress:
+            for i in range(10):
+                progress.set_description_str(f"A process: {i}")
+                progress.update()
+
+    """
+    global PROGRESS_REPORTER
+    PROGRESS_REPORTER = reporter or progress_reporter_base  # type: ignore