python getchar功能_Python click 模块，getchar() 实例源码 - 编程字典
def view(visualization_path, index_extension):
# Guard headless envs from having to import anything large
import sys
if not os.getenv("DISPLAY") and sys.platform != "darwin":
raise click.UsageError(
'Visualization viewing is currently not supported in headless '
'environments. You can view Visualizations (and Artifacts) at '
'https://view.qiime2.org, or move the Visualization to an '
'environment with a display and view it with `qiime tools view`.')
import zipfile
import qiime2.sdk
if index_extension.startswith('.'):
index_extension = index_extension[1:]
try:
visualization = qiime2.sdk.Visualization.load(visualization_path)
# TODO: currently a KeyError is raised if a zipped file that is not a
# QIIME 2 result is passed. This should be handled better by the framework.
except (zipfile.BadZipFile, KeyError, TypeError):
raise click.BadParameter(
'%sis not a QIIME 2 Visualization. Only QIIME 2 Visualizations '
'can be viewed.' % visualization_path)
index_paths = visualization.get_index_paths(relative=False)
if index_extension not in index_paths:
raise click.BadParameter(
'No index%sfile with is present in the archive. Available index '
'extensions are:%s' % (index_extension,
', '.join(index_paths.keys())))
else:
index_path = index_paths[index_extension]
launch_status = click.launch(index_path)
if launch_status != 0:
click.echo('Viewing visualization failed while attempting to '
'open%s' % index_path, err=True)
else:
while True:
click.echo(
"Press the 'q' key, Control-C, or Control-D to quit. This "
"view may no longer be accessible or work correctly after "
"quitting.", nl=False)
# There is currently a bug in click.getchar where translation
# of Control-C and Control-D into KeyboardInterrupt and
# EOFError (respectively) does not work on Python 3. The code
# here should continue to work as expected when the bug is
# fixed in Click.
#
# https://github.com/pallets/click/issues/583
try:
char = click.getchar()
click.echo()
if char in {'q', '\x03', '\x04'}:
break
except (KeyboardInterrupt, EOFError):
break