diff options
Diffstat (limited to 'cliff/lister.py')
| -rw-r--r-- | cliff/lister.py | 34 |
1 files changed, 33 insertions, 1 deletions
diff --git a/cliff/lister.py b/cliff/lister.py index a4ec7c3..24e3127 100644 --- a/cliff/lister.py +++ b/cliff/lister.py @@ -1,6 +1,7 @@ """Application base class for providing a list of data as output. """ import abc +import itertools import logging from .display import DisplayCommandBase @@ -28,8 +29,39 @@ class Lister(DisplayCommandBase): containing the data to be listed. """ + def get_parser(self, prog_name): + parser = super(Lister, self).get_parser(prog_name) + parser.add_argument( + '-c', '--column', + action='append', + default=[], + dest='columns', + metavar='COLUMN', + help='specify the column(s) to include, can be repeated', + ) + return parser + def run(self, parsed_args): column_names, data = self.get_data(parsed_args) + if not parsed_args.columns: + columns_to_include = column_names + data_gen = data + else: + columns_to_include = [c for c in column_names + if c in parsed_args.columns + ] + if not columns_to_include: + raise ValueError('No recognized column names in %s' % + str(parsed_args.columns)) + # Set up argument to compress() + selector = [(c in columns_to_include) + for c in column_names] + # Generator expression to only return the parts of a row + # of data that the user has expressed interest in + # seeing. We have to convert the compress() output to a + # list so the table formatter can ask for its length. + data_gen = (list(itertools.compress(row, selector)) + for row in data) formatter = self.formatters[parsed_args.formatter] - formatter.emit_list(column_names, data, self.app.stdout, parsed_args) + formatter.emit_list(columns_to_include, data_gen, self.app.stdout, parsed_args) return 0 |