| """Pythonic command-line interface parser that will make you smile. |
| |
| * http://docopt.org |
| * Repository and issue-tracker: https://github.com/docopt/docopt |
| * Licensed under terms of MIT license (see LICENSE-MIT) |
| * Copyright (c) 2013 Vladimir Keleshev, vladimir@keleshev.com |
| |
| """ |
| import sys |
| import re |
| |
| |
| __all__ = ['docopt'] |
| __version__ = '0.6.1' |
| |
| |
| class DocoptLanguageError(Exception): |
| |
| """Error in construction of usage-message by developer.""" |
| |
| |
| class DocoptExit(SystemExit): |
| |
| """Exit in case user invoked program with incorrect arguments.""" |
| |
| usage = '' |
| |
| def __init__(self, message=''): |
| SystemExit.__init__(self, (message + '\n' + self.usage).strip()) |
| |
| |
| class Pattern(object): |
| |
| def __eq__(self, other): |
| return repr(self) == repr(other) |
| |
| def __hash__(self): |
| return hash(repr(self)) |
| |
| def fix(self): |
| self.fix_identities() |
| self.fix_repeating_arguments() |
| return self |
| |
| def fix_identities(self, uniq=None): |
| """Make pattern-tree tips point to same object if they are equal.""" |
| if not hasattr(self, 'children'): |
| return self |
| uniq = list(set(self.flat())) if uniq is None else uniq |
| for i, child in enumerate(self.children): |
| if not hasattr(child, 'children'): |
| assert child in uniq |
| self.children[i] = uniq[uniq.index(child)] |
| else: |
| child.fix_identities(uniq) |
| |
| def fix_repeating_arguments(self): |
| """Fix elements that should accumulate/increment values.""" |
| either = [list(child.children) for child in transform(self).children] |
| for case in either: |
| for e in [child for child in case if case.count(child) > 1]: |
| if type(e) is Argument or type(e) is Option and e.argcount: |
| if e.value is None: |
| e.value = [] |
| elif type(e.value) is not list: |
| e.value = e.value.split() |
| if type(e) is Command or type(e) is Option and e.argcount == 0: |
| e.value = 0 |
| return self |
| |
| |
| def transform(pattern): |
| """Expand pattern into an (almost) equivalent one, but with single Either. |
| |
| Example: ((-a | -b) (-c | -d)) => (-a -c | -a -d | -b -c | -b -d) |
| Quirks: [-a] => (-a), (-a...) => (-a -a) |
| |
| """ |
| result = [] |
| groups = [[pattern]] |
| while groups: |
| children = groups.pop(0) |
| parents = [Required, Optional, OptionsShortcut, Either, OneOrMore] |
| if any(t in map(type, children) for t in parents): |
| child = [c for c in children if type(c) in parents][0] |
| children.remove(child) |
| if type(child) is Either: |
| for c in child.children: |
| groups.append([c] + children) |
| elif type(child) is OneOrMore: |
| groups.append(child.children * 2 + children) |
| else: |
| groups.append(child.children + children) |
| else: |
| result.append(children) |
| return Either(*[Required(*e) for e in result]) |
| |
| |
| class LeafPattern(Pattern): |
| |
| """Leaf/terminal node of a pattern tree.""" |
| |
| def __init__(self, name, value=None): |
| self.name, self.value = name, value |
| |
| def __repr__(self): |
| return '%s(%r, %r)' % (self.__class__.__name__, self.name, self.value) |
| |
| def flat(self, *types): |
| return [self] if not types or type(self) in types else [] |
| |
| def match(self, left, collected=None): |
| collected = [] if collected is None else collected |
| pos, match = self.single_match(left) |
| if match is None: |
| return False, left, collected |
| left_ = left[:pos] + left[pos + 1:] |
| same_name = [a for a in collected if a.name == self.name] |
| if type(self.value) in (int, list): |
| if type(self.value) is int: |
| increment = 1 |
| else: |
| increment = ([match.value] if type(match.value) is str |
| else match.value) |
| if not same_name: |
| match.value = increment |
| return True, left_, collected + [match] |
| same_name[0].value += increment |
| return True, left_, collected |
| return True, left_, collected + [match] |
| |
| |
| class BranchPattern(Pattern): |
| |
| """Branch/inner node of a pattern tree.""" |
| |
| def __init__(self, *children): |
| self.children = list(children) |
| |
| def __repr__(self): |
| return '%s(%s)' % (self.__class__.__name__, |
| ', '.join(repr(a) for a in self.children)) |
| |
| def flat(self, *types): |
| if type(self) in types: |
| return [self] |
| return sum([child.flat(*types) for child in self.children], []) |
| |
| |
| class Argument(LeafPattern): |
| |
| def single_match(self, left): |
| for n, pattern in enumerate(left): |
| if type(pattern) is Argument: |
| return n, Argument(self.name, pattern.value) |
| return None, None |
| |
| @classmethod |
| def parse(class_, source): |
| name = re.findall('(<\S*?>)', source)[0] |
| value = re.findall('\[default: (.*)\]', source, flags=re.I) |
| return class_(name, value[0] if value else None) |
| |
| |
| class Command(Argument): |
| |
| def __init__(self, name, value=False): |
| self.name, self.value = name, value |
| |
| def single_match(self, left): |
| for n, pattern in enumerate(left): |
| if type(pattern) is Argument: |
| if pattern.value == self.name: |
| return n, Command(self.name, True) |
| else: |
| break |
| return None, None |
| |
| |
| class Option(LeafPattern): |
| |
| def __init__(self, short=None, long=None, argcount=0, value=False): |
| assert argcount in (0, 1) |
| self.short, self.long, self.argcount = short, long, argcount |
| self.value = None if value is False and argcount else value |
| |
| @classmethod |
| def parse(class_, option_description): |
| short, long, argcount, value = None, None, 0, False |
| options, _, description = option_description.strip().partition(' ') |
| options = options.replace(',', ' ').replace('=', ' ') |
| for s in options.split(): |
| if s.startswith('--'): |
| long = s |
| elif s.startswith('-'): |
| short = s |
| else: |
| argcount = 1 |
| if argcount: |
| matched = re.findall('\[default: (.*)\]', description, flags=re.I) |
| value = matched[0] if matched else None |
| return class_(short, long, argcount, value) |
| |
| def single_match(self, left): |
| for n, pattern in enumerate(left): |
| if self.name == pattern.name: |
| return n, pattern |
| return None, None |
| |
| @property |
| def name(self): |
| return self.long or self.short |
| |
| def __repr__(self): |
| return 'Option(%r, %r, %r, %r)' % (self.short, self.long, |
| self.argcount, self.value) |
| |
| |
| class Required(BranchPattern): |
| |
| def match(self, left, collected=None): |
| collected = [] if collected is None else collected |
| l = left |
| c = collected |
| for pattern in self.children: |
| matched, l, c = pattern.match(l, c) |
| if not matched: |
| return False, left, collected |
| return True, l, c |
| |
| |
| class Optional(BranchPattern): |
| |
| def match(self, left, collected=None): |
| collected = [] if collected is None else collected |
| for pattern in self.children: |
| m, left, collected = pattern.match(left, collected) |
| return True, left, collected |
| |
| |
| class OptionsShortcut(Optional): |
| |
| """Marker/placeholder for [options] shortcut.""" |
| |
| |
| class OneOrMore(BranchPattern): |
| |
| def match(self, left, collected=None): |
| assert len(self.children) == 1 |
| collected = [] if collected is None else collected |
| l = left |
| c = collected |
| l_ = None |
| matched = True |
| times = 0 |
| while matched: |
| # could it be that something didn't match but changed l or c? |
| matched, l, c = self.children[0].match(l, c) |
| times += 1 if matched else 0 |
| if l_ == l: |
| break |
| l_ = l |
| if times >= 1: |
| return True, l, c |
| return False, left, collected |
| |
| |
| class Either(BranchPattern): |
| |
| def match(self, left, collected=None): |
| collected = [] if collected is None else collected |
| outcomes = [] |
| for pattern in self.children: |
| matched, _, _ = outcome = pattern.match(left, collected) |
| if matched: |
| outcomes.append(outcome) |
| if outcomes: |
| return min(outcomes, key=lambda outcome: len(outcome[1])) |
| return False, left, collected |
| |
| |
| class Tokens(list): |
| |
| def __init__(self, source, error=DocoptExit): |
| self += source.split() if hasattr(source, 'split') else source |
| self.error = error |
| |
| @staticmethod |
| def from_pattern(source): |
| source = re.sub(r'([\[\]\(\)\|]|\.\.\.)', r' \1 ', source) |
| source = [s for s in re.split('\s+|(\S*<.*?>)', source) if s] |
| return Tokens(source, error=DocoptLanguageError) |
| |
| def move(self): |
| return self.pop(0) if len(self) else None |
| |
| def current(self): |
| return self[0] if len(self) else None |
| |
| |
| def parse_long(tokens, options): |
| """long ::= '--' chars [ ( ' ' | '=' ) chars ] ;""" |
| long, eq, value = tokens.move().partition('=') |
| assert long.startswith('--') |
| value = None if eq == value == '' else value |
| similar = [o for o in options if o.long == long] |
| if tokens.error is DocoptExit and similar == []: # if no exact match |
| similar = [o for o in options if o.long and o.long.startswith(long)] |
| if len(similar) > 1: # might be simply specified ambiguously 2+ times? |
| raise tokens.error('%s is not a unique prefix: %s?' % |
| (long, ', '.join(o.long for o in similar))) |
| elif len(similar) < 1: |
| argcount = 1 if eq == '=' else 0 |
| o = Option(None, long, argcount) |
| options.append(o) |
| if tokens.error is DocoptExit: |
| o = Option(None, long, argcount, value if argcount else True) |
| else: |
| o = Option(similar[0].short, similar[0].long, |
| similar[0].argcount, similar[0].value) |
| if o.argcount == 0: |
| if value is not None: |
| raise tokens.error('%s must not have an argument' % o.long) |
| else: |
| if value is None: |
| if tokens.current() in [None, '--']: |
| raise tokens.error('%s requires argument' % o.long) |
| value = tokens.move() |
| if tokens.error is DocoptExit: |
| o.value = value if value is not None else True |
| return [o] |
| |
| |
| def parse_shorts(tokens, options): |
| """shorts ::= '-' ( chars )* [ [ ' ' ] chars ] ;""" |
| token = tokens.move() |
| assert token.startswith('-') and not token.startswith('--') |
| left = token.lstrip('-') |
| parsed = [] |
| while left != '': |
| short, left = '-' + left[0], left[1:] |
| similar = [o for o in options if o.short == short] |
| if len(similar) > 1: |
| raise tokens.error('%s is specified ambiguously %d times' % |
| (short, len(similar))) |
| elif len(similar) < 1: |
| o = Option(short, None, 0) |
| options.append(o) |
| if tokens.error is DocoptExit: |
| o = Option(short, None, 0, True) |
| else: # why copying is necessary here? |
| o = Option(short, similar[0].long, |
| similar[0].argcount, similar[0].value) |
| value = None |
| if o.argcount != 0: |
| if left == '': |
| if tokens.current() in [None, '--']: |
| raise tokens.error('%s requires argument' % short) |
| value = tokens.move() |
| else: |
| value = left |
| left = '' |
| if tokens.error is DocoptExit: |
| o.value = value if value is not None else True |
| parsed.append(o) |
| return parsed |
| |
| |
| def parse_pattern(source, options): |
| tokens = Tokens.from_pattern(source) |
| result = parse_expr(tokens, options) |
| if tokens.current() is not None: |
| raise tokens.error('unexpected ending: %r' % ' '.join(tokens)) |
| return Required(*result) |
| |
| |
| def parse_expr(tokens, options): |
| """expr ::= seq ( '|' seq )* ;""" |
| seq = parse_seq(tokens, options) |
| if tokens.current() != '|': |
| return seq |
| result = [Required(*seq)] if len(seq) > 1 else seq |
| while tokens.current() == '|': |
| tokens.move() |
| seq = parse_seq(tokens, options) |
| result += [Required(*seq)] if len(seq) > 1 else seq |
| return [Either(*result)] if len(result) > 1 else result |
| |
| |
| def parse_seq(tokens, options): |
| """seq ::= ( atom [ '...' ] )* ;""" |
| result = [] |
| while tokens.current() not in [None, ']', ')', '|']: |
| atom = parse_atom(tokens, options) |
| if tokens.current() == '...': |
| atom = [OneOrMore(*atom)] |
| tokens.move() |
| result += atom |
| return result |
| |
| |
| def parse_atom(tokens, options): |
| """atom ::= '(' expr ')' | '[' expr ']' | 'options' |
| | long | shorts | argument | command ; |
| """ |
| token = tokens.current() |
| result = [] |
| if token in '([': |
| tokens.move() |
| matching, pattern = {'(': [')', Required], '[': [']', Optional]}[token] |
| result = pattern(*parse_expr(tokens, options)) |
| if tokens.move() != matching: |
| raise tokens.error("unmatched '%s'" % token) |
| return [result] |
| elif token == 'options': |
| tokens.move() |
| return [OptionsShortcut()] |
| elif token.startswith('--') and token != '--': |
| return parse_long(tokens, options) |
| elif token.startswith('-') and token not in ('-', '--'): |
| return parse_shorts(tokens, options) |
| elif token.startswith('<') and token.endswith('>') or token.isupper(): |
| return [Argument(tokens.move())] |
| else: |
| return [Command(tokens.move())] |
| |
| |
| def parse_argv(tokens, options, options_first=False): |
| """Parse command-line argument vector. |
| |
| If options_first: |
| argv ::= [ long | shorts ]* [ argument ]* [ '--' [ argument ]* ] ; |
| else: |
| argv ::= [ long | shorts | argument ]* [ '--' [ argument ]* ] ; |
| |
| """ |
| parsed = [] |
| while tokens.current() is not None: |
| if tokens.current() == '--': |
| return parsed + [Argument(None, v) for v in tokens] |
| elif tokens.current().startswith('--'): |
| parsed += parse_long(tokens, options) |
| elif tokens.current().startswith('-') and tokens.current() != '-': |
| parsed += parse_shorts(tokens, options) |
| elif options_first: |
| return parsed + [Argument(None, v) for v in tokens] |
| else: |
| parsed.append(Argument(None, tokens.move())) |
| return parsed |
| |
| |
| def parse_defaults(doc): |
| defaults = [] |
| for s in parse_section('options:', doc): |
| # FIXME corner case "bla: options: --foo" |
| _, _, s = s.partition(':') # get rid of "options:" |
| split = re.split('\n[ \t]*(-\S+?)', '\n' + s)[1:] |
| split = [s1 + s2 for s1, s2 in zip(split[::2], split[1::2])] |
| options = [Option.parse(s) for s in split if s.startswith('-')] |
| defaults += options |
| return defaults |
| |
| |
| def parse_section(name, source): |
| pattern = re.compile('^([^\n]*' + name + '[^\n]*\n?(?:[ \t].*?(?:\n|$))*)', |
| re.IGNORECASE | re.MULTILINE) |
| return [s.strip() for s in pattern.findall(source)] |
| |
| |
| def formal_usage(section): |
| _, _, section = section.partition(':') # drop "usage:" |
| pu = section.split() |
| return '( ' + ' '.join(') | (' if s == pu[0] else s for s in pu[1:]) + ' )' |
| |
| |
| def extras(help, version, options, doc): |
| if help and any((o.name in ('-h', '--help')) and o.value for o in options): |
| print(doc.strip("\n")) |
| sys.exit() |
| if version and any(o.name == '--version' and o.value for o in options): |
| print(version) |
| sys.exit() |
| |
| |
| class Dict(dict): |
| def __repr__(self): |
| return '{%s}' % ',\n '.join('%r: %r' % i for i in sorted(self.items())) |
| |
| |
| def docopt(doc, argv=None, help=True, version=None, options_first=False): |
| """Parse `argv` based on command-line interface described in `doc`. |
| |
| `docopt` creates your command-line interface based on its |
| description that you pass as `doc`. Such description can contain |
| --options, <positional-argument>, commands, which could be |
| [optional], (required), (mutually | exclusive) or repeated... |
| |
| Parameters |
| ---------- |
| doc : str |
| Description of your command-line interface. |
| argv : list of str, optional |
| Argument vector to be parsed. sys.argv[1:] is used if not |
| provided. |
| help : bool (default: True) |
| Set to False to disable automatic help on -h or --help |
| options. |
| version : any object |
| If passed, the object will be printed if --version is in |
| `argv`. |
| options_first : bool (default: False) |
| Set to True to require options precede positional arguments, |
| i.e. to forbid options and positional arguments intermix. |
| |
| Returns |
| ------- |
| args : dict |
| A dictionary, where keys are names of command-line elements |
| such as e.g. "--verbose" and "<path>", and values are the |
| parsed values of those elements. |
| |
| Example |
| ------- |
| >>> from docopt import docopt |
| >>> doc = ''' |
| ... Usage: |
| ... my_program tcp <host> <port> [--timeout=<seconds>] |
| ... my_program serial <port> [--baud=<n>] [--timeout=<seconds>] |
| ... my_program (-h | --help | --version) |
| ... |
| ... Options: |
| ... -h, --help Show this screen and exit. |
| ... --baud=<n> Baudrate [default: 9600] |
| ... ''' |
| >>> argv = ['tcp', '127.0.0.1', '80', '--timeout', '30'] |
| >>> docopt(doc, argv) |
| {'--baud': '9600', |
| '--help': False, |
| '--timeout': '30', |
| '--version': False, |
| '<host>': '127.0.0.1', |
| '<port>': '80', |
| 'serial': False, |
| 'tcp': True} |
| |
| See also |
| -------- |
| * For video introduction see http://docopt.org |
| * Full documentation is available in README.rst as well as online |
| at https://github.com/docopt/docopt#readme |
| |
| """ |
| argv = sys.argv[1:] if argv is None else argv |
| |
| usage_sections = parse_section('usage:', doc) |
| if len(usage_sections) == 0: |
| raise DocoptLanguageError('"usage:" (case-insensitive) not found.') |
| if len(usage_sections) > 1: |
| raise DocoptLanguageError('More than one "usage:" (case-insensitive).') |
| DocoptExit.usage = usage_sections[0] |
| |
| options = parse_defaults(doc) |
| pattern = parse_pattern(formal_usage(DocoptExit.usage), options) |
| # [default] syntax for argument is disabled |
| #for a in pattern.flat(Argument): |
| # same_name = [d for d in arguments if d.name == a.name] |
| # if same_name: |
| # a.value = same_name[0].value |
| argv = parse_argv(Tokens(argv), list(options), options_first) |
| pattern_options = set(pattern.flat(Option)) |
| for options_shortcut in pattern.flat(OptionsShortcut): |
| doc_options = parse_defaults(doc) |
| options_shortcut.children = list(set(doc_options) - pattern_options) |
| #if any_options: |
| # options_shortcut.children += [Option(o.short, o.long, o.argcount) |
| # for o in argv if type(o) is Option] |
| extras(help, version, argv, doc) |
| matched, left, collected = pattern.fix().match(argv) |
| if matched and left == []: # better error message if left? |
| return Dict((a.name, a.value) for a in (pattern.flat() + collected)) |
| raise DocoptExit() |
