_pre_process_line() - Code Metrics - Inspection of "Fix for properties backend which was rstripping va..." - ssato/python-anyconfig - Measure and Improve Code Quality continuously with Scrutinizer

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Pull Request — master (#50)

unknown

created 2016-09-26 09:06 UTC

_pre_process_line() B

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Lines	0
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Bugs	0	Features	0

Metric	Value
cc	5
c	1
b	0
f	0
dl	0
loc	27
rs	8.0894

#
# Copyright (C) 2012 - 2016 Satoru SATOH <ssato @ redhat.com>
# License: MIT
#
"""
Java properties file support.

.. versionchanged:: 0.6.99
   - Fix handling of empty values, pointed by @ajays20078

.. versionadded:: 0.2
   Added native Java properties parser instead of a plugin utilizes
   pyjavaproperties module.

- Format to support: Java Properties file, e.g.
  http://docs.oracle.com/javase/1.5.0/docs/api/java/util/Properties.html
- Requirements: None (built-in)
- Limitations:
  - Key and value separator of white spaces is not supported

- Special options: None
"""
from __future__ import absolute_import

import logging
import re

import anyconfig.backend.base
import anyconfig.compat


LOGGER = logging.getLogger(__name__)
_COMMENT_MARKERS = ("#", "!")


def _parseline(line):
    """
    Parse a line of Java properties file.

    :param line:
        A string to parse, must not start with ' ', '#' or '!' (comment)
    :return: A tuple of (key, value), both key and value may be None

    >>> _parseline(" ")
    (None, None)
    >>> _parseline("aaa:")
    ('aaa', '')
    >>> _parseline(" aaa:")
    ('aaa', '')
    >>> _parseline("calendar.japanese.type: LocalGregorianCalendar")
    ('calendar.japanese.type', 'LocalGregorianCalendar')

    FIXME:
    # >>> _parseline("aaa")
    # ('aaa', '')
    """
    matched = re.match(r"^(?:\s+)?(\S+)(?:\s+)?(?:(?<!\\)[:=])(?:\s+)?(.*)",
                       line)
    if not matched:
        LOGGER.warning("Invalid line found: %s", line)
        return (None, None)

    (key, val) = matched.groups()
    return (key, '' if val is None else val)


def _pre_process_line(line, comment_markers=_COMMENT_MARKERS):
    """
    Preprocess a line in properties; strip comments, etc.

    :param line:
        A string not starting w/ any white spaces and ending w/ line breaks.
        It may be empty. see also: :func:`load`.
    :param comment_markers: Comment markers, e.g. '#' (hash)

    >>> _pre_process_line('') is None
    True
    >>> s0 = "calendar.japanese.type: LocalGregorianCalendar"
    >>> _pre_process_line("# " + s0) is None
    True
    >>> _pre_process_line("! " + s0) is None
    True
    >>> _pre_process_line(s0 + "# comment")
    'calendar.japanese.type: LocalGregorianCalendar# comment'
    """
    if not line:
        return None

    if any(c in line for c in comment_markers):
        if line.startswith(comment_markers):
            return None

    return line


def unescape(in_s):
    """
    :param in_s: Input string
    """
    return re.sub(r"\\(.)", r"\1", in_s)


def _escape_char(in_c):
    """
    Escape some special characters in java .properties files.

    :param in_c: Input character

    >>> "\\:" == _escape_char(':')
    True
    >>> "\\=" == _escape_char('=')
    True
    >>> _escape_char('a')
    'a'
    """
    return '\\' + in_c if in_c in (':', '=', '\\') else in_c


def escape(in_s):
    """
    :param in_s: Input string
    """
    return ''.join(_escape_char(c) for c in in_s)


def load(stream, to_container=dict, comment_markers=_COMMENT_MARKERS):
    """
    Load and parse Java properties file given as a fiel or file-like object
    `stream`.

    :param stream: A file or file like object of Java properties files
    :param to_container:
        Factory function to create a dict-like object to store properties
    :param comment_markers: Comment markers, e.g. '#' (hash)
    :return: Dict-like object holding properties

    >>> to_strm = anyconfig.compat.StringIO
    >>> s0 = "calendar.japanese.type: LocalGregorianCalendar"
    >>> load(to_strm(''))
    {}
    >>> load(to_strm("# " + s0))
    {}
    >>> load(to_strm("! " + s0))
    {}
    >>> load(to_strm("calendar.japanese.type:"))
    {'calendar.japanese.type': ''}
    >>> load(to_strm(s0))
    {'calendar.japanese.type': 'LocalGregorianCalendar'}
    >>> load(to_strm(s0 + "# ..."))
    {'calendar.japanese.type': 'LocalGregorianCalendar# ...'}
    >>> s1 = r"key=a\\:b"
    >>> load(to_strm(s1))
    {'key': 'a:b'}
    >>> s2 = '''application/postscript: \\
    ...         x=Postscript File;y=.eps,.ps
    ... '''
    >>> load(to_strm(s2))
    {'application/postscript': 'x=Postscript File;y=.eps,.ps'}
    """
    ret = to_container()
    prev = ""

    for line in stream.readlines():
        line = _pre_process_line(prev + line.strip().rstrip(),
                                 comment_markers)
        # I don't think later case may happen but just in case.
        if line is None or not line:
            continue

        if line.endswith("\\"):
            prev += line.rstrip(" \\")
            continue

        prev = ""  # re-initialize for later use.

        (key, val) = _parseline(line)
        if key is None:
            LOGGER.warning("Failed to parse the line: %s", line)
            continue

        ret[key] = unescape(val)

    return ret


class Parser(anyconfig.backend.base.FromStreamLoader,
             anyconfig.backend.base.ToStreamDumper):
    """
    Parser for Java properties files.
    """
    _type = "properties"
    _extensions = ["properties"]

    def load_from_stream(self, stream, to_container, **kwargs):
        """
        Load config from given file like object `stream`.

        :param stream: A file or file like object of Java properties files
        :param to_container: callble to make a container object
        :param kwargs: optional keyword parameters (ignored)

        :return: Dict-like object holding config parameters
        """
        return load(stream, to_container=to_container)

    def dump_to_stream(self, cnf, stream, **kwargs):
        """
        Dump config `cnf` to a file or file-like object `stream`.

        :param cnf: Java properties config data to dump
        :param stream: Java properties file or file like object
        :param kwargs: backend-specific optional keyword parameters :: dict
        """
        for key, val in anyconfig.compat.iteritems(cnf):
            stream.write("%s = %s\n" % (key, escape(val)))

# vim:sw=4:ts=4:et:


1			#
2			# Copyright (C) 2012 - 2016 Satoru SATOH <ssato @ redhat.com>
3			# License: MIT
4			#
5			"""
6			Java properties file support.
7
8			.. versionchanged:: 0.6.99
9			- Fix handling of empty values, pointed by @ajays20078
10
11			.. versionadded:: 0.2
12			Added native Java properties parser instead of a plugin utilizes
13			pyjavaproperties module.
14
15			- Format to support: Java Properties file, e.g.
16			http://docs.oracle.com/javase/1.5.0/docs/api/java/util/Properties.html
17			- Requirements: None (built-in)
18			- Limitations:
19			- Key and value separator of white spaces is not supported
20
21			- Special options: None
22			"""
23			from __future__ import absolute_import
24
25			import logging
26			import re
27
28			import anyconfig.backend.base
29			import anyconfig.compat
30
31
32			LOGGER = logging.getLogger(__name__)
33			_COMMENT_MARKERS = ("#", "!")
34
35
36			def _parseline(line):
37			"""
38			Parse a line of Java properties file.
39
40			:param line:
41			A string to parse, must not start with ' ', '#' or '!' (comment)
42			:return: A tuple of (key, value), both key and value may be None
43
44			>>> _parseline(" ")
45			(None, None)
46			>>> _parseline("aaa:")
47			('aaa', '')
48			>>> _parseline(" aaa:")
49			('aaa', '')
50			>>> _parseline("calendar.japanese.type: LocalGregorianCalendar")
51			('calendar.japanese.type', 'LocalGregorianCalendar')
52
53			FIXME:
54			# >>> _parseline("aaa")
55			# ('aaa', '')
56			"""
57			matched = re.match(r"^(?:\s+)?(\S+)(?:\s+)?(?:(?<!\\)[:=])(?:\s+)?(.*)",
58			line)
59			if not matched:
60			LOGGER.warning("Invalid line found: %s", line)
61			return (None, None)
62
63			(key, val) = matched.groups()
64			return (key, '' if val is None else val)
65
66
67			def _pre_process_line(line, comment_markers=_COMMENT_MARKERS):
68			"""
69			Preprocess a line in properties; strip comments, etc.
70
71			:param line:
72			A string not starting w/ any white spaces and ending w/ line breaks.
73			It may be empty. see also: :func:`load`.
74			:param comment_markers: Comment markers, e.g. '#' (hash)
75
76			>>> _pre_process_line('') is None
77			True
78			>>> s0 = "calendar.japanese.type: LocalGregorianCalendar"
79			>>> _pre_process_line("# " + s0) is None
80			True
81			>>> _pre_process_line("! " + s0) is None
82			True
83			>>> _pre_process_line(s0 + "# comment")
84			'calendar.japanese.type: LocalGregorianCalendar# comment'
85			"""
86			if not line:
87			return None
88
89			if any(c in line for c in comment_markers):
90			if line.startswith(comment_markers):
91			return None
92
93			return line
94
95
96			def unescape(in_s):
97			"""
98			:param in_s: Input string
99			"""
100			return re.sub(r"\\(.)", r"\1", in_s)
101
102
103			def _escape_char(in_c):
104			"""
105			Escape some special characters in java .properties files.
106
107			:param in_c: Input character
108
109			>>> "\\:" == _escape_char(':')
110			True
111			>>> "\\=" == _escape_char('=')
112			True
113			>>> _escape_char('a')
114			'a'
115			"""
116			return '\\' + in_c if in_c in (':', '=', '\\') else in_c
117
118
119			def escape(in_s):
120			"""
121			:param in_s: Input string
122			"""
123			return ''.join(_escape_char(c) for c in in_s)
124
125
126			def load(stream, to_container=dict, comment_markers=_COMMENT_MARKERS):
127			"""
128			Load and parse Java properties file given as a fiel or file-like object
129			`stream`.
130
131			:param stream: A file or file like object of Java properties files
132			:param to_container:
133			Factory function to create a dict-like object to store properties
134			:param comment_markers: Comment markers, e.g. '#' (hash)
135			:return: Dict-like object holding properties
136
137			>>> to_strm = anyconfig.compat.StringIO
138			>>> s0 = "calendar.japanese.type: LocalGregorianCalendar"
139			>>> load(to_strm(''))
140			{}
141			>>> load(to_strm("# " + s0))
142			{}
143			>>> load(to_strm("! " + s0))
144			{}
145			>>> load(to_strm("calendar.japanese.type:"))
146			{'calendar.japanese.type': ''}
147			>>> load(to_strm(s0))
148			{'calendar.japanese.type': 'LocalGregorianCalendar'}
149			>>> load(to_strm(s0 + "# ..."))
150			{'calendar.japanese.type': 'LocalGregorianCalendar# ...'}
151			>>> s1 = r"key=a\\:b"
152			>>> load(to_strm(s1))
153			{'key': 'a:b'}
154			>>> s2 = '''application/postscript: \\
155			... x=Postscript File;y=.eps,.ps
156			... '''
157			>>> load(to_strm(s2))
158			{'application/postscript': 'x=Postscript File;y=.eps,.ps'}
159			"""
160			ret = to_container()
161			prev = ""
162
163			for line in stream.readlines():
164			line = _pre_process_line(prev + line.strip().rstrip(),
165			comment_markers)
166			# I don't think later case may happen but just in case.
167			if line is None or not line:
168			continue
169
170			if line.endswith("\\"):
171			prev += line.rstrip(" \\")
172			continue
173
174			prev = "" # re-initialize for later use.
175
176			(key, val) = _parseline(line)
177			if key is None:
178			LOGGER.warning("Failed to parse the line: %s", line)
179			continue
180
181			ret[key] = unescape(val)
182
183			return ret
184
185
186			class Parser(anyconfig.backend.base.FromStreamLoader,
187			anyconfig.backend.base.ToStreamDumper):
188			"""
189			Parser for Java properties files.
190			"""
191			_type = "properties"
192			_extensions = ["properties"]
193
194			def load_from_stream(self, stream, to_container, **kwargs):
195			"""
196			Load config from given file like object `stream`.
197
198			:param stream: A file or file like object of Java properties files
199			:param to_container: callble to make a container object
200			:param kwargs: optional keyword parameters (ignored)
201
202			:return: Dict-like object holding config parameters
203			"""
204			return load(stream, to_container=to_container)
205
206			def dump_to_stream(self, cnf, stream, **kwargs):
207			"""
208			Dump config `cnf` to a file or file-like object `stream`.
209
210			:param cnf: Java properties config data to dump
211			:param stream: Java properties file or file like object
212			:param kwargs: backend-specific optional keyword parameters :: dict
213			"""
214			for key, val in anyconfig.compat.iteritems(cnf):
215			stream.write("%s = %s\n" % (key, escape(val)))
216
217			# vim:sw=4:ts=4:et:
218

ssato / python-anyconfig

Pull Request — master (#50)

_pre_process_line() B

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