# (c) 2005 Ian Bicking and contributors; written for Paste (http://pythonpaste.org)
# Licensed under the MIT license: http://www.opensource.org/licenses/mit-license.php
"""
Module to find differences over time in a filesystem
Basically this takes a snapshot of a directory, then sees what changes
were made. The contents of the files are not checked, so you can
detect that the content was changed, but not what the old version of
the file was.
"""
import os
from fnmatch import fnmatch
from datetime import datetime
try:
# Python 3
import collections.UserDict as IterableUserDict
except ImportError:
# Python 2.5-2.7
from UserDict import IterableUserDict
import operator
import re
__all__ = ['Diff', 'Snapshot', 'File', 'Dir', 'report_expected_diffs',
'show_diff']
class Diff(object):
"""
Represents the difference between two snapshots
"""
def __init__(self, before, after):
self.before = before
self.after = after
self._calculate()
def _calculate(self):
before = self.before.data
after = self.after.data
self.deleted = {}
self.updated = {}
self.created = after.copy()
for path, f in before.items():
if path not in after:
self.deleted[path] = f
continue
del self.created[path]
if f.mtime < after[path].mtime:
self.updated[path] = after[path]
def __str__(self):
return self.report()
def report(self, header=True, dates=False):
s = []
if header:
s.append('Difference in %s from %s to %s:' %
(self.before.base_path,
self.before.calculated,
self.after.calculated))
for name, files, show_size in [
('created', self.created, True),
('deleted', self.deleted, True),
('updated', self.updated, True)]:
if files:
s.append('-- %s: -------------------' % name)
files = files.items()
files.sort()
last = ''
for path, f in files:
t = ' %s' % _space_prefix(last, path, indent=4,
include_sep=False)
last = path
if show_size and f.size != 'N/A':
t += ' (%s bytes)' % f.size
if dates:
parts = []
if self.before.get(path):
parts.append(self.before[path].mtime)
if self.after.get(path):
parts.append(self.after[path].mtime)
t += ' (mtime: %s)' % ('->'.join(map(repr, parts)))
s.append(t)
if len(s) == 1:
s.append(' (no changes)')
return '\n'.join(s)
class Snapshot(IterableUserDict):
"""
Represents a snapshot of a set of files. Has a dictionary-like
interface, keyed relative to ``base_path``
"""
def __init__(self, base_path, files=None, ignore_wildcards=(),
ignore_paths=(), ignore_hidden=True):
self.base_path = base_path
self.ignore_wildcards = ignore_wildcards
self.ignore_hidden = ignore_hidden
self.ignore_paths = ignore_paths
self.calculated = None
self.data = files or {}
if files is None:
self.find_files()
############################################################
## File finding
############################################################
def find_files(self):
"""
Find all the files under the base path, and put them in
``self.data``
"""
self._find_traverse('', self.data)
self.calculated = datetime.now()
def _ignore_file(self, fn):
if fn in self.ignore_paths:
return True
if self.ignore_hidden and os.path.basename(fn).startswith('.'):
return True
for pat in self.ignore_wildcards:
if fnmatch(fn, pat):
return True
return False
def _find_traverse(self, path, result):
full = os.path.join(self.base_path, path)
if os.path.isdir(full):
if path:
# Don't actually include the base path
result[path] = Dir(self.base_path, path)
for fn in os.listdir(full):
fn = os.path.join(path, fn)
if self._ignore_file(fn):
continue
self._find_traverse(fn, result)
else:
result[path] = File(self.base_path, path)
def __repr__(self):
return '<%s in %r from %r>' % (
self.__class__.__name__, self.base_path,
self.calculated or '(no calculation done)')
def compare_expected(self, expected, comparison=operator.eq,
differ=None, not_found=None,
include_success=False):
"""
Compares a dictionary of ``path: content`` to the
found files. Comparison is done by equality, or the
``comparison(actual_content, expected_content)`` function given.
Returns dictionary of differences, keyed by path. Each
difference is either noted, or the output of
``differ(actual_content, expected_content)`` is given.
If a file does not exist and ``not_found`` is given, then
``not_found(path)`` is put in.
"""
result = {}
for path in expected:
orig_path = path
path = path.strip('/')
if path not in self.data:
if not_found:
msg = not_found(path)
else:
msg = 'not found'
result[path] = msg
continue
expected_content = expected[orig_path]
file = self.data[path]
actual_content = file.bytes
if not comparison(actual_content, expected_content):
if differ:
msg = differ(actual_content, expected_content)
else:
if len(actual_content) < len(expected_content):
msg = 'differ (%i bytes smaller)' % (
len(expected_content) - len(actual_content))
elif len(actual_content) > len(expected_content):
msg = 'differ (%i bytes larger)' % (
len(actual_content) - len(expected_content))
else:
msg = 'diff (same size)'
result[path] = msg
elif include_success:
result[path] = 'same!'
return result
def diff_to_now(self):
return Diff(self, self.clone())
def clone(self):
return self.__class__(base_path=self.base_path,
ignore_wildcards=self.ignore_wildcards,
ignore_paths=self.ignore_paths,
ignore_hidden=self.ignore_hidden)
class File(object):
"""
Represents a single file found as the result of a command.
Has attributes:
``path``:
The path of the file, relative to the ``base_path``
``full``:
The full path
``stat``:
The results of ``os.stat``. Also ``mtime`` and ``size``
contain the ``.st_mtime`` and ``st_size`` of the stat.
``bytes``:
The contents of the file.
You may use the ``in`` operator with these objects (tested against
the contents of the file), and the ``.mustcontain()`` method.
"""
file = True
dir = False
def __init__(self, base_path, path):
self.base_path = base_path
self.path = path
self.full = os.path.join(base_path, path)
self.stat = os.stat(self.full)
self.mtime = self.stat.st_mtime
self.size = self.stat.st_size
self._bytes = None
def bytes__get(self):
if self._bytes is None:
f = open(self.full, 'rb')
self._bytes = f.read()
f.close()
return self._bytes
bytes = property(bytes__get)
def __contains__(self, s):
return s in self.bytes
def mustcontain(self, s):
__tracebackhide__ = True
bytes = self.bytes
if s not in bytes:
print('Could not find %r in:' % s)
print(bytes)
assert s in bytes
def __repr__(self):
return '<%s %s:%s>' % (
self.__class__.__name__,
self.base_path, self.path)
class Dir(File):
"""
Represents a directory created by a command.
"""
file = False
dir = True
def __init__(self, base_path, path):
self.base_path = base_path
self.path = path
self.full = os.path.join(base_path, path)
self.size = 'N/A'
self.mtime = 'N/A'
def __repr__(self):
return '<%s %s:%s>' % (
self.__class__.__name__,
self.base_path, self.path)
def bytes__get(self):
raise NotImplementedError(
"Directory %r doesn't have content" % self)
bytes = property(bytes__get)
def _space_prefix(pref, full, sep=None, indent=None, include_sep=True):
"""
Anything shared by pref and full will be replaced with spaces
in full, and full returned.
Example::
>>> _space_prefix('/foo/bar', '/foo')
' /bar'
"""
if sep is None:
sep = os.path.sep
pref = pref.split(sep)
full = full.split(sep)
padding = []
while pref and full and pref[0] == full[0]:
if indent is None:
padding.append(' ' * (len(full[0]) + len(sep)))
else:
padding.append(' ' * indent)
full.pop(0)
pref.pop(0)
if padding:
if include_sep:
return ''.join(padding) + sep + sep.join(full)
else:
return ''.join(padding) + sep.join(full)
else:
return sep.join(full)
def report_expected_diffs(diffs, colorize=False):
"""
Takes the output of compare_expected, and returns a string
description of the differences.
"""
if not diffs:
return 'No differences'
diffs = diffs.items()
diffs.sort()
s = []
last = ''
for path, desc in diffs:
t = _space_prefix(last, path, indent=4, include_sep=False)
if colorize:
t = color_line(t, 11)
last = path
if len(desc.splitlines()) > 1:
cur_indent = len(re.search(r'^[ ]*', t).group(0))
desc = indent(cur_indent+2, desc)
if colorize:
t += '\n'
for line in desc.splitlines():
if line.strip().startswith('+'):
line = color_line(line, 10)
elif line.strip().startswith('-'):
line = color_line(line, 9)
else:
line = color_line(line, 14)
t += line+'\n'
else:
t += '\n' + desc
else:
t += ' '+desc
s.append(t)
s.append('Files with differences: %s' % len(diffs))
return '\n'.join(s)
def color_code(foreground=None, background=None):
"""
0 black
1 red
2 green
3 yellow
4 blue
5 magenta (purple)
6 cyan
7 white (gray)
Add 8 to get high-intensity
"""
if foreground is None and background is None:
# Reset
return '\x1b[0m'
codes = []
if foreground is None:
codes.append('[39m')
elif foreground > 7:
codes.append('[1m')
codes.append('[%im' % (22+foreground))
else:
codes.append('[%im' % (30+foreground))
if background is None:
codes.append('[49m')
else:
codes.append('[%im' % (40+background))
return '\x1b' + '\x1b'.join(codes)
def color_line(line, foreground=None, background=None):
match = re.search(r'^(\s*)', line)
return (match.group(1) + color_code(foreground, background)
+ line[match.end():] + color_code())
def indent(indent, text):
return '\n'.join(
[' '*indent + l for l in text.splitlines()])
def show_diff(actual_content, expected_content):
actual_lines = [l.strip() for l in actual_content.splitlines()
if l.strip()]
expected_lines = [l.strip() for l in expected_content.splitlines()
if l.strip()]
if len(actual_lines) == len(expected_lines) == 1:
return '%r not %r' % (actual_lines[0], expected_lines[0])
if not actual_lines:
return 'Empty; should have:\n'+expected_content
import difflib
return '\n'.join(difflib.ndiff(actual_lines, expected_lines))