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35 A memorizing file wraps a file and memorizes lines read by readline.
42 class MemorizingFile(object):
43 """MemorizingFile wraps a file and memorizes lines read by readline.
45 Note that data read by other methods are not memorized. This behavior
46 is good enough for memorizing lines SimpleHTTPServer reads before
47 the control reaches WebSocketRequestHandler.
50 def __init__(self, file_, max_memorized_lines=sys.maxint):
51 """Construct an instance.
54 file_: the file object to wrap.
55 max_memorized_lines: the maximum number of lines to memorize.
56 Only the first max_memorized_lines are memorized.
61 self._memorized_lines = []
62 self._max_memorized_lines = max_memorized_lines
63 self._buffered = False
64 self._buffered_line = None
66 def __getattribute__(self, name):
67 if name in ('_file', '_memorized_lines', '_max_memorized_lines',
68 '_buffered', '_buffered_line', 'readline',
69 'get_memorized_lines'):
70 return object.__getattribute__(self, name)
71 return self._file.__getattribute__(name)
73 def readline(self, size=-1):
74 """Override file.readline and memorize the line read.
76 Note that even if size is specified and smaller than actual size,
77 the whole line will be read out from underlying file object by
78 subsequent readline calls.
82 line = self._buffered_line
83 self._buffered = False
85 line = self._file.readline()
86 if line and len(self._memorized_lines) < self._max_memorized_lines:
87 self._memorized_lines.append(line)
88 if size >= 0 and size < len(line):
90 self._buffered_line = line[size:]
94 def get_memorized_lines(self):
95 """Get lines memorized so far."""
96 return self._memorized_lines