Module gzipstream :: Class GzipStream
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Class GzipStream

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     object --+                
              |                
    _io._IOBase --+            
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_io._BufferedIOBase --+        
                      |        
     object --+       |        
              |       |        
    _io._IOBase --+   |        
                  |   |        
          io.IOBase --+        
                      |        
      io.BufferedIOBase --+    
                          |    
              gzip.GzipFile --+
                              |
                             GzipStream

Handle streaming gzipped data

GzipStream extends the functionality of the gzip.GzipFile class. gzip.GzipFile generally needs a seekable object. This doesn't allow for streaming gzipped data to be processed easily (e.g. can't seek a socket). Using the _StreamBuf class enables streaming gzipped data to be processed by buffering that data at it passes through.

For Python versions 1.5.2 & 2.1.*: Normal data version. Normally sized data stream version == faster. For very large data streams (2.5GB-ish), use GzipStreamXL.

Nested Classes [hide private]

Inherited from io.IOBase: __metaclass__

Instance Methods [hide private]
 
__init__(self, stream=None, mode=None, compresslevel=9)
Constructor for the GzipFile class.
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_initModeLogic(self, stream, mode)
attempt to determine the mode
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_read(self, size=1024) source code
 
seek(self, offset)
Change stream position.
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__repr__(self)
repr(x)
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_read_eof(self) source code
 
close(self)
Flush and close the IO object.
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_read32XL(self, input)
Allow for very large files/streams to be processed.
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Inherited from gzip.GzipFile: fileno, flush, read, readable, readline, rewind, seekable, writable, write

Inherited from gzip.GzipFile (private): _add_read_data, _check_closed, _init_read, _init_write, _read_gzip_header, _unread, _write_gzip_header

Inherited from _io._BufferedIOBase: detach, read1, readinto

Inherited from _io._IOBase: __enter__, __exit__, __iter__, __new__, isatty, next, readlines, tell, truncate, writelines

Inherited from _io._IOBase (private): _checkClosed, _checkReadable, _checkSeekable, _checkWritable

Inherited from object: __delattr__, __format__, __getattribute__, __hash__, __reduce__, __reduce_ex__, __setattr__, __sizeof__, __str__, __subclasshook__

Class Variables [hide private]
  VERSION = 2

Inherited from gzip.GzipFile: max_read_chunk, myfileobj

Inherited from gzip.GzipFile (private): _abc_negative_cache, _abc_negative_cache_version, _abc_registry

Inherited from io.IOBase: __abstractmethods__

Inherited from io.IOBase (private): _abc_cache

Properties [hide private]

Inherited from gzip.GzipFile: closed, filename

Inherited from object: __class__

Method Details [hide private]

__init__(self, stream=None, mode=None, compresslevel=9)
(Constructor)

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Constructor for the GzipFile class.

At least one of fileobj and filename must be given a non-trivial value.

The new class instance is based on fileobj, which can be a regular file, a StringIO object, or any other object which simulates a file. It defaults to None, in which case filename is opened to provide a file object.

When fileobj is not None, the filename argument is only used to be included in the gzip file header, which may includes the original filename of the uncompressed file. It defaults to the filename of fileobj, if discernible; otherwise, it defaults to the empty string, and in this case the original filename is not included in the header.

The mode argument can be any of 'r', 'rb', 'a', 'ab', 'w', or 'wb', depending on whether the file will be read or written. The default is the mode of fileobj if discernible; otherwise, the default is 'rb'. Be aware that only the 'rb', 'ab', and 'wb' values should be used for cross-platform portability.

The compresslevel argument is an integer from 1 to 9 controlling the level of compression; 1 is fastest and produces the least compression, and 9 is slowest and produces the most compression. The default is 9.

The mtime argument is an optional numeric timestamp to be written to the stream when compressing. All gzip compressed streams are required to contain a timestamp. If omitted or None, the current time is used. This module ignores the timestamp when decompressing; however, some programs, such as gunzip, make use of it. The format of the timestamp is the same as that of the return value of time.time() and of the st_mtime member of the object returned by os.stat().

Overrides: object.__init__
(inherited documentation)

_read(self, size=1024)

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Overrides: gzip.GzipFile._read

seek(self, offset)

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Change stream position.

Change the stream position to byte offset offset. offset is interpreted relative to the position indicated by whence. Values for whence are:

* 0 -- start of stream (the default); offset should be zero or positive * 1 -- current stream position; offset may be negative * 2 -- end of stream; offset is usually negative

Return the new absolute position.

Overrides: _io._IOBase.seek
(inherited documentation)

__repr__(self)
(Representation operator)

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repr(x)

Overrides: object.__repr__
(inherited documentation)

_read_eof(self)

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Overrides: gzip.GzipFile._read_eof

close(self)

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Flush and close the IO object.

This method has no effect if the file is already closed.

Overrides: _io._IOBase.close
(inherited documentation)

_read32XL(self, input)

source code 
Allow for very large files/streams to be processed.
   Slows things down, but...

Used by Python v2.2.*.
Also used by Python v1.5.2/v2.1.* in inheriting class GzipStreamXL.