Convert from '_io.BytesIO' to a bytes-like object in python3.6?
PythonPython 3.xTypeerrorZlibBytesioPython Problem Overview
I am using this function to uncompress the body or a HTTP response if it is compressed with gzip, compress or deflate.
def uncompress_body(self, compression_type, body):
if compression_type == 'gzip' or compression_type == 'compress':
return zlib.decompress(body)
elif compression_type == 'deflate':
compressor = zlib.compressobj(9, zlib.DEFLATED, -zlib.MAX_WBITS)
compressed = compressor.compress(body)
compressed += compressor.flush()
return base64.b64encode(compressed)
return body
However python throws this error message.
TypeError: a bytes-like object is required, not '_io.BytesIO'
on this line:
return zlib.decompress(body)
Essentially, how do I convert from '_io.BytesIO' to a bytes-like object?
Python Solutions
Solution 1 - Python
It's a file-like object. Read them:
>>> b = io.BytesIO(b'hello')
>>> b.read()
b'hello'
If the data coming in from body is too large to read into memory, you'll want to refactor your code and use zlib.decompressobj instead of zlib.decompress.
Solution 2 - Python
In case you write into the object first, make sure to reset the stream before reading:
>>> b = io.BytesIO()
>>> image = PIL.Image.open(path_to_image)
>>> image.save(b, format='PNG')
>>> b.seek(0)
>>> b.read()
b'\x89PNG\r\n\x1a\n\x00\x00\x00\rIHDR\x00\x00\x06\xcf\x00\x00\x03W\x08\x02\x00'
or directly get the data with getvalue
>>> b.getvalue()
b'\x89PNG\r\n\x1a\n\x00\x00\x00\rIHDR\x00\x00\x06\xcf\x00\x00\x03W\x08\x02\x00'
Solution 3 - Python
b = io.BytesIO()
image = PIL.Image.open(path_to_image) # ie 'image.png'
image.save(b, format='PNG')
b.getbuffer().tobytes() # b'\x89PNG\r\n\x1a\n\x00 ...