You should use io.StringIO for handling unicode objects and io.BytesIO for handling bytes objects in both python 2 and 3, for forwards-compatibility (this is all 3 has to offer). Here’s a better test (for python 2 and 3), that doesn’t include conversion costs from numpy to str/bytes import numpy as np import string b_data = … Read more
You need to seek to the beginning of compressedFile after writing to it but before passing it to gzip.GzipFile(). Otherwise it will be read from the end by gzip module and will appear as an empty file to it. See below: #! /usr/bin/env python import urllib2 import StringIO import gzip baseURL = “https://www.kernel.org/pub/linux/docs/man-pages/” filename = … Read more
the code in the accepted answer actually reads from the stream completely for decoding. Below is the right way, converting one stream to another, where the data can be read chunk by chunk. # Initialize a read buffer input = io.BytesIO( b’Inital value for read buffer with unicode characters ‘ + ‘ÁÇÊ’.encode(‘utf-8’) ) wrapper = … Read more
Generally it’s still better to call close() or use the with statement, because there may be some unexpected behaviour in special circumstances. For example, the expat-IncrementalParser seems to expect a file to be closed, or it won’t return the last tidbit of parsed xml until a timeout occurs in some rare circumstances. But for the … Read more
The issue here is that in Python 3 you need to use StringIO with csv.write and send_file requires BytesIO, so you have to do both. @app.route(‘/test_download’) def test_download(): row = [‘hello’, ‘world’] proxy = io.StringIO() writer = csv.writer(proxy) writer.writerow(row) # Creating the byteIO object from the StringIO Object mem = io.BytesIO() mem.write(proxy.getvalue().encode()) # seeking was … Read more
Basically, it makes a string look like an IO object, hence the name StringIO. The StringIO class has read and write methods, so it can be passed to parts of your code that were designed to read and write from files or sockets. It’s nice if you have a string and you want it to … Read more
The main advantage of StringIO is that it can be used where a file was expected. So you can do for example (for Python 2): import sys import StringIO out = StringIO.StringIO() sys.stdout = out print “hi, I’m going out” sys.stdout = sys.__stdout__ print out.getvalue()
Use shutil.copyfileobj: with open(‘file.xml’, ‘w’) as fd: buf.seek(0) shutil.copyfileobj(buf, fd) or shutil.copyfileobj(buf, fd, -1) to copy from a file object without using chunks of limited size (used to avoid uncontrolled memory consumption).
TL;DR Don’t bother clearing it, just create a new one—it’s faster. The method Python 2 Here’s how I would find such things out: >>> from StringIO import StringIO >>> dir(StringIO) [‘__doc__’, ‘__init__’, ‘__iter__’, ‘__module__’, ‘close’, ‘flush’, ‘getvalue’, ‘isatty’, ‘next’, ‘read’, ‘readline’, ‘readlines’, ‘seek’, ‘tell’, ‘truncate’, ‘write’, ‘writelines’] >>> help(StringIO.truncate) Help on method truncate in module … Read more
Try io.BytesIO. As others have pointed out, you can indeed use StringIO in 2.7, but BytesIO is a good choice for forward-compatibility.