Big File UploadΒΆ
To handle big files without using all the available memory a generator can be used. The generator will return the file in small chunks:
#!/usr/bin/env python
import cgi, os
import cgitb; cgitb.enable()
try: # Windows needs stdio set for binary mode.
import msvcrt
msvcrt.setmode (0, os.O_BINARY) # stdin = 0
msvcrt.setmode (1, os.O_BINARY) # stdout = 1
except ImportError:
pass
form = cgi.FieldStorage()
# Generator to buffer file chunks
def fbuffer(f, chunk_size=10000):
while True:
chunk = f.read(chunk_size)
if not chunk: break
yield chunk
# A nested FieldStorage instance holds the file
fileitem = form['file']
# Test if the file was uploaded
if fileitem.filename:
# strip leading path from file name to avoid directory traversal attacks
fn = os.path.basename(fileitem.filename)
f = open('files/' + fn, 'wb', 10000)
# Read the file in chunks
for chunk in fbuffer(fileitem.file):
f.write(chunk)
f.close()
message = 'The file "' + fn + '" was uploaded successfully'
else:
message = 'No file was uploaded'
print """\
Content-Type: text/html\n
<html><body>
<p>%s</p>
</body></html>
""" % (message,)