使用python cgi上传文件并计算m
- 2020 年 1 月 13 日
- 笔记
对文件拷贝后进行MD5值比较，看是不是拷贝完全。google和baidu上都是使用md5模块读取所有的文件进内存，在计算md5，导致计算超过1G大小的文件报错。增量计算MD5的方法：
#!/usr/bin/python import hashlib import sys def main(): if len(sys.argv) != 2: sys.exit('usage:%s file' % sys.argv[0]) filename = sys.argv[1] md5 = hashlib.md5() with open(filename,'rb') as fp: while True: blk = fp.read(4096) if not blk:break md5.update(blk) print md5.hexdigest(),filename if __name__ == '__main__': main()
这个效果一样，使用md5，上面使用的hashlib:
#!/usr/bin/python import md5 import sys def main(): if len(sys.argv) != 2: sys.exit('usage:%s file' % sys.argv[0]) filename = sys.argv[1] m = md5.new() with open(filename,'rb') as fp: while True: blk = fp.read(4096) if not blk:break m.update(blk) print m.hexdigest(),filename if __name__ == '__main__': main()
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上面例子的应用
计算上传文件的md5值，并显示文件大小：
#!/usr/bin/python # -*- coding:utf-8 -*- import cgi, os import cgitb; cgitb.enable() import md5 form = cgi.FieldStorage() fileitem = form['filename'] if fileitem.filename: #fn = os.path.basename(fileitem.filename) #open('/tmp/' + fn, 'wb').write(fileitem.file.read()) message = 'Got file %s"' % cgi.escape(fileitem.filename) m = md5.new() size = 0 while True: data = fileitem.file.read(4096) if not len(data): break size += len(data) m.update(data) #open('/tmp/' + fn, 'wb').write(data) li = 'Received file of %d bytes. MD5sum is %s' % (size,m.hexdigest()) else: message = 'No file was uploaded' print """ Content-Type: text/htmln <html> <body> <p>%s</p> <p>%s</p> </body> </html> """ % (message,li)
MD5.html:
<html> <body> <form enctype="multipart/form-data" action="/op/md5_file.py" method="post"> <p>File: <input type="file" name="filename" /></p> <p><input type="submit" value="md5" /></p> </form> </body> </html>
效果：
点击md5，计算文件的md5值
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跟上个例子类似，功能不一样
python cgi上传文件：
#!/usr/bin/python # -*- coding:utf-8 -*- import cgi, os import cgitb; cgitb.enable() form = cgi.FieldStorage() # 获取文件名 fileitem = form['filename'] # 检测文件是否上传 if fileitem.filename: # 设置文件路径 fn = os.path.basename(fileitem.filename) open('/tmp/' + fn, 'wb').write(fileitem.file.read()) message = 'The file "' + fn + '" was uploaded successfully' else: message = 'No file was uploaded' print """ Content-Type: text/htmln <html> <body> <p>%s</p> </body> </html> """ % (message,)
index.html
<html> <body> <form enctype="multipart/form-data" action="/op/save_file.py" method="post"> <p>File: <input type="file" name="filename" /></p> <p><input type="submit" value="Upload" /></p> </form> </body> </html>
效果：
点击Upload，显示上传成功
