我编写了一个非常简单的 IMAP UTF7 python 3 实现,它遵循规范,它似乎可以工作。("foo\rbar\n\n\n\r\r" 和许多其他往返, '&BdAF6QXkBdQ-', 'Test&Co', "[Mails].Test&AOk-" 和 '~peter/mail/&ZeVnLIqe-/&U, BTFw-' 表现如预期)。
#works with python 3
import base64
def b64padanddecode(b):
"""Decode unpadded base64 data"""
b+=(-len(b)%4)*'=' #base64 padding (if adds '===', no valid padding anyway)
return base64.b64decode(b,altchars='+,',validate=True).decode('utf-16-be')
def imaputf7decode(s):
"""Decode a string encoded according to RFC2060 aka IMAP UTF7.
Minimal validation of input, only works with trusted data"""
lst=s.split('&')
out=lst[0]
for e in lst[1:]:
u,a=e.split('-',1) #u: utf16 between & and 1st -, a: ASCII chars folowing it
if u=='' : out+='&'
else: out+=b64padanddecode(u)
out+=a
return out
def imaputf7encode(s):
""""Encode a string into RFC2060 aka IMAP UTF7"""
s=s.replace('&','&-')
iters=iter(s)
unipart=out=''
for c in s:
if 0x20<=ord(c)<=0x7f :
if unipart!='' :
out+='&'+base64.b64encode(unipart.encode('utf-16-be')).decode('ascii').rstrip('=')+'-'
unipart=''
out+=c
else : unipart+=c
if unipart!='' :
out+='&'+base64.b64encode(unipart.encode('utf-16-be')).decode('ascii').rstrip('=')+'-'
return out
鉴于此代码的简单性,我将其设置在公共域中,因此请随意使用它。