The email package version 1.0, prototyped as mimelib

<http://sf.net/projects/mimelib>.  There /are/ API differences between
mimelib and email, but most of the implementations are shared (except
where cool Py2.2 stuff like generators are used).

Lib/email/Utils.py

@@ -0,0 +1,104 @@
+# Copyright (C) 2001 Python Software Foundation
+# Author: barry@zope.com (Barry Warsaw)
+
+"""Miscellaneous utilities.
+"""
+
+import re
+
+from rfc822 import unquote, quote, parseaddr
+from rfc822 import dump_address_pair
+from rfc822 import AddrlistClass as _AddrlistClass
+from rfc822 import parsedate_tz, parsedate, mktime_tz, formatdate
+
+from quopri import decodestring as _qdecode
+import base64
+
+# Intrapackage imports
+from Encoders import _bencode, _qencode
+
+COMMASPACE = ', '
+UEMPTYSTRING = u''
+
+
+
+# Helpers
+
+def _identity(s):
+    return s
+
+
+def _bdecode(s):
+    if not s:
+        return s
+    # We can't quite use base64.encodestring() since it tacks on a "courtesy
+    # newline".  Blech!
+    if not s:
+        return s
+    hasnewline = (s[-1] == '\n')
+    value = base64.decodestring(s)
+    if not hasnewline and value[-1] == '\n':
+        return value[:-1]
+    return value
+
+
+
+def getaddresses(fieldvalues):
+    """Return a list of (REALNAME, EMAIL) for each fieldvalue."""
+    all = COMMASPACE.join(fieldvalues)
+    a = _AddrlistClass(all)
+    return a.getaddrlist()
+
+
+
+ecre = re.compile(r'''
+  =\?                   # literal =?
+  (?P<charset>[^?]*?)   # non-greedy up to the next ? is the charset
+  \?                    # literal ?
+  (?P<encoding>[qb])    # either a "q" or a "b", case insensitive
+  \?                    # literal ?
+  (?P<atom>.*?)         # non-greedy up to the next ?= is the atom
+  \?=                   # literal ?=
+  ''', re.VERBOSE | re.IGNORECASE)
+
+
+def decode(s):
+    """Return a decoded string according to RFC 2047, as a unicode string."""
+    rtn = []
+    parts = ecre.split(s, 1)
+    while parts:
+        # If there are less than 4 parts, it can't be encoded and we're done
+        if len(parts) < 5:
+            rtn.extend(parts)
+            break
+        # The first element is any non-encoded leading text
+        rtn.append(parts[0])
+        charset = parts[1]
+        encoding = parts[2]
+        atom = parts[3]
+        # The next chunk to decode should be in parts[4]
+        parts = ecre.split(parts[4])
+        # The encoding must be either `q' or `b', case-insensitive
+        if encoding.lower() == 'q':
+            func = _qdecode
+        elif encoding.lower() == 'b':
+            func = _bdecode
+        else:
+            func = _identity
+        # Decode and get the unicode in the charset
+        rtn.append(unicode(func(atom), charset))
+    # Now that we've decoded everything, we just need to join all the parts
+    # together into the final string.
+    return UEMPTYSTRING.join(rtn)
+
+
+
+def encode(s, charset='iso-8859-1', encoding='q'):
+    """Encode a string according to RFC 2047."""
+    if encoding.lower() == 'q':
+        estr = _qencode(s)
+    elif encoding.lower() == 'b':
+        estr = _bencode(s)
+    else:
+        raise ValueError, 'Illegal encoding code: ' + encoding
+    return '=?%s?%s?%s?=' % (charset.lower(), encoding.lower(), estr)