Vega strike Python Modules doc  0.5.1
Documentation of the " Modules " folder of Vega strike
 All Data Structures Namespaces Files Functions Variables
MimeWriter.py
Go to the documentation of this file.
1 """Generic MIME writer.
2 
3 Classes:
4 
5 MimeWriter - the only thing here.
6 
7 """
8 
9 
10 import mimetools
11 
12 __all__ = ["MimeWriter"]
13 
14 class MimeWriter:
15 
16  """Generic MIME writer.
17 
18  Methods:
19 
20  __init__()
21  addheader()
22  flushheaders()
23  startbody()
24  startmultipartbody()
25  nextpart()
26  lastpart()
27 
28  A MIME writer is much more primitive than a MIME parser. It
29  doesn't seek around on the output file, and it doesn't use large
30  amounts of buffer space, so you have to write the parts in the
31  order they should occur on the output file. It does buffer the
32  headers you add, allowing you to rearrange their order.
33 
34  General usage is:
35 
36  f = <open the output file>
37  w = MimeWriter(f)
38  ...call w.addheader(key, value) 0 or more times...
39 
40  followed by either:
41 
42  f = w.startbody(content_type)
43  ...call f.write(data) for body data...
44 
45  or:
46 
47  w.startmultipartbody(subtype)
48  for each part:
49  subwriter = w.nextpart()
50  ...use the subwriter's methods to create the subpart...
51  w.lastpart()
52 
53  The subwriter is another MimeWriter instance, and should be
54  treated in the same way as the toplevel MimeWriter. This way,
55  writing recursive body parts is easy.
56 
57  Warning: don't forget to call lastpart()!
58 
59  XXX There should be more state so calls made in the wrong order
60  are detected.
61 
62  Some special cases:
63 
64  - startbody() just returns the file passed to the constructor;
65  but don't use this knowledge, as it may be changed.
66 
67  - startmultipartbody() actually returns a file as well;
68  this can be used to write the initial 'if you can read this your
69  mailer is not MIME-aware' message.
70 
71  - If you call flushheaders(), the headers accumulated so far are
72  written out (and forgotten); this is useful if you don't need a
73  body part at all, e.g. for a subpart of type message/rfc822
74  that's (mis)used to store some header-like information.
75 
76  - Passing a keyword argument 'prefix=<flag>' to addheader(),
77  start*body() affects where the header is inserted; 0 means
78  append at the end, 1 means insert at the start; default is
79  append for addheader(), but insert for start*body(), which use
80  it to determine where the Content-Type header goes.
81 
82  """
83 
84  def __init__(self, fp):
85  self._fp = fp
86  self._headers = []
87 
88  def addheader(self, key, value, prefix=0):
89  lines = value.split("\n")
90  while lines and not lines[-1]: del lines[-1]
91  while lines and not lines[0]: del lines[0]
92  for i in range(1, len(lines)):
93  lines[i] = " " + lines[i].strip()
94  value = "\n".join(lines) + "\n"
95  line = key + ": " + value
96  if prefix:
97  self._headers.insert(0, line)
98  else:
99  self._headers.append(line)
100 
101  def flushheaders(self):
102  self._fp.writelines(self._headers)
103  self._headers = []
104 
105  def startbody(self, ctype, plist=[], prefix=1):
106  for name, value in plist:
107  ctype = ctype + ';\n %s=\"%s\"' % (name, value)
108  self.addheader("Content-Type", ctype, prefix=prefix)
109  self.flushheaders()
110  self._fp.write("\n")
111  return self._fp
112 
113  def startmultipartbody(self, subtype, boundary=None, plist=[], prefix=1):
114  self._boundary = boundary or mimetools.choose_boundary()
115  return self.startbody("multipart/" + subtype,
116  [("boundary", self._boundary)] + plist,
117  prefix=prefix)
118 
119  def nextpart(self):
120  self._fp.write("\n--" + self._boundary + "\n")
121  return self.__class__(self._fp)
122 
123  def lastpart(self):
124  self._fp.write("\n--" + self._boundary + "--\n")
125 
126 
127 if __name__ == '__main__':
128  import test.test_MimeWriter