1 <?xml version="1.0" standalone="no"?>
2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.1//EN"
3 "http://www.oasis-open.org/docbook/xml/4.1/docbook.dtd">
5 <refentry id="mimedecode.py">
8 <refentrytitle>mimedecode.py</refentrytitle>
9 <manvolnum>1</manvolnum>
13 <refname>mimedecode.py</refname>
14 <refpurpose>decode MIME message</refpurpose>
19 <command>mimedecode.py</command>
21 <option>-h|--help</option>
24 <option>-V|--version</option>
27 <option>-cCDP</option>
30 <option>-f charset</option>
33 <option>-d header</option>
36 <option>-p header:param</option>
39 <option>-beit mask</option>
41 <arg choice="opt">input_file
42 <arg choice="opt">output_file</arg>
49 <title>DESCRIPTION</title>
51 Mail users, especially in non-English countries, often find that mail
52 messages arrived in different formats, with different content types, in
53 different encodings and charsets. Usually it is good because it allows to use
54 an appropriate format/encoding/whatever. Sometimes, though, some unification is
55 desirable. For example, one may want to put mail messages into an archive,
56 make HTML indices, run search indexer, etc. In such situations converting
57 messages to text in one character set and skipping some binary attachments is
62 Here is the solution - mimedecode.py!
66 It is a program to decode MIME messages. The program expects one input file
67 (either on the command line or on stdin) which is treated as an RFC822 message,
68 and decoded to stdout. If the file is not an RFC822 message it is just piped to
69 stdout as is. If the file is a simple RFC822 message it is just decoded as one
70 part. If it is a MIME message with multiple parts ("attachments") all parts are
71 decoded recursively. Decoding can be controlled by the command-line options.
75 First, Subject and Content-Disposition headers are examined. If any of those
76 exists, it is decoded according to RFC2047. Content-Disposition header is not
77 decoded - only its "filename" parameter. Encoded header parameters violate
78 the RFC, but widely deployed anyway, especially in the M$ Ophice GUI (often
79 referred as "Windoze") world, where programmers are often ignorant lamers who
80 never even heard about RFCs. Correct parameter encoding specified by RFC2231.
81 This program decodes RFC2231-encoded parameters, too.
85 Then the body of the message (or the current part) is decoded. Decoding
86 starts with looking at header Content-Transfer-Encoding. If the header
87 specifies non-8bit encoding (usually base64 or quoted-printable), the body
88 converted to 8bit. Then, if its content type is multipart (multipart/related or
89 multipart/mixed, e.g) every part is recursively decoded. If it is not
90 multipart, mailcap database is consulted to find a way to convert the body to
91 plain text. (I have no idea how mailcap could be configured on said M$ Ophice
92 GUI, please don't ask me; real OS users can consult my example at
93 http://phdru.name/Software/dotfiles/mailcap.html). The decoding process uses
94 first copiousoutput filter it can find. If there is no any filter the body just
99 Then Content-Type header consulted for charset. If it is not equal to
100 current default charset the body text recoded. Finally message headers and body
107 <title>OPTIONS</title>
114 Print brief usage help and exit.
121 <term>--version</term>
124 Print version and exit.
133 Recode different character sets in message body to current default
134 charset; this is the default.
143 Do not recode character sets in message body.
149 <term>-f charset</term>
152 Force this charset to be the current default charset instead of
153 sys.getdefaultencoding().
159 <term>-d header</term>
162 Add the header to a list of headers to decode; initially the list
163 contains headers "From" and "Subject".
172 Clear the list of headers to decode (make it empty).
178 <term>-p header:param</term>
181 Add the (header, param) pair to a list of headers' parameters to
182 decode; initially the list contains header "Content-Disposition",
183 parameter "filename".
192 Clear the list of headers' parameters to decode (make it empty).
201 Append mask to the list of binary content types; if the message to
202 decode has a part of this type the program will pass the part as is,
203 without any additional processing.
212 Append mask to the list of error content types; if the message to
213 decode has a part of this type the program will raise ValueError.
222 Append mask to the list of content types to ignore; if the message to
223 decode has a part of this type the program will not pass it, instead
224 a line "Message body of type `%s' skipped." will be issued.
233 Append mask to the list of content types to convert to text; if the
234 message to decode has a part of this type the program will consult
235 mailcap database, find first copiousoutput filter and convert the
243 The last 4 options (-beit) require more explanation. They allow a user
244 to control body decoding with great flexibility. Think about said mail
245 archive; for example, its maintainer wants to put there only texts, convert
246 Postscript/PDF to text, pass HTML and images as is, and ignore everything
251 <code language="shell">
252 mimedecode.py -t application/postscript -t application/pdf -b text/html
253 -b 'image/*' -i '*/*'
258 When the program decodes a message (or its part), it consults
259 Content-Type header. The content type is searched in all 4 lists, in order
260 "text-binary-ignore-error". If found, appropriate action performed. If not
261 found, the program search the same lists for "type/*" mask (the type of
262 "text/html" is just "text"). If found, appropriate action performed. If not
263 found, the program search the same lists for "*/*" mask. If found,
264 appropriate action performed. If not found, the program uses default
265 action, which is to decode everything to text (if mailcap specifies
270 Initially all 4 lists are empty, so without any additional parameters
271 the program always uses the default decoding.
277 <title>ENVIRONMENT</title>
282 Define current locale settings. Used to determine current default
283 charset (if your Python is properly installed and configured).
291 The program may produce incorrect MIME message. The purpose of the program
292 is to decode whatever it is possible to decode, not to produce absolutely
293 correct MIME output. The incorrect parts are obvious - decoded Subject headers
294 and filenames. Other than that output is correct MIME message. The program does
295 not try to guess whether the headers are correct. For example, if a message
296 header states that charset is iso8859-5, but the body is actually in koi8-r -
297 the program will recode the message to the wrong charset.
303 <title>AUTHOR</title>
305 Oleg Broytman <phd@phdru.name>
311 <title>COPYRIGHT</title>
313 Copyright (C) 2001-2014 PhiloSoft Design
319 <title>LICENSE</title>
327 <title>NO WARRANTIES</title>
329 This program is distributed in the hope that it will be useful, but WITHOUT
330 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
331 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
338 <title>SEE ALSO</title>
340 mimedecode.py home page: http://phdru.name/Software/Python/#mimedecode