406 lines
10 KiB
Python
406 lines
10 KiB
Python
# RFC-822 message manipulation class.
|
|
#
|
|
# XXX This is only a very rough sketch of a full RFC-822 parser;
|
|
# in particular the tokenizing of addresses does not adhere to all the
|
|
# quoting rules.
|
|
#
|
|
# Directions for use:
|
|
#
|
|
# To create a Message object: first open a file, e.g.:
|
|
# fp = open(file, 'r')
|
|
# (or use any other legal way of getting an open file object, e.g. use
|
|
# sys.stdin or call os.popen()).
|
|
# Then pass the open file object to the Message() constructor:
|
|
# m = Message(fp)
|
|
#
|
|
# To get the text of a particular header there are several methods:
|
|
# str = m.getheader(name)
|
|
# str = m.getrawheader(name)
|
|
# where name is the name of the header, e.g. 'Subject'.
|
|
# The difference is that getheader() strips the leading and trailing
|
|
# whitespace, while getrawheader() doesn't. Both functions retain
|
|
# embedded whitespace (including newlines) exactly as they are
|
|
# specified in the header, and leave the case of the text unchanged.
|
|
#
|
|
# For addresses and address lists there are functions
|
|
# realname, mailaddress = m.getaddr(name) and
|
|
# list = m.getaddrlist(name)
|
|
# where the latter returns a list of (realname, mailaddr) tuples.
|
|
#
|
|
# There is also a method
|
|
# time = m.getdate(name)
|
|
# which parses a Date-like field and returns a time-compatible tuple,
|
|
# i.e. a tuple such as returned by time.localtime() or accepted by
|
|
# time.mktime().
|
|
#
|
|
# See the class definition for lower level access methods.
|
|
#
|
|
# There are also some utility functions here.
|
|
|
|
|
|
import regex
|
|
import string
|
|
import time
|
|
|
|
|
|
_blanklines = ('\r\n', '\n') # Optimization for islast()
|
|
|
|
|
|
class Message:
|
|
|
|
# Initialize the class instance and read the headers.
|
|
|
|
def __init__(self, fp, seekable = 1):
|
|
self.fp = fp
|
|
self.seekable = seekable
|
|
self.startofheaders = None
|
|
self.startofbody = None
|
|
#
|
|
if self.seekable:
|
|
try:
|
|
self.startofheaders = self.fp.tell()
|
|
except IOError:
|
|
self.seekable = 0
|
|
#
|
|
self.readheaders()
|
|
#
|
|
if self.seekable:
|
|
try:
|
|
self.startofbody = self.fp.tell()
|
|
except IOError:
|
|
self.seekable = 0
|
|
|
|
|
|
# Rewind the file to the start of the body (if seekable).
|
|
|
|
def rewindbody(self):
|
|
if not self.seekable:
|
|
raise IOError, "unseekable file"
|
|
self.fp.seek(self.startofbody)
|
|
|
|
|
|
# Read header lines up to the entirely blank line that
|
|
# terminates them. The (normally blank) line that ends the
|
|
# headers is skipped, but not included in the returned list.
|
|
# If a non-header line ends the headers, (which is an error),
|
|
# an attempt is made to backspace over it; it is never
|
|
# included in the returned list.
|
|
#
|
|
# The variable self.status is set to the empty string if all
|
|
# went well, otherwise it is an error message.
|
|
# The variable self.headers is a completely uninterpreted list
|
|
# of lines contained in the header (so printing them will
|
|
# reproduce the header exactly as it appears in the file).
|
|
|
|
def readheaders(self):
|
|
self.dict = {}
|
|
self.unixfrom = ''
|
|
self.headers = list = []
|
|
self.status = ''
|
|
headerseen = ""
|
|
firstline = 1
|
|
while 1:
|
|
line = self.fp.readline()
|
|
if not line:
|
|
self.status = 'EOF in headers'
|
|
break
|
|
# Skip unix From name time lines
|
|
if firstline and line[:5] == 'From ':
|
|
self.unixfrom = self.unixfrom + line
|
|
continue
|
|
firstline = 0
|
|
if self.islast(line):
|
|
break
|
|
elif headerseen and line[0] in ' \t':
|
|
# It's a continuation line.
|
|
list.append(line)
|
|
x = (self.dict[headerseen] + "\n " +
|
|
string.strip(line))
|
|
self.dict[headerseen] = string.strip(x)
|
|
elif ':' in line:
|
|
# It's a header line.
|
|
list.append(line)
|
|
i = string.find(line, ':')
|
|
headerseen = string.lower(line[:i])
|
|
self.dict[headerseen] = string.strip(
|
|
line[i+1:])
|
|
else:
|
|
# It's not a header line; stop here.
|
|
if not headerseen:
|
|
self.status = 'No headers'
|
|
else:
|
|
self.status = 'Bad header'
|
|
# Try to undo the read.
|
|
if self.seekable:
|
|
self.fp.seek(-len(line), 1)
|
|
else:
|
|
self.status = \
|
|
self.status + '; bad seek'
|
|
break
|
|
|
|
|
|
# Method to determine whether a line is a legal end of
|
|
# RFC-822 headers. You may override this method if your
|
|
# application wants to bend the rules, e.g. to strip trailing
|
|
# whitespace, or to recognise MH template separators
|
|
# ('--------'). For convenience (e.g. for code reading from
|
|
# sockets) a line consisting of \r\n also matches.
|
|
|
|
def islast(self, line):
|
|
return line in _blanklines
|
|
|
|
|
|
# Look through the list of headers and find all lines matching
|
|
# a given header name (and their continuation lines).
|
|
# A list of the lines is returned, without interpretation.
|
|
# If the header does not occur, an empty list is returned.
|
|
# If the header occurs multiple times, all occurrences are
|
|
# returned. Case is not important in the header name.
|
|
|
|
def getallmatchingheaders(self, name):
|
|
name = string.lower(name) + ':'
|
|
n = len(name)
|
|
list = []
|
|
hit = 0
|
|
for line in self.headers:
|
|
if string.lower(line[:n]) == name:
|
|
hit = 1
|
|
elif line[:1] not in string.whitespace:
|
|
hit = 0
|
|
if hit:
|
|
list.append(line)
|
|
return list
|
|
|
|
|
|
# Similar, but return only the first matching header (and its
|
|
# continuation lines).
|
|
|
|
def getfirstmatchingheader(self, name):
|
|
name = string.lower(name) + ':'
|
|
n = len(name)
|
|
list = []
|
|
hit = 0
|
|
for line in self.headers:
|
|
if hit:
|
|
if line[:1] not in string.whitespace:
|
|
break
|
|
elif string.lower(line[:n]) == name:
|
|
hit = 1
|
|
if hit:
|
|
list.append(line)
|
|
return list
|
|
|
|
|
|
# A higher-level interface to getfirstmatchingheader().
|
|
# Return a string containing the literal text of the header
|
|
# but with the keyword stripped. All leading, trailing and
|
|
# embedded whitespace is kept in the string, however.
|
|
# Return None if the header does not occur.
|
|
|
|
def getrawheader(self, name):
|
|
list = self.getfirstmatchingheader(name)
|
|
if not list:
|
|
return None
|
|
list[0] = list[0][len(name) + 1:]
|
|
return string.joinfields(list, '')
|
|
|
|
|
|
# The normal interface: return a stripped version of the
|
|
# header value with a name, or None if it doesn't exist. This
|
|
# uses the dictionary version which finds the *last* such
|
|
# header.
|
|
|
|
def getheader(self, name):
|
|
try:
|
|
return self.dict[string.lower(name)]
|
|
except KeyError:
|
|
return None
|
|
|
|
|
|
# Retrieve a single address from a header as a tuple, e.g.
|
|
# ('Guido van Rossum', 'guido@cwi.nl').
|
|
|
|
def getaddr(self, name):
|
|
try:
|
|
data = self[name]
|
|
except KeyError:
|
|
return None, None
|
|
return parseaddr(data)
|
|
|
|
# Retrieve a list of addresses from a header, where each
|
|
# address is a tuple as returned by getaddr().
|
|
|
|
def getaddrlist(self, name):
|
|
# XXX This function is not really correct. The split
|
|
# on ',' might fail in the case of commas within
|
|
# quoted strings.
|
|
try:
|
|
data = self[name]
|
|
except KeyError:
|
|
return []
|
|
data = string.splitfields(data, ',')
|
|
for i in range(len(data)):
|
|
data[i] = parseaddr(data[i])
|
|
return data
|
|
|
|
# Retrieve a date field from a header as a tuple compatible
|
|
# with time.mktime().
|
|
|
|
def getdate(self, name):
|
|
try:
|
|
data = self[name]
|
|
except KeyError:
|
|
return None
|
|
return parsedate(data)
|
|
|
|
|
|
# Access as a dictionary (only finds *last* header of each type):
|
|
|
|
def __len__(self):
|
|
return len(self.dict)
|
|
|
|
def __getitem__(self, name):
|
|
return self.dict[string.lower(name)]
|
|
|
|
def has_key(self, name):
|
|
return self.dict.has_key(string.lower(name))
|
|
|
|
def keys(self):
|
|
return self.dict.keys()
|
|
|
|
def values(self):
|
|
return self.dict.values()
|
|
|
|
def items(self):
|
|
return self.dict.items()
|
|
|
|
|
|
|
|
# Utility functions
|
|
# -----------------
|
|
|
|
# XXX Should fix these to be really conformant.
|
|
# XXX The inverses of the parse functions may also be useful.
|
|
|
|
|
|
# Remove quotes from a string.
|
|
|
|
def unquote(str):
|
|
if len(str) > 1:
|
|
if str[0] == '"' and str[-1:] == '"':
|
|
return str[1:-1]
|
|
if str[0] == '<' and str[-1:] == '>':
|
|
return str[1:-1]
|
|
return str
|
|
|
|
|
|
# Parse an address into (name, address) tuple
|
|
|
|
def parseaddr(address):
|
|
# This is probably not perfect
|
|
address = string.strip(address)
|
|
# Case 1: part of the address is in <xx@xx> form.
|
|
pos = regex.search('<.*>', address)
|
|
if pos >= 0:
|
|
name = address[:pos]
|
|
address = address[pos:]
|
|
length = regex.match('<.*>', address)
|
|
name = name + address[length:]
|
|
address = address[:length]
|
|
else:
|
|
# Case 2: part of the address is in (comment) form
|
|
pos = regex.search('(.*)', address)
|
|
if pos >= 0:
|
|
name = address[pos:]
|
|
address = address[:pos]
|
|
length = regex.match('(.*)', name)
|
|
address = address + name[length:]
|
|
name = name[:length]
|
|
else:
|
|
# Case 3: neither. Only an address
|
|
name = ''
|
|
name = string.strip(name)
|
|
address = string.strip(address)
|
|
if address and address[0] == '<' and address[-1] == '>':
|
|
address = address[1:-1]
|
|
if name and name[0] == '(' and name[-1] == ')':
|
|
name = name[1:-1]
|
|
return name, address
|
|
|
|
|
|
# Parse a date field
|
|
|
|
_monthnames = ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul',
|
|
'Aug', 'Sep', 'Oct', 'Nov', 'Dec']
|
|
|
|
def parsedate(data):
|
|
# XXX This still mostly ignores timezone matters at the moment...
|
|
data = string.split(data)
|
|
if data[0][-1] == ',':
|
|
# There's a dayname here. Skip it
|
|
del data[0]
|
|
if len(data) == 4:
|
|
s = data[3]
|
|
i = string.find(s, '+')
|
|
if i > 0:
|
|
data[3:] = [s[:i], s[i+1:]]
|
|
else:
|
|
data.append('') # Dummy tz
|
|
if len(data) < 5:
|
|
return None
|
|
data = data[:5]
|
|
[dd, mm, yy, tm, tz] = data
|
|
if not mm in _monthnames:
|
|
return None
|
|
mm = _monthnames.index(mm)+1
|
|
tm = string.splitfields(tm, ':')
|
|
if len(tm) == 2:
|
|
[thh, tmm] = tm
|
|
tss = '0'
|
|
else:
|
|
[thh, tmm, tss] = tm
|
|
try:
|
|
yy = string.atoi(yy)
|
|
dd = string.atoi(dd)
|
|
thh = string.atoi(thh)
|
|
tmm = string.atoi(tmm)
|
|
tss = string.atoi(tss)
|
|
except string.atoi_error:
|
|
return None
|
|
tuple = (yy, mm, dd, thh, tmm, tss, 0, 0, 0)
|
|
return tuple
|
|
|
|
|
|
# When used as script, run a small test program.
|
|
# The first command line argument must be a filename containing one
|
|
# message in RFC-822 format.
|
|
|
|
if __name__ == '__main__':
|
|
import sys
|
|
file = '/ufs/guido/Mail/drafts/,1'
|
|
if sys.argv[1:]: file = sys.argv[1]
|
|
f = open(file, 'r')
|
|
m = Message(f)
|
|
print 'From:', m.getaddr('from')
|
|
print 'To:', m.getaddrlist('to')
|
|
print 'Subject:', m.getheader('subject')
|
|
print 'Date:', m.getheader('date')
|
|
date = m.getdate('date')
|
|
if date:
|
|
print 'ParsedDate:', time.asctime(date)
|
|
else:
|
|
print 'ParsedDate:', None
|
|
m.rewindbody()
|
|
n = 0
|
|
while f.readline():
|
|
n = n + 1
|
|
print 'Lines:', n
|
|
print '-'*70
|
|
print 'len =', len(m)
|
|
if m.has_key('Date'): print 'Date =', m['Date']
|
|
if m.has_key('X-Nonsense'): pass
|
|
print 'keys =', m.keys()
|
|
print 'values =', m.values()
|
|
print 'items =', m.items()
|
|
|