| """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 string |
| import time |
| |
| |
| _blanklines = ('\r\n', '\n') # Optimization for islast() |
| |
| |
| class Message: |
| """Represents a single RFC-822-compliant message.""" |
| |
| def __init__(self, fp, seekable = 1): |
| """Initialize the class instance and read the headers.""" |
| 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 |
| |
| def rewindbody(self): |
| """Rewind the file to the start of the body (if seekable).""" |
| if not self.seekable: |
| raise IOError, "unseekable file" |
| self.fp.seek(self.startofbody) |
| |
| def readheaders(self): |
| """Read header lines. |
| |
| 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). |
| """ |
| 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 |
| |
| def islast(self, line): |
| """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. |
| """ |
| return line in _blanklines |
| |
| def getallmatchingheaders(self, name): |
| """Find all header lines matching a given header name. |
| |
| 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. |
| """ |
| 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 |
| |
| def getfirstmatchingheader(self, name): |
| """Get the first header line matching name. |
| |
| This is similar to getallmatchingheaders, but it returns |
| only the first matching header (and its continuation |
| lines). |
| """ |
| 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 |
| |
| def getrawheader(self, name): |
| """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. |
| """ |
| |
| list = self.getfirstmatchingheader(name) |
| if not list: |
| return None |
| list[0] = list[0][len(name) + 1:] |
| return string.joinfields(list, '') |
| |
| def getheader(self, name): |
| """Get the header value for a name. |
| |
| This is the normal interface: it return a stripped |
| version of the header value for a given header name, |
| or None if it doesn't exist. This uses the dictionary |
| version which finds the *last* such header. |
| """ |
| try: |
| return self.dict[string.lower(name)] |
| except KeyError: |
| return None |
| |
| def getaddr(self, name): |
| """Get a single address from a header, as a tuple. |
| |
| An example return value: |
| ('Guido van Rossum', 'guido@cwi.nl') |
| """ |
| # New, by Ben Escoto |
| alist = self.getaddrlist(name) |
| if alist: |
| return alist[0] |
| else: |
| return (None, None) |
| |
| def getaddrlist(self, name): |
| """Get a list of addresses from a header. |
| |
| Retrieves a list of addresses from a header, where each |
| address is a tuple as returned by getaddr(). |
| """ |
| # New, by Ben Escoto |
| try: |
| data = self[name] |
| except KeyError: |
| return [] |
| a = AddrlistClass(data) |
| return a.getaddrlist() |
| |
| def getdate(self, name): |
| """Retrieve a date field from a header. |
| |
| Retrieves a date field from the named header, returning |
| a tuple compatible with time.mktime(). |
| """ |
| try: |
| data = self[name] |
| except KeyError: |
| return None |
| return parsedate(data) |
| |
| def getdate_tz(self, name): |
| """Retrieve a date field from a header as a 10-tuple. |
| |
| The first 9 elements make up a tuple compatible with |
| time.mktime(), and the 10th is the offset of the poster's |
| time zone from GMT/UTC. |
| """ |
| try: |
| data = self[name] |
| except KeyError: |
| return None |
| return parsedate_tz(data) |
| |
| |
| # Access as a dictionary (only finds *last* header of each type): |
| |
| def __len__(self): |
| """Get the number of headers in a message.""" |
| return len(self.dict) |
| |
| def __getitem__(self, name): |
| """Get a specific header, as from a dictionary.""" |
| return self.dict[string.lower(name)] |
| |
| def __delitem__(self, name): |
| """Delete all occurrences of a specific header, if it is present.""" |
| name = string.lower(name) |
| if not self.dict.has_key(name): |
| return |
| del self.dict[name] |
| name = name + ':' |
| n = len(name) |
| list = [] |
| hit = 0 |
| for i in range(len(self.headers)): |
| line = self.headers[i] |
| if string.lower(line[:n]) == name: |
| hit = 1 |
| elif line[:1] not in string.whitespace: |
| hit = 0 |
| if hit: |
| list.append(i) |
| list.reverse() |
| for i in list: |
| del self.headers[i] |
| |
| def has_key(self, name): |
| """Determine whether a message contains the named header.""" |
| return self.dict.has_key(string.lower(name)) |
| |
| def keys(self): |
| """Get all of a message's header field names.""" |
| return self.dict.keys() |
| |
| def values(self): |
| """Get all of a message's header field values.""" |
| return self.dict.values() |
| |
| def items(self): |
| """Get all of a message's headers. |
| |
| Returns a list of name, value tuples. |
| """ |
| return self.dict.items() |
| |
| |
| |
| # Utility functions |
| # ----------------- |
| |
| # XXX Should fix unquote() and quote() to be really conformant. |
| # XXX The inverses of the parse functions may also be useful. |
| |
| |
| def unquote(str): |
| """Remove quotes from a string.""" |
| 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 |
| |
| |
| def quote(str): |
| """Add quotes around a string.""" |
| return '"%s"' % string.join( |
| string.split( |
| string.join( |
| string.split(str, '\\'), |
| '\\\\'), |
| '"'), |
| '\\"') |
| |
| |
| def parseaddr(address): |
| """Parse an address into a (realname, mailaddr) tuple.""" |
| a = AddrlistClass(address) |
| list = a.getaddrlist() |
| if not list: |
| return (None, None) |
| else: |
| return list[0] |
| |
| |
| class AddrlistClass: |
| """Address parser class by Ben Escoto. |
| |
| To understand what this class does, it helps to have a copy of |
| RFC-822 in front of you. |
| """ |
| |
| def __init__(self, field): |
| """Initialize a new instance. |
| |
| `field' is an unparsed address header field, containing |
| one or more addresses. |
| """ |
| self.specials = '()<>@,:;.\"[]' |
| self.pos = 0 |
| self.LWS = ' \t' |
| self.CR = '\r' |
| self.atomends = self.specials + self.LWS + self.CR |
| |
| self.field = field |
| self.commentlist = [] |
| |
| def gotonext(self): |
| """Parse up to the start of the next address.""" |
| while self.pos < len(self.field): |
| if self.field[self.pos] in self.LWS + '\n\r': |
| self.pos = self.pos + 1 |
| elif self.field[self.pos] == '(': |
| self.commentlist.append(self.getcomment()) |
| else: break |
| |
| def getaddrlist(self): |
| """Parse all addresses. |
| |
| Returns a list containing all of the addresses. |
| """ |
| ad = self.getaddress() |
| if ad: |
| return ad + self.getaddrlist() |
| else: return [] |
| |
| def getaddress(self): |
| """Parse the next address.""" |
| self.commentlist = [] |
| self.gotonext() |
| |
| oldpos = self.pos |
| oldcl = self.commentlist |
| plist = self.getphraselist() |
| |
| self.gotonext() |
| returnlist = [] |
| |
| if self.pos >= len(self.field): |
| # Bad email address technically, no domain. |
| if plist: |
| returnlist = [(string.join(self.commentlist), plist[0])] |
| |
| elif self.field[self.pos] in '.@': |
| # email address is just an addrspec |
| # this isn't very efficient since we start over |
| self.pos = oldpos |
| self.commentlist = oldcl |
| addrspec = self.getaddrspec() |
| returnlist = [(string.join(self.commentlist), addrspec)] |
| |
| elif self.field[self.pos] == ':': |
| # address is a group |
| returnlist = [] |
| |
| self.pos = self.pos + 1 |
| while self.pos < len(self.field): |
| self.gotonext() |
| if self.field[self.pos] == ';': |
| self.pos = self.pos + 1 |
| break |
| returnlist = returnlist + self.getaddress() |
| |
| elif self.field[self.pos] == '<': |
| # Address is a phrase then a route addr |
| routeaddr = self.getrouteaddr() |
| |
| if self.commentlist: |
| returnlist = [(string.join(plist) + ' (' + \ |
| string.join(self.commentlist) + ')', routeaddr)] |
| else: returnlist = [(string.join(plist), routeaddr)] |
| |
| else: |
| if plist: |
| returnlist = [(string.join(self.commentlist), plist[0])] |
| |
| self.gotonext() |
| if self.pos < len(self.field) and self.field[self.pos] == ',': |
| self.pos = self.pos + 1 |
| return returnlist |
| |
| def getrouteaddr(self): |
| """Parse a route address (Return-path value). |
| |
| This method just skips all the route stuff and returns the addrspec. |
| """ |
| if self.field[self.pos] != '<': |
| return |
| |
| expectroute = 0 |
| self.pos = self.pos + 1 |
| self.gotonext() |
| adlist = None |
| while self.pos < len(self.field): |
| if expectroute: |
| self.getdomain() |
| expectroute = 0 |
| elif self.field[self.pos] == '>': |
| self.pos = self.pos + 1 |
| break |
| elif self.field[self.pos] == '@': |
| self.pos = self.pos + 1 |
| expectroute = 1 |
| elif self.field[self.pos] == ':': |
| self.pos = self.pos + 1 |
| expectaddrspec = 1 |
| else: |
| adlist = self.getaddrspec() |
| self.pos = self.pos + 1 |
| break |
| self.gotonext() |
| |
| return adlist |
| |
| def getaddrspec(self): |
| """Parse an RFC-822 addr-spec.""" |
| aslist = [] |
| |
| self.gotonext() |
| while self.pos < len(self.field): |
| if self.field[self.pos] == '.': |
| aslist.append('.') |
| self.pos = self.pos + 1 |
| elif self.field[self.pos] == '"': |
| aslist.append(self.getquote()) |
| elif self.field[self.pos] in self.atomends: |
| break |
| else: aslist.append(self.getatom()) |
| self.gotonext() |
| |
| if self.pos >= len(self.field) or self.field[self.pos] != '@': |
| return string.join(aslist, '') |
| |
| aslist.append('@') |
| self.pos = self.pos + 1 |
| self.gotonext() |
| return string.join(aslist, '') + self.getdomain() |
| |
| def getdomain(self): |
| """Get the complete domain name from an address.""" |
| sdlist = [] |
| while self.pos < len(self.field): |
| if self.field[self.pos] in self.LWS: |
| self.pos = self.pos + 1 |
| elif self.field[self.pos] == '(': |
| self.commentlist.append(self.getcomment()) |
| elif self.field[self.pos] == '[': |
| sdlist.append(self.getdomainliteral()) |
| elif self.field[self.pos] == '.': |
| self.pos = self.pos + 1 |
| sdlist.append('.') |
| elif self.field[self.pos] in self.atomends: |
| break |
| else: sdlist.append(self.getatom()) |
| |
| return string.join(sdlist, '') |
| |
| def getdelimited(self, beginchar, endchars, allowcomments = 1): |
| """Parse a header fragment delimited by special characters. |
| |
| `beginchar' is the start character for the fragment. |
| If self is not looking at an instance of `beginchar' then |
| getdelimited returns the empty string. |
| |
| `endchars' is a sequence of allowable end-delimiting characters. |
| Parsing stops when one of these is encountered. |
| |
| If `allowcomments' is non-zero, embedded RFC-822 comments |
| are allowed within the parsed fragment. |
| """ |
| if self.field[self.pos] != beginchar: |
| return '' |
| |
| slist = [''] |
| quote = 0 |
| self.pos = self.pos + 1 |
| while self.pos < len(self.field): |
| if quote == 1: |
| slist.append(self.field[self.pos]) |
| quote = 0 |
| elif self.field[self.pos] in endchars: |
| self.pos = self.pos + 1 |
| break |
| elif allowcomments and self.field[self.pos] == '(': |
| slist.append(self.getcomment()) |
| elif self.field[self.pos] == '\\': |
| quote = 1 |
| else: |
| slist.append(self.field[self.pos]) |
| self.pos = self.pos + 1 |
| |
| return string.join(slist, '') |
| |
| def getquote(self): |
| """Get a quote-delimited fragment from self's field.""" |
| return self.getdelimited('"', '"\r', 0) |
| |
| def getcomment(self): |
| """Get a parenthesis-delimited fragment from self's field.""" |
| return self.getdelimited('(', ')\r', 1) |
| |
| def getdomainliteral(self): |
| """Parse an RFC-822 domain-literal.""" |
| return self.getdelimited('[', ']\r', 0) |
| |
| def getatom(self): |
| """Parse an RFC-822 atom.""" |
| atomlist = [''] |
| |
| while self.pos < len(self.field): |
| if self.field[self.pos] in self.atomends: |
| break |
| else: atomlist.append(self.field[self.pos]) |
| self.pos = self.pos + 1 |
| |
| return string.join(atomlist, '') |
| |
| def getphraselist(self): |
| """Parse a sequence of RFC-822 phrases. |
| |
| A phrase is a sequence of words, which are in turn either |
| RFC-822 atoms or quoted-strings. |
| """ |
| plist = [] |
| |
| while self.pos < len(self.field): |
| if self.field[self.pos] in self.LWS: |
| self.pos = self.pos + 1 |
| elif self.field[self.pos] == '"': |
| plist.append(self.getquote()) |
| elif self.field[self.pos] == '(': |
| self.commentlist.append(self.getcomment()) |
| elif self.field[self.pos] in self.atomends: |
| break |
| else: plist.append(self.getatom()) |
| |
| return plist |
| |
| |
| # Parse a date field |
| |
| _monthnames = ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', |
| 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'] |
| _daynames = ['Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat', 'Sun'] |
| |
| # The timezone table does not include the military time zones defined |
| # in RFC822, other than Z. According to RFC1123, the description in |
| # RFC822 gets the signs wrong, so we can't rely on any such time |
| # zones. RFC1123 recommends that numeric timezone indicators be used |
| # instead of timezone names. |
| |
| _timezones = {'UT':0, 'UTC':0, 'GMT':0, 'Z':0, |
| 'AST': -400, 'ADT': -300, # Atlantic standard |
| 'EST': -500, 'EDT': -400, # Eastern |
| 'CST': -600, 'CDT':-500, # Centreal |
| 'MST':-700, 'MDT':-600, # Mountain |
| 'PST':-800, 'PDT':-700 # Pacific |
| } |
| |
| |
| def parsedate_tz(data): |
| """Convert a date string to a time tuple. |
| |
| Accounts for military timezones. |
| """ |
| data = string.split(data) |
| if data[0][-1] == ',' or data[0] in _daynames: |
| # There's a dayname here. Skip it |
| del data[0] |
| if len(data) == 3: # RFC 850 date, deprecated |
| stuff = string.split(data[0], '-') |
| if len(stuff) == 3: |
| data = stuff + data[1:] |
| 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: |
| dd, mm, yy, tm, tz = mm, dd, tm, yy, tz |
| 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 |
| tzoffset=None |
| tz=string.upper(tz) |
| if _timezones.has_key(tz): |
| tzoffset=_timezones[tz] |
| else: |
| try: |
| tzoffset=string.atoi(tz) |
| except string.atoi_error: |
| pass |
| # Convert a timezone offset into seconds ; -0500 -> -18000 |
| if tzoffset: |
| if tzoffset < 0: |
| tzsign = -1 |
| tzoffset = -tzoffset |
| else: |
| tzsign = 1 |
| tzoffset = tzsign * ( (tzoffset/100)*3600 + (tzoffset % 100)*60) |
| tuple = (yy, mm, dd, thh, tmm, tss, 0, 0, 0, tzoffset) |
| return tuple |
| |
| |
| def parsedate(data): |
| """Convert a time string to a time tuple.""" |
| t=parsedate_tz(data) |
| if type(t)==type( () ): |
| return t[:9] |
| else: return t |
| |
| |
| def mktime_tz(data): |
| """Turn a 10-tuple as returned by parsedate_tz() into a UTC timestamp. |
| |
| Minor glitch: this first interprets the first 8 elements as a |
| local time and then compensates for the timezone difference; |
| this may yield a slight error around daylight savings time |
| switch dates. Not enough to worry about for common use. |
| |
| """ |
| if data[9] is None: |
| # No zone info, so localtime is better assumption than GMT |
| return time.mktime(data[:8] + (-1,)) |
| else: |
| t = time.mktime(data[:8] + (0,)) |
| return t - data[9] - time.timezone |
| |
| |
| # 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, os |
| file = os.path.join(os.environ['HOME'], 'Mail/inbox/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_tz('date') |
| if date: |
| print 'ParsedDate:', time.asctime(date[:-1]), |
| hhmmss = date[-1] |
| hhmm, ss = divmod(hhmmss, 60) |
| hh, mm = divmod(hhmm, 60) |
| print "%+03d%02d" % (hh, mm), |
| if ss: print ".%02d" % ss, |
| print |
| 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() |