Email class

The Email class is a high level, object oriented interface to client sockets that lets you write a SOUL SMTP (Simple Mail Transfer Protocol) request without knowledge of socket level programming or the format of SMTP requests and responses.

The Email class methods let a SOUL program act as an SMTP client. SMTP clients send mail requests to an SMTP server, not directly to other SMTP clients. The Email class methods only support communication with SMTP servers.

An SMTP server will "store and forward" mail it receives. This means that all messages are first received in entirety on the SMTP server, then the server attempts to deliver it to the recipients. Mail delivery can be delayed by a server that is down or too busy to accept connections. "Store and forward" gives the SMTP server the ability to retry delivery without making the SMTP client wait for completion.

A server might try to deliver a message for as long as a week or more. This, of course, makes it impractical for a client to wait for delivery confirmation, so the SMTP protocol does not provide such information. A "success" response from an SMTP server indicates only that the server has accepted the request and will attempt to deliver the mail to the recipients.

Most SMTP servers will at least confirm that any domain names in the recipient list are valid, but they cannot confirm that an actual recipient name is valid.

You must define a Janus CLSOCK port to use the Email class. If you supply the IP address of the server and the port number in the port definition, SMTP applications need only know the Janus port name to communicate with the server. The following example defines a client socket port for use by SMTP applications. For more detailed information about defining Janus client socket ports, see JANUS DEFINE and JANUS CLSOCK.

JANUS DEFINE MYSMTP * CLSOCK 5 REMOTE 198.242.244.100 25

Note: To use Email objects under versions of Model 204 earlier than 7.5, you must have licensed Janus TCP/IP Base, Janus Sockets, and Janus SOAP. Under version 7.5 and later, you do not require Janus SOAP.

For information about using SOUL objects, see Object oriented programming in SOUL and Getting started with OOP for User Language programmers.

Email class summary

The following capabilities are provided by the Email class:

• Creating general purpose e-mail for SMTP
• Sending general purpose e-mail via SMTP
• Setting e-mail content using Longstrings
• Sending MIME content (attachments and alternative content)
• Sending to multiple recipients
• Access to status (error or confirmation messages)

You use the Email object to generate SMTP messages (e-mail) to send to an SMTP server. To construct a request, you use Email methods to set and inspect header information, content, and attachments. To send e-mail, you use the Mail method.

List of Email methods contains a list of all the methods in the Email class.

Dummy SMTP Server example

This is an example of a very basic SMTP Server: it simply accepts Email objects from an SMTP client, and in turn, sends a response. It does not store or retrieve messages.

No Janus port definitions are shown. For comments about defining Janus ports for the Email class, see the earlier remarks.

Dummy SMTP Server

emclass.ul:

***********************************************************************
*                                                                     *
* encoding enumerations.                                              *
*                                                                     *
***********************************************************************
enumeration encoding
   public
   value base64
   value none
   end  public
end enumeration
 
***********************************************************************
*                                                                     *
* emailPart class.                                                    *
*                                                                     *
***********************************************************************
class emailPart
 
public
   variable headers is object stringlist
   variable body is object stringlist
   function type is string len 255
   function encoding is string len 255
   function name is string len 255
   function contentlist is object stringlist
   function content is longstring
end public
 
***********************************************************************
*                                                                     *
* Return complete contentlist from an emailPart                       *
*                                                                     *
***********************************************************************
function contentlist is object stringlist
 
return %this:body
 
end function
 
***********************************************************************
*                                                                     *
* Decode and return content from an emailPart                         *
*                                                                     *
***********************************************************************
function content is longstring
 
%toke is object stringTokenizer
%token is string len 128
%encoding is string len 128
%lf   is string len 1
%i    is float
%j    is float
%content is longstring
%concat  is boolean initial(True)
%temp    is longstring
 
if %this:body eq null then return ''; end if
 
%lf = '0A':x
 
for %i from %i + 1 to %this:body:count
   if %this:encoding eq 'base64' then
      %content = %content with %this:body(%i)
   elseif %this:encoding eq 'quoted-printable' then
      %temp = %this:body(%i):Unspace(Leading=False, Trailing=True, -
         Compress=False)
      if %concat = False then
         %content = %content %lf
      end if
      for %j from 1 to %temp:Length - 2
         if %temp:Substring(%j, 1) = '=' then
            %content = %content %temp:Substring(%j + 1, 2): -
            HexToString:AsciiToEbcdic(characterEncode=true)
            %j = %j + 2
         else
            %content = %content %temp:Substring(%j, 1)
         end if
      end for
      if %j <= %temp:Length then
         for %j from %j to %temp:Length
            %content = %content %temp:Substring(%j, 1)
         end for
      end if
      if %content:Right(1) = '=' then
         %concat = True
         %content = %content:TrimRight(1)
      else
         %concat = False
      end if
   else
      %content = %content %this:body(%i) with %lf
   end if
end for
 
if %this:encoding eq 'base64' then
   %content = %content:base64ToString
   if %this:type:left(5) = 'text/' then
      %content = %content:AsciiToEbcdic(CharacterEncode=true)
   end if
end if
 
return %content
 
end function
***********************************************************************
*                                                                     *
* Return the name (if present) of an emailPart                        *
*                                                                     *
***********************************************************************
function name is string len 255
 
%type is string len 255
%name is string len 255
%temp is string len 255
%i    is float
%n    is float
 
for %i from 1 to %this:headers:count
   %temp = %this:headers(%i)
   if 'Content-Disposition:':toUpper eq %temp:word(1):toUpper then
      for %i from %i + 1 to %this:headers:count
         if %temp:word(1):right(1) eq ':' then loop end; end if
         %temp = %temp %this:headers(%i)
      end for
      %i = %i - 1
      %n = %temp:positionOf(' filename=')
      if %n gt 0 then
         %name = %temp:subString(%n)
      end if
      loop end;
   end if
   if 'Content-Type:':toUpper eq %temp:word(1):toUpper then
      for %i from %i + 1 to %this:headers:count
         if %temp:word(1):right(1) eq ':' then loop end; end if
         %temp = %temp %this:headers(%i)
      end for
      %i = %i - 1
      %n = %temp:positionOf(' name=')
      if %n gt 0 then
         %name = %temp:subString(%n)
      end if
   end if
end for
 
%name = %name:word(2, spaces=' =')
if %name:left(1) = '"' then %name = %name:trimLeft(1); end if
if %name:right(1) = '"' then %name = %name:trimRight(1); end if
 
return %name
 
end function
 
***********************************************************************
*                                                                     *
* Return the encoding (if present) of an emailPart                    *
*                                                                     *
***********************************************************************
function encoding is string len 255
 
%enc  is string len 255
%temp is string len 255
%i    is float
%n    is float
 
for %i from 1 to %this:headers:count
   %temp = %this:headers(%i)
   if 'Content-Transfer-Encoding:':toUpper eq %temp:word(1):toUpper then
      for %i from %i + 1 to %this:headers:count
         if %this:headers(%i):word(1):right(1) eq ':' then loop end; end if
         %temp = %temp %this:headers(%i)
      end for
      loop end;
   end if
end for
 
if 'Content-Transfer-Encoding:':toUpper eq %temp:word(1):toUpper then
   %enc = %temp:word(2)
   if %enc:left(1) = '"' then %enc = %enc:trimLeft(1); end if
   if %enc:right(1) = '"' then %enc = %enc:trimRight(1); end if
end if
 
if %enc = '' then %enc = '7bit'; end if
 
return %enc
 
end function
 
***********************************************************************
*                                                                     *
* Return the content type of an emailPart                             *
*                                                                     *
***********************************************************************
function type is string len 255
 
%type is string len 255
%temp is string len 255
%i    is float
%n    is float
 
for %i from 1 to %this:headers:count
   %temp = %this:headers(%i)
   if 'Content-Type:':toUpper eq %temp:word(1):toUpper then
      for %i from %i + 1 to %this:headers:count
         if %temp:word(1):right(1) eq ':' then loop end; end if
         %temp = %temp %this:headers(%i)
      end for
      %i = %i - 1
      loop end;
   end if
end for
 
%type = %temp:word(2)
if %type:left(1) = '"' then %type = %type:trimLeft(1); end if
if %type:right(1) = '"' then %type = %type:trimRight(1); end if
 
if %type = '' then %type = 'text/plain'; end if
 
return %type
 
end function
 
end class
 
***********************************************************************
*                                                                     *
* receivedEmail class.                                                *
*                                                                     *
***********************************************************************
class receivedEmail
 
public
  variable headers is object stringlist
  variable body is object stringlist
  variable rcptList is object stringlist
  variable fromHost is string len 128
  variable from     is string len 128
 
  function header -
    (%name is string len 255, %occur is float default(1)) -
     is string len 255
  function contentList (%x is float) is object stringlist
  function part (%number is float) is object emailPart
  function parts is float
end public
 
***********************************************************************
*                                                                     *
* Return a header from the email message                              *
*                                                                     *
***********************************************************************
function header -
   (%name is string len 255, %occur is float default(1)) -
   is string len 255
 
%i is float
%toke is object stringTokenizer
%token is string len 255
 
for %i from 1 to %this:headers:count
   %toke  = %this:headers(%i):stringTokenizer
   %token = %toke:nextToken:toUpper
   %toke:discard
   if %name:toUpper eq %token then loop end; end if
end for
 
if %i > %this:headers:count then return ''; end if
 
%token = %this:headers(%i)
if %this:headers(%i):right(1) ne ';' then return %token; end if
 
for %i from %i + 1 to %this:headers:count
   %token = %token %this:headers(%i)
   if %this:headers(%i):right(1) ne ';' then loop end; end if
end for
 
return %token
 
end function
 
***********************************************************************
*                                                                     *
* Return a "part" of an email message as an emailPart object.         *
*                                                                     *
***********************************************************************
function part (%number is float) is object emailPart
 
%i is float
%n is float
%bound is string len 72
%part  is object emailPart
%encoding is string len 255
%partNumber is float
%cont is boolean initial(false)
%mime is boolean initial(false)
%temp is string len 255
 
%part = new
%part:headers = new
 
* Scan global headers for boundary
for %i from 1 to %this:headers:count
   %temp = %this:headers(%i)
   if 'Content-Type:':toUpper eq %temp:word(1):toUpper then
      for %i from %i + 1 to %this:headers:count
         if %this:headers(%i):word(1):right(1) eq ':' then loop end; end if
         %temp = %temp %this:headers(%i)
      end for
      %n = %temp:positionOf('boundary=')
      if %n gt 0 then
         %bound = %temp:subString(%n)
      end if
      loop end;
   end if
end for
 
%part:headers = new
%part:body = new
 
if %bound ne '' then
   %bound = %bound:substring(10)
   if %bound:left(1) = '"' then %bound = %bound:trimLeft(1); end if
   if %bound:right(1) = '"' then %bound = %bound:trimRight(1); end if
   %bound = '--' %bound;
   for %i from 1 to %this:body:count
      if %bound = %this:body(%i) then
         %partNumber = %partNumber + 1
         if %partNumber = %number then loop end; end if
      end if
   end for
   for %i from %i + 1 to %this:body:count
      if %this:body(%i) eq '' then loop end; end if
      %part:headers:add(%this:body(%i))
   end for
   for %i from %i + 1 to %this:body:count
      if %bound = %this:body(%i):substring(1, %bound:length) then
         loop end;
      end if
      %part:body:add(%this:body(%i))
   end for
else
   assert %number eq 1
   for %i from 1 to %this:headers:count
      %temp = %this:headers(%i)
      if 'Content-':toUpper eq %temp:word(1):left(8):toUpper then
         %part:headers:add(%temp)
         for %i from %i + 1 to %this:headers:count
            if %this:headers(%i):word(1):right(1) eq ':' then loop end; end if
            %part:headers:add(%this:headers(%i))
         end for
         %i = %i - 1
      end if
   end for
   for %i from 1 to %this:body:count
     %part:body:add(%this:body(%i))
   end for
end if
 
return %part
 
end function
 
***********************************************************************
*                                                                     *
* Return number of "parts" of an email message.                       *
*                                                                     *
***********************************************************************
function parts is float
 
%i is float
%n is float
%bound is string len 128
%parts is float
%temp  is longstring
 
* Scan global headers for boundary
for %i from 1 to %this:headers:count
   %temp = %this:headers(%i)
   if 'Content-Type:':toUpper eq %temp:word(1):toUpper then
      for %i from %i + 1 to %this:headers:count
         if %this:headers(%i):word(1):right(1) eq ':' then loop end; end if
         %temp = %temp %this:headers(%i)
      end for
      %n = %temp:positionOf('boundary=')
      if %n gt 0 then
         %bound = %temp:subString(%n)
      end if
      loop end;
   end if
end for
 
if %bound ne '' then
   %bound = %bound:substring(10)
   if %bound:left(1) = '"' then %bound = %bound:trimLeft(1); end if
   if %bound:right(1) = '"' then %bound = %bound:trimRight(1); end if
   %bound = '--' %bound;
else
   return 1
end if
 
%parts = 0
for %i from 1 to %this:body:count
   if %bound = %this:body(%i) then
      %parts = %parts + 1
   end if
end for
 
return %parts
 
end function
 
end class
***********************************************************************
*                                                                     *
* smtpDriver class.                                                   *
*                                                                     *
***********************************************************************
class smtpDriver
    public shared
       subroutine -
       run(%processEmail is subroutine (receivedEmail):whatever)
    end public shared
 
   subroutine run(%processEmail is subroutine (receivedEmail):whatever)
 
      %receivedEmail is object receivedEmail
 
      *****************************************************************
      * SMTP server program.                                          *
      *****************************************************************
 
      *****************************************************************
      * Static values used by the server.                             *
      *****************************************************************
 
      %serverId         is string len 80 initial -
            ("host.sirius-software.com running Model 204 SMTP server")
 
      *****************************************************************
      * End of static values used by the server.                      *
      *****************************************************************
 
      local subroutine (stringList):audit
      %i  is float
      for %i from 1 to %this:count
         auditText {%i}: {%this(%i)}
      end for
      end subroutine
 
      %remail                 is object receivedEmail
 
      %msg                    is string len 128
      %client                 is string len 128
      %command                is string len 16
      %email                  is object receivedEmail
      %esmtp                  is boolean initial(false)
      %from                   is string len 128
      %by                     is string len 128
      %received               is string len 255
      %dateTime               is string len 128
      %inputLength            is float
      %inputLine              is longstring
      %sock                   is object socket
      %toke                   is object stringTokenizer
      %token                  is string len 128
 
      %sock = serverSocket
 
      %sock:set('CHAR', 'CHAR')
      %sock:set('LINEND', '0D0A')
      %sock:set('PRSTOK', '0D0A')
 
      %dateTime = -
         %(system):currentTimeString('DD Mon YYYY HH:MI:SS')
      %sock:sendWithLineEnd( -
         "220 " with %serverId with " on " with %dateTime)
 
      %inputLength = %sock:receiveAndParse(%inputLine)
 
      %toke = %inputLine:stringTokenizer
 
      %command = %toke:nextToken:toUpper
      if %command eq 'EHLO' then
         %esmtp = true
      elseIf %command ne 'HELO' then
         auditText *** Incorrect hello message received, -
            command={%command}, closing connection
         %sock:close
         stop
      end if
 
      %client = %toke:nextToken
      %msg = "250 Hello " with %client with -
         " I'm delighted to meet you"
      %sock:sendWithLineEnd(%msg)
 
      auditText **** Entering main SMTP loop for {%client}
      repeat forever
         %inputLength = %sock:receiveAndParse(%inputLine)
         %toke = %inputLine:stringTokenizer
         %command = %toke:nextToken:toUpper
         if %command eq 'QUIT' then jump to quit; end if
         if %command ne 'MAIL' then
            auditText **** Unexpected command {%command} received, -
               terminating connection
            jump to close
         end if
         %token = %toke:nextToken
         if %token:left(5):toUpper ne 'FROM:' then
            auditText **** MAIL followed by {%token} not -
               FROM:<email-address>, terminating connection
            jump to close
         end if
         %from = %token:substring(6)
         %sock:sendWithLineEnd("250 Ok")
 
         %email = new
         %email:rcptList = new
 
         %toke = %sock:info('REMOTE'):stringTokenizer
         %email:fromHost = %toke:nextToken
 
         repeat forever
            %inputLength = %sock:receiveAndParse(%inputLine)
            %toke = %inputLine:stringTokenizer
            %command = %toke:nextToken:toUpper
            if %command eq 'QUIT' then jump to quit; end if
            if %command ne 'RCPT' then loop end; end if
            %token = %toke:nextToken
            if %token:left(3):toUpper ne 'TO:' then
               auditText **** RCPT followed by {%token} not -
                  TO:<email-address>, terminating connection
               jump to close
            end if
            %email:rcptList:add(%token:substring(4))
            %sock:sendWithLineEnd("250 Ok")
         end repeat
 
         if %email:rcptList:count eq 0 then
            auditText **** No RCPT TO:s received after a -
               MAIL FROM:, terminating connection
            jump to close
         end if
 
         if %command ne 'DATA' then
            auditText **** No DATA received after a RCPT TO:, -
               terminating connection
            jump to close
         end if
         %sock:sendWithLineEnd("354 End data with a single '.'")
 
         %email:headers = new
         setText %received = Received: from {%email:fromHost} by -
            {%serverid} ; -
            {%(system):currentTimeString('Wkd, DD Mon YYYY HH:MI:SS')}
         %email:headers:add(%received)
 
         repeat forever
            %inputLength = %sock:receiveAndParse(%inputLine)
            if %inputLine = '' then loop end; end if
            if %inputLine eq '.' then loop end; end if
            if %inputLine:left(2) eq '..' then
               %inputLine = %inputLine:substring(2);
            end if
            %email:headers:add(%inputLine)
         end repeat
 
         %email:body = new
         repeat forever
            %inputLength = %sock:receiveAndParse(%inputLine)
            if %inputLine eq '.' then loop end; end if
            if %inputLine:left(2) eq '..' then
               %inputLine = %inputLine:substring(2);
            end if
            %email:body:add(%inputLine)
         end repeat
 
         %sock:sendWithLineEnd("250 E-mail received")
      end repeat
 
 
      quit:
 
      auditText **** QUIT received
      %sock:sendWithLineEnd("221 Bye")
 
      close:
 
      auditText **** Terminating SMTP connection
      %sock:close
 
      %email:%processEmail
 
    end subroutine
 
end class

driver.ul:

UTABLE LNTBL 128
b
 
i emclass.ul
 
local subroutine (receivedEmail):process
 
%i     is float
%j     is float
%x     is float
%ls    is longstring
%op    is string len 8
%temp  is string len 255
%ename is string len 255
%part  is object emailPart
%tp    is float
 
%tp = 0
setText %ename = CSURF_EMAIL_{$sir_date('YYMMDDHHMISS')}
%x = $bldproc(%tp, %ename, 'OPEN')
assert %x eq 0
*
* Get attachments and copy content to output procedure
*
%op = 'APPEND'
for %i from 1 to %this:parts
   %part = %this:part(%i)
   for %j from 1 to %part:headers:count
      %temp = %part:headers(%j):left(255)
      %x = $bldproc(%tp, %temp, %op)
      assert %x eq 0
   end for
   for %j from 1 to %part:body:count
      %temp = %part:body(%j):left(255)
      %x = $bldproc(%tp, %temp, %op)
      assert %x eq 0
   end for
end for
 
end subroutine
 
%(smtpDriver):run(process)
 
end
USE Fred
DISPLAY PROCEDURE 0

SMTP examples

Examples follow in which Email objects are used to create and send a request to an SMTP server. No Janus port definitions are shown. For comments about defining Janus ports for the Email class, see the earlier remarks.

Basic e-mail example

This example uses most of the Email methods to send a simple message to three recipients. The local CLSOCK port used is named SPAM.

b %letter object Email %h longstring %t longstring %name longstring %nick string len 64 %letter = new %name = 'C_Coolidge@presidents.usa' %nick = 'SilentCal' %letter:AddRecipient(%name, %nick) %name = 'D_Eisenhower@presidents.usa' %nick = 'Ike' %letter:AddCc(%name, %nick) %name = L_Johnson@presidents.usa' %nick = 'LBJ' %letter:AddBcc(%name, %nick) %letter:Sender('a_huckster@bankandtrustme.com') %h = 'Subject:' %t = 'Lower Mortgage Rates' %letter:AddHeader(%h, %t) %h = 'Great deal of debt for you!' %letter:SetBody(%h) %letter:mail('SPAM', 0) print %letter:GetReplyCode with ' - ' with - %letter:GetReplyText %letter:discard end

E-mail with attachment

In the following example, an image is attached to a short e-mail message. The attachment is produced from a member of a local Model 204 procedure file using Stringlist class methods.

b %rolex is object Email %sl is object Stringlist %procdata is object Stringlist %jpg longstring %t longstring %temp string len 255 %procfile string len 10 %procname string len 63 %q float %rc float %rolex = new %sl = new %t = 'jbgood@netscape.net' %rolex:AddRecipient(%t, 'JB') %t = 'cberry@ucantbee-sirius.com' %rolex:Sender(%t) %rolex:AddHeader('Subject:', 'watch this...') text to %sl I want an authentic imitation Rolex watch. Something like the one shown in this image. Know anyone who's got one? end text %rolex:SetBody(%sl, encoding='none', type='text/plain') %procfile = 'MYPROC' %procname = 'FAKE5.JPG' %rc = $procopn(%procname, %procfile) if %rc ne 0 then print 'Cant open procedure ' with %procname - with ' in file ' with %procfile with ', rc = ' - with %rc stop end if %procdata = new %procdata:appendOpenProcedure %jpg = %procData:binaryProcedureDecode %rolex:AddPart(%jpg, type='image/jpg', name='Rolex1.jpg') print %rolex:mail('MYSMTP', 0) ' is return from Mail method' print %rolex:GetReplyCode ' is return from GetReplyCode' print %rolex:GetReplyText %rolex:discard end

If the request is successful, results like the following display at the terminal:

0 is return from Mail method 221 is return from GetReplyCode ucantbee-sirius.com running IBM VM SMTP Level 320 closing connection

List of Email methods

The "List of Email methods" shows all the class methods.

See also

• Janus Sockets User Language coding considerations
• Sample Janus Sockets programs
• Socket-level interfaces:
  • $functions
  • Socket class
• Higher-level interfaces:
  • Email class
  • HTTP Helper classes
  • LDAP class
  • Janus FTP Server
  • Janus Telnet Server