Email class

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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 very basic SMTP Service which simple excepts Email objects from a SMTP client and response back to the client. No Janus port definitions are shown. For comments about defining Janus ports for the Email class, see the earlier remarks.

Dummy SMTP Server example

emclass:

  • *
  • 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