class EventMachine::Protocols::SmtpClient
Simple SMTP client
@example
email = EM::Protocols::SmtpClient.send( :domain=>"example.com", :host=>'localhost', :port=>25, # optional, defaults 25 :starttls=>true, # use ssl :from=>"sender@example.com", :to=> ["to_1@example.com", "to_2@example.com"], :header=> {"Subject" => "This is a subject line"}, :body=> "This is the body of the email" ) email.callback{ puts 'Email sent!' } email.errback{ |e| puts 'Email failed!' }
Sending generated emails (using Mail)
mail = Mail.new do from 'alice@example.com' to 'bob@example.com' subject 'This is a test email' body 'Hello, world!' end email = EM::P::SmtpClient.send( :domain=>'example.com', :from=>mail.from.first, :to=>mail.to, :message=>mail.to_s )
Attributes
Public Class Methods
# File lib/em/protocols/smtpclient.rb, line 71 def initialize @succeeded = nil @responder = nil @code = nil @msg = nil end
:host => required String
a string containing the IP address or host name of the SMTP server to connect to.
:port => optional
defaults to 25.
:domain => required String
This is passed as the argument to the EHLO command.
:starttls => optional Boolean
If it evaluates true, then the client will initiate STARTTLS with the server, and abort the connection if the negotiation doesn't succeed. TODO, need to be able to pass certificate parameters with this option.
:auth => optional Hash of auth parameters
If not given, then no auth will be attempted. (In that case, the connection will be aborted if the server requires auth.) Specify the hash value :type to determine the auth type, along with additional parameters depending on the type. Currently only :type => :plain is supported. Pass additional parameters :username (String), and :password (either a String or a Proc that will be called at auth-time). @example :auth => {:type=>:plain, :username=>"mickey@disney.com", :password=>"mouse"}
:from => required String
Specifies the sender of the message. Will be passed as the argument to the MAIL FROM. Do NOT enclose the argument in angle-bracket (<>) characters. The connection will abort if the server rejects the value.
:to => required String or Array of Strings
The recipient(s) of the message. Do NOT enclose any of the values in angle-brackets (<>) characters. It's NOT a fatal error if one or more recipients are rejected by the server. (Of course, if ALL of them are, the server will most likely trigger an error when we try to send data.) An array of codes containing the status of each requested recipient is available after the call completes. TODO, we should define an overridable stub that will be called on rejection of a recipient or a sender, giving user code the chance to try again or abort the connection.
One of either :message, :content, or :header and :body is required:
:message => String
A valid RFC2822 Internet Message.
:content => String
Raw data which MUST be in correct SMTP body format, with escaped leading dots and a trailing dot line.
:header => String or Hash of values to be transmitted in the header of the message.
The hash keys are the names of the headers (do NOT append a trailing colon), and the values are strings containing the header values. TODO, support Arrays of header values, which would cause us to send that specific header line more than once. @example :header => {"Subject" => "Bogus", "CC" => "myboss@example.com"}
:body => Optional String or Array of Strings, defaults blank.
This will be passed as the body of the email message. TODO, this needs to be significantly beefed up. As currently written, this requires the caller to properly format the input into CRLF-delimited lines of 7-bit characters in the standard SMTP transmission format. We need to be able to automatically convert binary data, and add correct line-breaks to text data.
:verbose => Optional.
If true, will cause a lot of information (including the server-side of the conversation) to be dumped to $>.
# File lib/em/protocols/smtpclient.rb, line 138 def self.send args={} args[:port] ||= 25 args[:body] ||= "" =begin (I don't think it's possible for EM#connect to throw an exception under normal circumstances, so this original code is stubbed out. A connect-failure will result in the #unbind method being called without calling #connection_completed.) begin EventMachine.connect( args[:host], args[:port], self) {|c| # According to the EM docs, we will get here AFTER post_init is called. c.args = args c.set_comm_inactivity_timeout 60 } rescue # We'll get here on a connect error. This code mimics the effect # of a call to invoke_internal_error. Would be great to DRY this up. # (Actually, it may be that we never get here, if EM#connect catches # its errors internally.) d = EM::DefaultDeferrable.new d.set_deferred_status(:failed, {:error=>[:connect, 500, "unable to connect to server"]}) d end =end EventMachine.connect( args[:host], args[:port], self) {|c| # According to the EM docs, we will get here AFTER post_init is called. c.args = args c.set_comm_inactivity_timeout 60 } end
Public Instance Methods
@private
# File lib/em/protocols/smtpclient.rb, line 178 def connection_completed @responder = :receive_signon @msg = [] end
@private
# File lib/em/protocols/smtpclient.rb, line 172 def post_init @return_values = OpenStruct.new @return_values.start_time = Time.now end
@private
# File lib/em/protocols/smtpclient.rb, line 200 def receive_line ln $>.puts ln if @args[:verbose] @range = ln[0...1].to_i @code = ln[0...3].to_i @msg << ln[4..-1] unless ln[3...4] == '-' $>.puts @responder if @args[:verbose] send @responder @msg.clear end end
We can get here in a variety of ways, all of them being failures unless the @succeeded flag is set. If a protocol success was recorded, then don’t set a deferred success because the caller will already have done it (no need to wait until the connection closes to invoke the callbacks).
@private
# File lib/em/protocols/smtpclient.rb, line 189 def unbind unless @succeeded @return_values.elapsed_time = Time.now - @return_values.start_time @return_values.responder = @responder @return_values.code = @code @return_values.message = @msg set_deferred_status(:failed, @return_values) end end
Private Instance Methods
# File lib/em/protocols/smtpclient.rb, line 335 def escape_leading_dots(s) s.gsub(/^\./, '..') end
Perform an authentication. If the caller didn’t request one, then fall through to the mail-from state.
# File lib/em/protocols/smtpclient.rb, line 282 def invoke_auth if @args[:auth] if @args[:auth][:type] == :plain psw = @args[:auth][:password] if psw.respond_to?(:call) psw = psw.call end #str = Base64::encode64("\0#{@args[:auth][:username]}\0#{psw}").chomp str = ["\0#{@args[:auth][:username]}\0#{psw}"].pack("m").gsub(/\n/, '') send_data "AUTH PLAIN #{str}\r\n" @responder = :receive_auth_response else return invoke_internal_error("unsupported auth type") end else invoke_mail_from end end
# File lib/em/protocols/smtpclient.rb, line 339 def invoke_data send_data "DATA\r\n" @responder = :receive_data_response end
# File lib/em/protocols/smtpclient.rb, line 271 def invoke_ehlo_over_tls send_ehlo @responder = :receive_ehlo_over_tls_response end
We encountered an error from the server and will close the connection. Use the error and message the server returned.
# File lib/em/protocols/smtpclient.rb, line 217 def invoke_error @return_values.elapsed_time = Time.now - @return_values.start_time @return_values.responder = @responder @return_values.code = @code @return_values.message = @msg set_deferred_status :failed, @return_values send_data "QUIT\r\n" close_connection_after_writing end
We encountered an error on our side of the protocol and will close the connection. Use an extra-protocol error code (900) and use the message from the caller.
# File lib/em/protocols/smtpclient.rb, line 230 def invoke_internal_error msg = "???" @return_values.elapsed_time = Time.now - @return_values.start_time @return_values.responder = @responder @return_values.code = 900 @return_values.message = msg set_deferred_status :failed, @return_values send_data "QUIT\r\n" close_connection_after_writing end
# File lib/em/protocols/smtpclient.rb, line 305 def invoke_mail_from send_data "MAIL FROM: <#{@args[:from]}>\r\n" @responder = :receive_mail_from_response end
# File lib/em/protocols/smtpclient.rb, line 314 def invoke_rcpt_to @rcpt_responses ||= [] l = @rcpt_responses.length to = @args[:to].is_a?(Array) ? @args[:to] : [@args[:to].to_s] if l < to.length send_data "RCPT TO: <#{to[l]}>\r\n" @responder = :receive_rcpt_to_response else e = @rcpt_responses.select {|rr| rr.last == 2} if e and e.length > 0 invoke_data else invoke_error end end end
# File lib/em/protocols/smtpclient.rb, line 255 def invoke_starttls if @args[:starttls] # It would be more sociable to first ask if @server_caps contains # the string "STARTTLS" before we invoke it, but hey, life's too short. send_data "STARTTLS\r\n" @responder = :receive_starttls_response else invoke_auth end end
# File lib/em/protocols/smtpclient.rb, line 300 def receive_auth_response return invoke_error unless @range == 2 invoke_mail_from end
# File lib/em/protocols/smtpclient.rb, line 343 def receive_data_response return invoke_error unless @range == 3 # The data to send can be given in either @args[:message], @args[:content], or the # combination of @args[:header] and @args[:body]. # # - @args[:message] (String) MUST be a valid RFC2822 Internet Message # # - @args[:content] (String) MUST be in correct SMTP body format, with escaped # leading dots and a trailing dot line # # - @args[:header] (Hash or String) # - @args[:body] (Array or String) if @args[:message] send_data escape_leading_dots(@args[:message].to_s) send_data "\r\n.\r\n" elsif @args[:content] send_data @args[:content].to_s else # The header can be a hash or an array. if @args[:header].is_a?(Hash) (@args[:header] || {}).each {|k,v| send_data escape_leading_dots("#{k}: #{v}\r\n") } else send_data escape_leading_dots(@args[:header].to_s) end send_data "\r\n" if @args[:body].is_a?(Array) @args[:body].each {|e| send_data escape_leading_dots(e)} else send_data escape_leading_dots(@args[:body].to_s) end send_data "\r\n.\r\n" end @responder = :receive_message_response end
# File lib/em/protocols/smtpclient.rb, line 275 def receive_ehlo_over_tls_response return invoke_error unless @range == 2 invoke_auth end
# File lib/em/protocols/smtpclient.rb, line 249 def receive_ehlo_response return invoke_error unless @range == 2 @server_caps = @msg invoke_starttls end
# File lib/em/protocols/smtpclient.rb, line 309 def receive_mail_from_response return invoke_error unless @range == 2 invoke_rcpt_to end
# File lib/em/protocols/smtpclient.rb, line 381 def receive_message_response return invoke_error unless @range == 2 send_data "QUIT\r\n" close_connection_after_writing @succeeded = true @return_values.elapsed_time = Time.now - @return_values.start_time @return_values.responder = @responder @return_values.code = @code @return_values.message = @msg set_deferred_status :succeeded, @return_values end
# File lib/em/protocols/smtpclient.rb, line 330 def receive_rcpt_to_response @rcpt_responses << [@code, @msg, @range] invoke_rcpt_to end
# File lib/em/protocols/smtpclient.rb, line 244 def receive_signon return invoke_error unless @range == 2 send_ehlo @responder = :receive_ehlo_response end
# File lib/em/protocols/smtpclient.rb, line 265 def receive_starttls_response return invoke_error unless @range == 2 start_tls invoke_ehlo_over_tls end
# File lib/em/protocols/smtpclient.rb, line 240 def send_ehlo send_data "EHLO #{@args[:domain]}\r\n" end