package main

import smtpmock "github.com/mocktools/go-smtp-mock/v2"

smtpmock.ConfigurationAttr{

  // Customizing server behavior
  // ---------------------------------------------------------------------
  // Host address where smtpmock will run, it's equal to "127.0.0.1" by default
  HostAddress:                   "[::]",

  // Port number on which the server will bind. If it not specified, it will be
  // assigned dynamically after server.Start() by default
  PortNumber:                    2525,

  // Enables/disables log to stdout. It's equal to false by default
  LogToStdout:                   true,

  // Enables/disables log server activity. It's equal to false by default
  LogServerActivity:             true,

  // Ability to specify session timeout. It's equal to 30 seconds by default
  SessionTimeout:                42,

  // Ability to specify graceful shutdown timeout. It's equal to 1 second by default
  ShutdownTimeout:               5,


  // Customizing SMTP command handlers behavior
  // ---------------------------------------------------------------------
  // Ability to configure fail fast scenario. It means that server will
  // close client session for case when command was inconsistent or failed.
  // It's equal to false by default
  IsCmdFailFast:                 true,

  // Ability to configure multiple RCPT TO command receiving during one session.
  // It means that server will handle and save all RCPT TO command request-response
  // pairs until receive successful response and next SMTP command has been passed.
  // Please note, by default will be saved only one, the last RCPT TO command
  // request-response pair. It's equal to false by default
  MultipleRcptto:                true,

  // Ability to configure multiple message receiving during one session. It means that server
  // will create another message during current SMTP session in case when RSET
  // command has been used after successful commands chain: MAIL FROM, RCPT TO, DATA.
  // Please note, by default RSET command flushes current message in any case.
  // It's equal to false by default
  MultipleMessageReceiving:      true,

  // Ability to specify blacklisted HELO domains. It's equal to empty []string
  BlacklistedHeloDomains:        []string{"example1.com", "example2.com", "localhost"},

  // Ability to specify blacklisted MAIL FROM emails. It's equal to empty []string
  BlacklistedMailfromEmails:     []string{"[email protected]", "[email protected]"},

  // Ability to specify blacklisted RCPT TO emails. It's equal to empty []string
  BlacklistedRcpttoEmails:       []string{"[email protected]", "[email protected]"},

  // Ability to specify not registered (non-existent) RCPT TO emails.
  // It's equal to empty []string
  NotRegisteredEmails:           []string{"[email protected]", "[email protected]"},

  // Ability to specify HELO response delay in seconds. It runs immediately,
  // equals to 0 seconds by default
  ResponseDelayHelo:             2,

  // Ability to specify MAIL FROM response delay in seconds. It runs immediately,
  // equals to 0 seconds by default
  ResponseDelayMailfrom:         2,

  // Ability to specify RCPT TO response delay in seconds. It runs immediately,
  // equals to 0 seconds by default
  ResponseDelayRcptto:           2,

  // Ability to specify DATA response delay in seconds. It runs immediately,
  // equals to 0 seconds by default
  ResponseDelayData:             2,

  // Ability to specify message response delay in seconds. It runs immediately,
  // equals to 0 seconds by default
  ResponseDelayMessage:          2,

  // Ability to specify RSET response delay in seconds. It runs immediately,
  // equals to 0 seconds by default
  ResponseDelayRset:             2,

  // Ability to specify QUIT response delay in seconds. It runs immediately,
  // equals to 0 seconds by default
  ResponseDelayQuit:             2,

  // Ability to specify message body size limit. It's equal to 10485760 bytes (10MB) by default
  MsgSizeLimit:                  5,


  // Customizing SMTP command handler messages context
  // ---------------------------------------------------------------------
  // Custom server greeting message. Base on defaultGreetingMsg by default
  MsgGreeting:                   "msgGreeting",

  // Custom invalid command message. Based on defaultInvalidCmdMsg by default
  MsgInvalidCmd:                 "msgInvalidCmd",

  // Custom invalid command HELO sequence message.
  // Based on defaultInvalidCmdHeloSequenceMsg by default
  MsgInvalidCmdHeloSequence:     "msgInvalidCmdHeloSequence",

  // Custom invalid command HELO argument message.
  // Based on defaultInvalidCmdHeloArgMsg by default
  MsgInvalidCmdHeloArg:          "msgInvalidCmdHeloArg",

  // Custom HELO blacklisted domain message. Based on defaultQuitMsg by default
  MsgHeloBlacklistedDomain:      "msgHeloBlacklistedDomain",

  // Custom HELO received message. Based on defaultReceivedMsg by default
  MsgHeloReceived:               "msgHeloReceived",

  // Custom invalid command MAIL FROM sequence message.
  // Based on defaultInvalidCmdMailfromSequenceMsg by default
  MsgInvalidCmdMailfromSequence: "msgInvalidCmdMailfromSequence",

  // Custom invalid command MAIL FROM argument message.
  // Based on defaultInvalidCmdMailfromArgMsg by default
  MsgInvalidCmdMailfromArg:      "msgInvalidCmdMailfromArg",

  // Custom MAIL FROM blacklisted email message. Based on defaultQuitMsg by default
  MsgMailfromBlacklistedEmail:   "msgMailfromBlacklistedEmail",

  // Custom MAIL FROM received message. Based on defaultReceivedMsg by default
  MsgMailfromReceived:           "msgMailfromReceived",

  // Custom invalid command RCPT TO sequence message.
  // Based on defaultInvalidCmdRcpttoSequenceMsg by default
  MsgInvalidCmdRcpttoSequence:   "msgInvalidCmdRcpttoSequence",

  // Custom invalid command RCPT TO argument message.
  // Based on defaultInvalidCmdRcpttoArgMsg by default
  MsgInvalidCmdRcpttoArg:        "msgInvalidCmdRcpttoArg",

  // Custom RCPT TO not registered email message.
  // Based on defaultNotRegisteredRcpttoEmailMsg by default
  MsgRcpttoNotRegisteredEmail:   "msgRcpttoNotRegisteredEmail",

  // Custom RCPT TO blacklisted email message. Based on defaultQuitMsg by default
  MsgRcpttoBlacklistedEmail:     "msgRcpttoBlacklistedEmail",

  // Custom RCPT TO received message. Based on defaultReceivedMsg by default
  MsgRcpttoReceived:             "msgRcpttoReceived",

  // Custom invalid command DATA sequence message.
  // Based on defaultInvalidCmdDataSequenceMsg by default
  MsgInvalidCmdDataSequence:     "msgInvalidCmdDataSequence",

  // Custom DATA received message. Based on defaultReadyForReceiveMsg by default
  MsgDataReceived:               "msgDataReceived",

  // Custom size is too big message. Based on defaultMsgSizeIsTooBigMsg by default
  MsgMsgSizeIsTooBig:            "msgMsgSizeIsTooBig",

  // Custom received message body message. Based on defaultReceivedMsg by default
  MsgMsgReceived:                "msgMsgReceived",

  // Custom invalid command RSET sequence message.
  // Based on defaultInvalidCmdHeloSequenceMsg by default
  MsgInvalidCmdRsetSequence:     "msgInvalidCmdRsetSequence",

  // Custom invalid command RSET message. Based on defaultInvalidCmdMsg by default
  MsgInvalidCmdRsetArg:           "msgInvalidCmdRsetArg",

  // Custom RSET received message. Based on defaultOkMsg by default
  MsgRsetReceived:               "msgRsetReceived",

  // Custom quit command message. Based on defaultQuitMsg by default
  MsgQuitCmd:                    "msgQuitCmd",
}

package main

import (
  "fmt"
  "net"
  "net/smtp"

  smtpmock "github.com/mocktools/go-smtp-mock/v2"
)

func main() {
  // You can pass empty smtpmock.ConfigurationAttr{}. It means that smtpmock will use default settings
  server := smtpmock.New(smtpmock.ConfigurationAttr{
    LogToStdout:       true,
    LogServerActivity: true,
  })

  // To start server use Start() method
  if err := server.Start(); err != nil {
    fmt.Println(err)
  }

  // Server's port will be assigned dynamically after server.Start()
  // for case when portNumber wasn't specified
  hostAddress, portNumber := "127.0.0.1", server.PortNumber()

  // Possible SMTP-client stuff for iteration with mock server
  address := fmt.Sprintf("%s:%d", hostAddress, portNumber)
  timeout := time.Duration(2) * time.Second

  connection, _ := net.DialTimeout("tcp", address, timeout)
  client, _ := smtp.NewClient(connection, hostAddress)
  client.Hello("example.com")
  client.Quit()
  client.Close()

  // Each result of SMTP session will be saved as message.
  // To get access to server messages use Messages() method
  server.Messages()

  // To stop the server use Stop() method. Please note, smtpmock uses graceful shutdown.
  // It means that smtpmock will end all sessions after client responses or by session
  // timeouts immediately.
  if err := server.Stop(); err != nil {
    fmt.Println(err)
  }
}