Custom SMTP hooks

SMTP hooks enable extending capabilities of the SMTP server and are run synchronously upon email reception, before the email is enqueued in the MailQueue, and before any mail processing takes place.

Available generic hooks

The following interfaces allows interacting with the following commands:

  • AuthHook: Implement this interfaces to hook in the AUTH Command.

    HookResult doAuth(SMTPSession session, Username username, String password);

  • HeloHook: Implement this interfaces to hook in the HELO Command

    HookResult doHelo(SMTPSession session, String helo);

  • MailHook: Implement this interfaces to hook in the MAIL Command

    HookResult doMail(SMTPSession session, MaybeSender sender);

  • MailParametersHook: Implement this interfaces to hook in the MAIL Command, this is called for specific mail arguments

    HookResult doMailParameter(SMTPSession session, String paramName, String paramValue);

  • QuitHook: Implement this interfaces to hook in the QUIT Command

    HookResult doQuit(SMTPSession session);

  • RcptHook: Implement this interfaces to hook in the RCPT Command

    HookResult doRcpt(SMTPSession session, MaybeSender sender, MailAddress rcpt);

  • UnknownHook: Hook for unknown commands

    HookResult doUnknown(SMTPSession session, String command);

Custom hook registration

Register you hooks using smtpserver.xml handlerchain property.

Writing additional SMTP commands

What to do if the Hook API is not enough for you ?

You want for example to write a code which handles a new command like "YOURCOOLCOMMAND: whatever@example".

For this kind of needs you should implement the CommandHandler interface. This gives you a lower-level API to handle this kind of tasks. If you want to support a custom Hook in your CommandHandler its the best to just extend AbstractHookableCmdHandler.