Send an event, or a sequence of events, with the given smtp and msg options.

Returns a mailer, which is a function invoked with an address or a sequence of addresses and returns a stream. That stream is a function which takes a single event, or a sequence of events, and sends email about them.

(def email (mailer))

This mailer uses the local sendmail.

(changed :state
  (email "xerxes@trioptimum.org" "shodan@trioptimum.org"))

The first argument are SMTP options like :host, :port, :user, :pass, :tls, and :ssl. The second argument is a map of default message options, like :from or :subject.

(def email (mailer {:host "mail.relay"}
                   {:from "riemann@trioptimum.com"}))

If you provide a single map, mailer will split the SMTP options out for you.

(def email (mailer {:host "mail.relay"
                    :user "foo"
                    :pass "bar"
                    :from "riemann@trioptimum.com"}))

smtp-opts and msg-opts are passed to postal. For more documentation, see https://github.com/drewr/postal

By default, riemann uses (subject events) and (body events) to format emails. You can set your own subject or body formatter functions by including :subject or :body in msg-opts. These formatting functions take a sequence of events and return a string.

(def email (mailer {} {:body (fn [events]
                               (apply prn-str events))}))