smtp

> (define a-mail
    (make-mail "a test email"
               "this is the message body of the test mail"
               #:from "sender1@qq.com"
               #:to '("recipient1@qq.com")
               #:cc '("recipient2@qq.com")
               #:bcc '("recipient3@qq.com" "recipient4@qq.com")
               #:attached-files '("~/abc.txt")))

> (define b-mail
    (make-mail "a test1 email"
               "this is the message body of the test1 mail"
               #:from "sender1@qq.com"
               #:to '("recipient1@qq.com")))

> (define c-mail
    (make-mail "a test2 email"
               "this is the message body of the test2 mail"
               #:from "sender2@qq.com"
               #:to '("recipient1@qq.com")))

> (send-smtp-mail a-mail)

> (send-smtp-mail b-mail)

> (send-smtp-mail c-mail)

1.2 Sending authenticated Emails by dynamically binding some parameters:🔗ℹ

> (parameterize ([current-smtp-username "sender2"]
[current-smtp-password "password2"])
(send-smtp-mail c-mail))

1.3 Sending and authenticating Emails through function arguments:🔗ℹ

> (send-smtp-mail c-mail
                  #:host "smtp.qq.com"
                  #:port 25
                  #:username "sender2"
                  #:password "password2")

1.4 Sending html message:🔗ℹ

> (current-smtp-body-content-type "text/html")

> (define d-mail
     (make-mail "a test of html email"
                "<html><body> <h1>a test of html email</h1> <p>hello world!</p>"
                #:body-content-type "text/html"
                #:from "sender2@qq.com"
                #:to '("recipient1@qq.com")))

> (send-smtp-mail d-mail
                  #:host "smtp.qq.com"
                  #:port 25
                  #:username "sender2"
                  #:password "password2")

1.5 Sending html message with embedding pictures:🔗ℹ

Since most nowadays modern browsers have already supported the Data URLs, we can just directly embed our pictures in the html content and send it:

> (define f-mail
     (make-mail "a test of html email"
     "<html>\n   <body>\n   <div>\n   <p>Taken from wikpedia</p>\n   <img src=\"data:image/png;base64, iVBORw0KGgoAAAANSUhEUgAAAAUA AAAFCAYAAACNbyblAAAAHElEQVQI12P4//8/w38GIAXDIBKE0DHxgljNBAAO 9TXL0Y4OHwAAAABJRU5ErkJggg==\"\n   alt=\"Red dot\" />\n   </div>\n   </body>\n   </html>"








                #:body-content-type "text/html"
                #:from "sender2@qq.com"
                #:to '("recipient1@qq.com")))

> (send-smtp-mail f-mail
                  #:host "smtp.qq.com"
                  #:port 25
                  #:username "sender2"
                  #:password "password2")

2 API🔗ℹ

2.1 Parameters🔗ℹ

Check basic info at Racket Parameters.

parameter
(current-smtp-host) → string?
(current-smtp-host v) → void?
  v : string?
= ""
parameter
(current-smtp-port) → integer?
(current-smtp-port v) → void?
  v : integer?
= 25
parameter
(current-smtp-username) → string?
(current-smtp-username v) → void?
  v : string?
= ""
parameter
(current-smtp-password) → string?
(current-smtp-password v) → void?
  v : string?
= ""

set authentication to be used for sending Emails later, check usage example at Sending Emails authenticated by Parameters:.

parameter
(current-smtp-body-content-type) → string?
(current-smtp-body-content-type v) → void?
v : string?
= "text/plain"

current-smtp-body-content-type is used for set smtp mail body’s content type, check usage example at Sending html message:.

parameter
(current-smtp-debug-mode) → boolean?
(current-smtp-debug-mode v) → void?
v : boolean?
= #f

current-smtp-debug-mode is used for show status of the smtp auth debug mode or set to show or not show the smtp auth log.

2.2 Making and sending mails🔗ℹ

procedure
(make-mail subject
message-body
[ #:from from]
#:to to
[ #:cc cc
#:bcc bcc
#:attached-files attached-files
#:body-content-type body-content-type]) → mail?
  subject : string?
  message-body : string?
  from : string? = (current-smtp-username)
  to : (listof string?)
  cc : (listof string?) = '()
  bcc : (listof string?) = '()
  attached-files : (listof (or/c path? string?)) = '()
  body-content-type : string? = (current-smtp-body-content-type)

Make mail struct instances, check usage example at Sending Emails authenticated by Parameters:.

procedure
(send-smtp-mail email
[ #:host host
#:port port
#:tls-encode tls-encode
#:user username
#:password password]) → void?
  email : mail?
  host : string? = (current-smtp-host)
  port : integer? = (current-smtp-port)
  tls-encode : boolean? = #f
  username : string? = (current-smtp-username)
  password : string? = (current-smtp-password)

Commit the email sending action, check usage example at Sending and authenticating Emails through function arguments:.

2.3 Basis Structs🔗ℹ

struct
(struct mail ( sender
recipients
cc-recipients
bcc-recipients
subject
message-body
attached-files))
  sender : string?
  recipients : list?
  cc-recipients : list?
  bcc-recipients : list?
  subject : string?
  message-body : string?
  attached-files : list?

Structure of smtp mails.

procedure
(mail? email) → boolean?
  email : mail
procedure
(mail-sender email) → string?
  email : mail?
procedure
(mail-recipients email) → list?
  email : mail?
procedure
(mail-cc-recipients email) → list?
  email : mail?
procedure
(mail-bcc-recipients email) → list?
  email : mail?
procedure
(mail-subject email) → string?
  email : mail?
procedure
(mail-attached-files email) → list?
  email : mail?

mail? check if email is an instance of struct mail or not.
mail-sender returns struct info about who the email was sent from.
mail-recipients returns struct info about who this email was sent to.
mail-cc-recipients returns struct info about who this email was copied to.
mail-bcc-recipients returns struct info about who this email was carbon copied to.
mail-attached-files returns struct info about a list of attachment file paths of this email.

procedure
(mail-header email) → string?
  email : mail?
procedure
(mail-header/info email) → string?
  email : mail?
procedure
(mail-header/body email) → string?
  email : mail?
procedure
(mail-header/attachment email) → string?
  email : mail?

mail-header returns email header which is used for sending.
mail-header/info returns sender, recipients, subject infos of the mail-header of email.