The library is a wrapper around the stdlib net/smtp
simplifying email sending. It supports authentication, SSL/TLS,
user-specified SMTP servers, content-type, charset, multiple recipients and more.
Usage example:
client := email.NewSender("localhost", email.ContentType("text/html"), email.Auth("user", "pass"))
err := client.Send("<html>some content, foo bar</html>",
email.Params{From: "me@example.com", To: []string{"to@example.com"}, Subject: "Hello world!",
Attachments: []string{"/path/to/file1.txt", "/path/to/file2.txt"},
InlineImages: []string{"/path/to/image1.png", "/path/to/image2.png"},
})
NewSender
accepts a number of options to configure the client:
Port
: SMTP port (default: 25)TLS
: Use TLS SMTP (default: false)STARTTLS
: Use STARTTLS (default: false)InsecureSkipVerify
: skip certificate verification (default: false)Auth(user, password)
: Username and password for SMTP authentication (default: empty, no authentication)LoginAuth
: Use LOGIN mechanism instead of PLAIN mechanism for SMTP authentication, e.g. this is relevant for Office 365 and Outlook.comContentType
: Content type for the email (default: "text/plain")Charset
: Charset for the email (default: "utf-8")TimeOut
: Timeout for the SMTP connection (default: 30 seconds)Log
: Logger to use (default: no logging)SMTP
: Set custom smtp client (default: none)See go docs for Option
functions.
Options should be passed to NewSender
after the mandatory first (host) parameter.
To send email user need to create a sender first and then use Send
method. The method accepts two parameters:
email.Params
)
type Params struct {
From string // From email field
To []string // From email field
Subject string // Email subject
UnsubscribeLink string // POST, https://support.google.com/mail/answer/81126 -> "Use one-click unsubscribe"
InReplyTo string // Identifier for email group (category), used for email grouping
Attachments []string // Attachments path
InlineImages []string // Embedding directly to email body. Autogenerated Content-Id (cid) equals to file name
}
See go docs for Send
function.
quoted-printable
smtp.Client
from stdlib) can be set by user with SMTP
option. In this case it will be used instead of making a new smtp client internally.Log
option. It should implement email.Logger
interface with a single Logf(format string, args ...interface{})
method. By default, "no logging" internal logger is used. This interface is compatible with the go-pkgz/lgr
logger.net/smtp
package.TLS
option (usually on port 465) as well as with STARTTLS
(usually on port 587).This library is not intended to be used for sending a lot of massive emails with low latency requirements. The intended use case is sending simple messages, like alerts, notification and so on. For example, sending alerts from a monitoring system, or for authentication-related emails, i.e. "password reset email", "verification email", etc.