golang邮件抄送
最近接触的一个api模块中使用了smtp.SendMail发送邮件。因为要实现cc功能，看了下源码，简单记录下。
smtp中关于SendMail的声明
SendMail(addr string, a Auth, from string, to []string, msg []byte) error
参数依次是,
addr: smtp server地址，格式为hostname:port 或者 ip:port;
a: smtp PlainAuth信息, 包含identity, username, password, host, 即身份id、用户名、密码、smtp服务器host. identify 一般为空，表明identity与username一致;
from: 发件邮箱
to: 收件人地址列表,包含to，cc，bcc的所有收件地址
msg: 邮件内容,包含邮件header和body
来一个栗子
pacakge main
import (
"fmt"
"smtp"
"strings"
)
func main(){
from := "from@xxx.com"
header := make(map[string]string)
header["From"] = "<I am From>" + from
header["Subject"] = "send mail with golang"
header["Content-Type"] = "text/html; charset=UTF-8"
header["To"] = "a@xxx.com;b@xxx.com"
header["Cc"] = "cc@xxx.com;"
header["Bcc"] = "bcc@xxx.com;"
message:= ""
content = "<html><body>hello, world!</body></html>"
auth := smtp.PlainAuth("", "from@gmail.com","password", "xxx.com")
for k, v := range header {
message += fmt.Sprintf("%s: %s\r\n", k, v)
}
message += "\r\n" + content
to := []string{}
tos := strings.Split(header[To],";")
ccs := strings.Split(header[Cc],";")
bccs := strings.Split(header[Bcc],";")
if len(tos) != 0 {
to = append(to, tos)
}
if len(ccs) != 0 {
to = append(to, ccs)
}
if len(bccs) != 0 {
to = append(to, bccs)
}
err:= smtp.SendMail("xxx.com:25", auth, from, to, []byte(message))
if err !=mil {
fmt.Println(err)
}
fmt.Println("mail sent success")
}
}
Header 中内容只用于在邮件中显示，from 和 Header[«From»]是有区别的，Sendmail中使用的是from. header中的To，Cc，Bcc也是类似，真正to才是收件人。想想邮件组和bcc的实现，还是挺有意思的。