Don't forget to add .env to .gitignore. If you accidentally push the .env file to a public repo, the keys will be detected, alarms will ring and Mailgun/Sendgrid will immediately suspend your account.

# For Amazon SES - also need IAM, Policy and all that guff
AWS_REGION="amazon-ses-region"
AWS_ACCESS_KEY_ID="your-amazon-access-key-id"
AWS_SECRET_ACCESS_KEY="your-amazon-secret-access-key"

# Mailgun is easier
MAILGUN_DOMAIN="your.mailgun.domain"
MAILGUN_API_KEY="your-mailgun-api-key"

# Sengrid, easier again
SENDGRID_API_KEY="your-sendgrid-api-key"

# If Amazon SES account is still in sandbox mode, these email addresses will
# need to be verified before they will work
TEST_SENDER_NAME="8o8 Test Mail"
TEST_SENDER_EMAIL="[email protected]"
TEST_RECIPIENT_NAME="Your Name"
TEST_RECIPIENT_EMAIL="[email protected]"

# Skip test for any value other than "true"
TEST_MAILGUN="true"
TEST_SENDGRID="" # false
TEST_SES=true="" # false

Usage

package main

import "github.com/8o8/email"

func main() {

    em := email.Email{
        FromName: "Send Name",
        FromEmail: "[email protected]",
        ToName: "Recipient Name",
        ToEmail: "[email protected]",
        Subject: "The Subject",
        PlainContent: "This is the plain text",
        HTMLContent: "<h1>This is HTML</h1>",
    }

    // cfg for the specific api
    cfg := email.MailgunCfg{
        APIKey: apiKey,
        Domain: domain,
    }
    mx := email.NewMailgun(cfg)

    err := mx.Send(em)
    if err != nil {
        fmt.Println(err)
    }
}