Method 3) Custom method

This method allows you provide a callback using which you can send emails however you like. The input to the callback will be email template variables, so you can freely design the email as well. Use this method if you are:

Using a third party email service like Mailchimp.
You want to do some custom spam protection before sending the email.
You already have an email sending infrastructure and want to use that.

NodeJS
GoLang
Python

import supertokens from "supertokens-node";
import ThirdParty from "supertokens-node/recipe/thirdparty";
import Session from "supertokens-node/recipe/session";
import EmailVerification from "supertokens-node/recipe/emailverification"

supertokens.init({
    appInfo: {
        apiDomain: "...",
        appName: "...",
        websiteDomain: "..."
    },
    recipeList: [
        ThirdParty.init({
        }),

        EmailVerification.init({
            emailDelivery: {
                override: (originalImplementation) => {
                    return {
                        ...originalImplementation,
                        sendEmail: async function (input) {
                            // TODO: create and send email verification email

                            // Or use the original implementation which calls the default service,
                            // or a service that you may have specified in the emailDelivery object.
                            return originalImplementation.sendEmail(input);
                        }
                    }
                }
            },
        }),
        Session.init()
    ]
});

import (
    "github.com/supertokens/supertokens-golang/ingredients/emaildelivery"
    "github.com/supertokens/supertokens-golang/recipe/emailverification"
    "github.com/supertokens/supertokens-golang/recipe/emailverification/evmodels"
    "github.com/supertokens/supertokens-golang/supertokens"
)

func main() {
    supertokens.Init(supertokens.TypeInput{
        RecipeList: []supertokens.Recipe{
            emailverification.Init(evmodels.TypeInput{
                Mode: evmodels.ModeRequired,
                EmailDelivery: &emaildelivery.TypeInput{
                    Override: func(originalImplementation emaildelivery.EmailDeliveryInterface) emaildelivery.EmailDeliveryInterface {
                        originalSendEmail := *originalImplementation.SendEmail

                        (*originalImplementation.SendEmail) = func(input emaildelivery.EmailType, userContext supertokens.UserContext) error {
                            // TODO: create and email verification email

                            // Or use the original implementation which calls the default service,
                            // or a service that you may have specified in the EmailDelivery object.
                            return originalSendEmail(input, userContext)
                        }

                        return originalImplementation
                    },
                },
            }),
        },
    })
}

from supertokens_python import init, InputAppInfo
from typing import Dict, Any
from supertokens_python.ingredients.emaildelivery.types import EmailDeliveryConfig
from supertokens_python.recipe.emailverification.types import EmailDeliveryOverrideInput as EVEmailDeliveryOverrideInput, EmailTemplateVars as EVEmailTemplateVars
from supertokens_python.recipe import emailverification

def custom_emailverification_delivery(original_implementation: EVEmailDeliveryOverrideInput) -> EVEmailDeliveryOverrideInput:
    original_send_email = original_implementation.send_email

    async def send_email(template_vars: EVEmailTemplateVars, user_context: Dict[str, Any]) -> None:
        # TODO: create and send email verification email

        # Or use the original implementation which calls the default service,
        # or a service that you may have specified in the email_delivery object.
        return await original_send_email(template_vars, user_context)

    original_implementation.send_email = send_email
    return original_implementation


init(
    app_info=InputAppInfo(
        api_domain="...", app_name="...", website_domain="..."),
    framework='...',  
    recipe_list=[
        emailverification.init(
            mode="OPTIONAL",
            email_delivery=EmailDeliveryConfig(override=custom_emailverification_delivery))
    ]
)

If you call the original implementation function for sendEmail, it will use the service that you have configured. If you have not configured any service, it will use the default service.

So using this method, you can for example, have your custom way of sending email verification emails, but use the default or SMTP service to send the reset password emails.

important

When using this callback, you must manage sending the email yourself.