Golang email library

Golang Email Library for sending and receiving emails in Go over SMTP or HTTP/S.

golang email testing

Generate test email accounts and real inboxes in Golang using MailSlurp SDKs. Free for personal use, send and receive emails and attachments in Go code and tests. MailSlurp's free email API enables teams and developers to create email mailboxes on demand then control email accounts in code and applications.

Get started

MailSlurp has an official Golang package and support for Go SMTP clients.

Installing

Install the MailSlurp golang package from github using go get and go mod.

go get github.com/mailslurp/mailslurp-client-go

You may also need these dependencies:

go get golang.org/x/oauth2
go get golang.org/x/net/context
go get github.com/antihax/optional

To configure the MailSlurp client obtain a free API Key. Then import the libraries:

import (
"context"
"github.com/mailslurp/mailslurp-client-go"
)
Then configure the client:


var apiKey = "your-mailslurp-client"

// create a context with your api key
ctx := context.WithValue(
context.Background(),
mailslurp.ContextAPIKey,
mailslurp.APIKey{ Key: apiKey }
)

// create mailslurp client
config := mailslurp.NewConfiguration()
client := mailslurp.NewAPIClient(config)

Example

Here is a short example using stretchr/testify and go test to create email addresses, send emails and receive them.

package main

import (
	"context"
	"github.com/antihax/optional"
	mailslurp "github.com/mailslurp/mailslurp-client-go"
	"github.com/stretchr/testify/assert"
	"os"
	"regexp"
	"testing"
)

var apiKey = os.Getenv("API_KEY")

func getMailSlurpClient(t *testing.T) (*mailslurp.APIClient, context.Context) {
	assert.NotNil(t, apiKey)

	// create a context with your api key
	ctx := context.WithValue(context.Background(), mailslurp.ContextAPIKey, mailslurp.APIKey{ Key: apiKey })

	// create mailslurp client
	config := mailslurp.NewConfiguration()
	client := mailslurp.NewAPIClient(config)

	return client, ctx
}

func Test_CanCreateInbox(t *testing.T) {
	// create a context with your api key
	client, ctx := getMailSlurpClient(t)

	// create an inbox using the inbox controller
	opts := &mailslurp.CreateInboxOpts{}
	inbox, response, err := client.InboxControllerApi.CreateInbox(ctx, opts)

	assert.NoError(t, err)
	assert.Equal(t, response.StatusCode, 201)
	assert.Contains(t, inbox.EmailAddress, "@mailslurp.com")
}

func Test_CanSendEmail(t *testing.T) {
	// create a context with your api key
	client, ctx := getMailSlurpClient(t)

	// create an inbox we can send email from
	inbox, _, _ := client.InboxControllerApi.CreateInbox(ctx, nil)

	// send email from inbox
	sendEmailOptions := mailslurp.SendEmailOptions{
		To: []string{inbox.EmailAddress},
		Subject: "Test email",
		Body: "<h1>MailSlurp supports HTML</h1>",
		IsHTML: true,
	}
	opts := &mailslurp.SendEmailOpts{
		SendEmailOptions: optional.NewInterface(sendEmailOptions),
	}
	res, err := client.InboxControllerApi.SendEmail(ctx, inbox.Id, opts)

	assert.NoError(t,err)
	assert.Equal(t, res.StatusCode, 201)
}


func Test_CanReceiveEmail(t *testing.T) {
	// create a context with your api key
	client, ctx := getMailSlurpClient(t)

	// create two inboxes for testing
	inbox1, _, _ := client.InboxControllerApi.CreateInbox(ctx, nil)
	inbox2, _, _ := client.InboxControllerApi.CreateInbox(ctx, nil)

	// send email from inbox1 to inbox2
	sendEmailOptions := mailslurp.SendEmailOptions{
		To: []string{inbox2.EmailAddress},
		Subject: "Hello inbox2",
		Body: "Your code is: 123",
	}
	sendOpts := &mailslurp.SendEmailOpts{
		SendEmailOptions: optional.NewInterface(sendEmailOptions),
	}
	res, err := client.InboxControllerApi.SendEmail(ctx, inbox1.Id, sendOpts)

	assert.NoError(t,err)
	assert.Equal(t, res.StatusCode, 201)

	// fetch the email for inbox2
	waitOpts := &mailslurp.WaitForLatestEmailOpts{
		InboxId: optional.NewInterface(inbox2.Id),
		Timeout: optional.NewInt64(30000),
		UnreadOnly: optional.NewBool(true),
	}
	email, _, err := client.WaitForControllerApi.WaitForLatestEmail(ctx, waitOpts)
	assert.NoError(t,err)
	assert.Contains(t, email.Subject, "Hello inbox2")
	assert.Contains(t, email.Body, "Your code is")

	// can extract the contents
	r := regexp.MustCompile(`Your code is: ([0-9]{3})`)
	code := r.FindStringSubmatch(email.Body)[1]
	assert.Equal(t, code, "123")
}

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