Integrations

Send email from Go with the standard library.

Go needs no Notix package: the API is one HTTPS POST, and net/http with encoding/json covers it. Give every request a context with a deadline and an idempotency key, and the send is safe to retry from a worker or a handler.

The send

Send an email from Go.

send.go

body, _ := json.Marshal(map[string]any{
	"from":    "Acme <receipts@acme.com>",
	"to":      "maria@example.com",
	"subject": "Your receipt",
	"html":    "<p>Thanks for your order.</p>",
})

ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
defer cancel()

req, _ := http.NewRequestWithContext(ctx, http.MethodPost, "https://app.usenotix.dev/api/v1/emails", bytes.NewReader(body))
req.Header.Set("Authorization", "Bearer "+os.Getenv("NOTIX_API_KEY"))
req.Header.Set("Content-Type", "application/json")
req.Header.Set("Idempotency-Key", "order-4471-receipt")

resp, err := http.DefaultClient.Do(req)

The from address must be on a domain you have verified in Notix. Step by step: the cURL quickstart and the longer guide to sending email from Go.

Environment

One API key, kept on the server.

Create an API key on the API keys page of the Notix console and store it as NOTIX_API_KEY in the process environment. Read it only in code that runs on the server, never in anything shipped to a browser.

A Send only key is enough for code that only sends: if it leaks, it cannot read your contacts or delete a domain.

.env

NOTIX_API_KEY=notix_xxxxxxxxxxxx
NOTIX_WEBHOOK_SECRET=whsec_xxxxxxxxxxxx

SMTP relay

Or point net/smtp at the relay.

The relay is smtp.usenotix.dev on port 465 (implicit TLS) or 587 (STARTTLS). The username is always notix and the password is your API key, so net/smtp sends through Notix without new code. Mail sent this way gets the same suppression list, tracking and webhooks as the API.

Port 587 with STARTTLS

auth := smtp.PlainAuth("", "notix", os.Getenv("NOTIX_API_KEY"), "smtp.usenotix.dev")
err := smtp.SendMail("smtp.usenotix.dev:587", auth, "receipts@acme.com", []string{"maria@example.com"}, message)

FAQ

Questions, answered.

Is there a Notix SDK for Go?

No. Notix publishes SDKs for TypeScript, Python and PHP. From Go the integration is the JSON API over HTTPS, or the SMTP relay, and both send through the same pipeline.

What if the same request runs twice?

Send an Idempotency-Key header (idempotencyKey in notix-js) with a value that names the thing being sent, such as order-4471-receipt. A repeat with the same key and body returns the first result and sends nothing new; the same key with a different body is refused with 409.

Why is my send refused with a from-address error?

The from address must be on a domain you have verified in Notix. Add the domain in the console, publish the DNS records it shows, and wait for verification; until then, sends from that domain are refused.

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