Sending Emails

Sending emails from Edge Functions using the Resend API.

Prerequisites#

To get the most out of this guide, you’ll need to:

Make sure you have the latest version of the Supabase CLI installed.

1. Create Supabase function#

Create a new function locally:

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supabase functions new resend

Store the RESEND_API_KEY in your .env file.

2. Edit the handler function#

Paste the following code into the index.ts file:

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import { withSupabase } from 'npm:@supabase/server@^1'
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const RESEND_API_KEY = Deno.env.get('RESEND_API_KEY')
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const handler = async (_request: Request): Promise<Response> => {
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  const res = await fetch('https://api.resend.com/emails', {
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    method: 'POST',
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    headers: {
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      'Content-Type': 'application/json',
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      Authorization: `Bearer ${RESEND_API_KEY}`,
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    },
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    body: JSON.stringify({
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      from: 'onboarding@resend.dev',
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      to: 'delivered@resend.dev',
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      subject: 'hello world',
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      html: '<strong>it works!</strong>',
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    }),
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  })
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  const data = await res.json()
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  return Response.json(data)
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}
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export default { fetch: withSupabase({ auth: ['user', 'secret'] }, handler) }

3. Deploy and send email#

Run function locally:

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supabase start
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supabase functions serve --no-verify-jwt --env-file .env

The function accepts a signed-in user's JWT or a secret key, so it can be triggered from your app (via supabase.functions.invoke) or from a database function. Test it locally with a secret key:

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curl -i --request POST 'http://localhost:54321/functions/v1/resend' \
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  --header 'apikey: <SUPABASE_SECRET_KEY>'

Deploy function to Supabase:

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supabase functions deploy resend --no-verify-jwt

When you deploy to Supabase, make sure that your RESEND_API_KEY is set in Edge Function Secrets Management

4. Try it yourself#

Find the complete example on GitHub.