Supabase Edge Function Can't Send Email

Question

I'm trying to send and email using SmtpClient from deno, and configuring it using gmail app password. strange thing is when i serve the function locally emails get sent but once deployed i get the following error in the function logs

TypeError: Deno.writeAll is not a function
    at BufWriter.flush (https://deno.land/[email protected]/io/bufio.ts:394:24)
    at SmtpClient.writeCmd (https://deno.land/x/[email protected]/smtp.ts:125:28)
    at eventLoopTick (ext:core/01_core.js:183:11)
    at async SmtpClient._connect (https://deno.land/x/[email protected]/smtp.ts:82:9)
    at async SmtpClient.connectTLS (https://deno.land/x/[email protected]/smtp.ts:39:9)
    at async Server.<anonymous> (file:///src/index.ts:847:9)
    at async Server.#respond (https://deno.land/[email protected]/http/server.ts:221:24)

i tried wrapping every dangerous operations in try catch block no errors return except the on i find in logs

Answer 1

I had the same problem and found a solution here: https://deno.land/x/[email protected]

This is how to implement it

// supabase/functions/sendMail/index.ts

import { SMTPClient } from "https://deno.land/x/denomailer/mod.ts";

const smtp = new SMTPClient({
    connection: {
      hostname: "smtp.gmail.com",
      port: 465,
      tls: true,
      auth: {
        username: Deno.env.GMAIL_USER,
        password: Deno.env.GMAIL_PASSWORD,
      },
    },
  })

Deno.serve(async (req) => {
  try {
    await smtp.send({
      from: Deno.env.GMAIL_USER,
      to: req.to,
      subject: `Your Subject Line`,
      content: `Content that could be plain text or HTML`,
    })
  } catch (error) {
    return new Response(error.message, { status: 500 })
  }

  await smtp.close()

  return new Response(
    JSON.stringify({
      done: true,
    }),
    {
      headers: { 'Content-Type': 'application/json' },
    }
  )
})