Enable Mailgun adapter from environment variables

Which (combination of) environment variables are needed to enable the Mailgun adapter within a container deployment?

The primary one would seem to be:

Basing from the following section of a user guide:

It seems the following are needed in the main server config section:

verifyUserEmails: true,
emailVerifyTokenValidityDuration: 2 * 60 * 60,
preventLoginWithUnverifiedEmail: false,
emailAdapter: {
    module: '@parse/simple-mailgun-adapter',
    options: {
      // The address that your emails come from
      fromAddress: '[email protected]',
      // Your domain from mailgun.com
      domain: 'example.com',
      // Your API key from mailgun.com
      apiKey: 'key-mykey',

But I cannot match each of these up to their environment variables, i.e. what is the “fromAddress”, “domain” and “apiKey” values to be used?

I am using the published source code for the environment variables:

I know there are alternative ways to configure Parse server. I am trying this way, from the existing documentation available.

Have you tried to send a JSON string through PARSE_SERVER_EMAIL_ADAPTER env var?