nixos/stalwart-mail: add vm test

  sslh = handleTest ./sslh.nix {};

  sssd = handleTestOn ["x86_64-linux"] ./sssd.nix {};

  sssd-ldap = handleTestOn ["x86_64-linux"] ./sssd-ldap.nix {};

  stalwart-mail = handleTest ./stalwart-mail.nix {};

  stargazer = runTest ./web-servers/stargazer.nix;

  starship = handleTest ./starship.nix {};

  static-web-server = handleTest ./web-servers/static-web-server.nix {};

# Rudimentary test checking that the Stalwart email server can:

# - receive some message through SMTP submission, then

# - serve this message through IMAP.

let

  certs = import ./common/acme/server/snakeoil-certs.nix;

  domain = certs.domain;

in import ./make-test-python.nix ({ lib, ... }: {

  name = "stalwart-mail";

  nodes.main = { pkgs, ... }: {

    security.pki.certificateFiles = [ certs.ca.cert ];

    services.stalwart-mail = {

      enable = true;

      settings = {

        server.hostname = domain;

        certificate."snakeoil" = {

          cert = "file://${certs.${domain}.cert}";

          private-key = "file://${certs.${domain}.key}";

        };

        server.tls = {

          certificate = "snakeoil";

          enable = true;

          implicit = false;

        };

        server.listener = {

          "smtp-submission" = {

            bind = [ "[::]:587" ];

            protocol = "smtp";

          };

          "imap" = {

            bind = [ "[::]:143" ];

            protocol = "imap";

          };

        };

        session.auth.mechanisms = [ "PLAIN" ];

        session.auth.directory = "in-memory";

        jmap.directory = "in-memory";  # shared with imap

        session.rcpt.directory = "in-memory";

        queue.outbound.next-hop = [ "local" ];

        directory."in-memory" = {

          type = "memory";

          users = [

            {

              name = "alice";

              secret = "foobar";

              email = [ "alice@${domain}" ];

            }

            {

              name = "bob";

              secret = "foobar";

              email = [ "bob@${domain}" ];

            }

          ];

        };

      };

    };

    environment.systemPackages = [

      (pkgs.writers.writePython3Bin "test-smtp-submission" { } ''

        from smtplib import SMTP

        with SMTP('localhost', 587) as smtp:

            smtp.starttls()

            smtp.login('alice', 'foobar')

            smtp.sendmail(

                'alice@${domain}',

                'bob@${domain}',

                """

                    From: alice@${domain}

                    To: bob@${domain}

                    Subject: Some test message

                    This is a test message.

                """.strip()

            )

      '')

      (pkgs.writers.writePython3Bin "test-imap-read" { } ''

        from imaplib import IMAP4

        with IMAP4('localhost') as imap:

            imap.starttls()

            imap.login('bob', 'foobar')

            imap.select('"All Mail"')

            status, [ref] = imap.search(None, 'ALL')

            assert status == 'OK'

            [msgId] = ref.split()

            status, msg = imap.fetch(msgId, 'BODY[TEXT]')

            assert status == 'OK'

            assert msg[0][1].strip() == b'This is a test message.'

      '')

    ];

  };

  testScript = /* python */ ''

    main.wait_for_unit("stalwart-mail.service")

    main.wait_for_open_port(587)

    main.wait_for_open_port(143)

    main.succeed("test-smtp-submission")

    main.succeed("test-imap-read")

  '';

  meta = {

    maintainers = with lib.maintainers; [ happysalada pacien ];

  };

})