Other: Only listen on localhost and add send test

We should only listen on constants.Host when serving IMAP and SMTP.
This change fixes that. It also adds a test that we can send over SMTP
and receive over IMAP.

internal/bridge/send_test.go

@@ -0,0 +1,98 @@
+// Copyright (c) 2022 Proton AG
+//
+// This file is part of Proton Mail Bridge.
+//
+// Proton Mail Bridge is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Proton Mail Bridge is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Proton Mail Bridge.  If not, see <https://www.gnu.org/licenses/>.
+
+package bridge_test
+
+import (
+	"context"
+	"fmt"
+	"net/smtp"
+	"testing"
+	"time"
+
+	"github.com/ProtonMail/proton-bridge/v2/internal/bridge"
+	"github.com/ProtonMail/proton-bridge/v2/internal/constants"
+	"github.com/emersion/go-imap"
+	"github.com/emersion/go-imap/client"
+	"github.com/stretchr/testify/require"
+	"gitlab.protontech.ch/go/liteapi"
+	"gitlab.protontech.ch/go/liteapi/server"
+)
+
+func TestBridge_Send(t *testing.T) {
+	withEnv(t, func(ctx context.Context, s *server.Server, netCtl *liteapi.NetCtl, locator bridge.Locator, storeKey []byte) {
+		_, _, err := s.CreateUser("recipient", "recipient@pm.me", password)
+		require.NoError(t, err)
+
+		withBridge(ctx, t, s.GetHostURL(), netCtl, locator, storeKey, func(bridge *bridge.Bridge, mocks *bridge.Mocks) {
+			senderUserID, err := bridge.LoginFull(ctx, username, password, nil, nil)
+			require.NoError(t, err)
+
+			recipientUserID, err := bridge.LoginFull(ctx, "recipient", password, nil, nil)
+			require.NoError(t, err)
+
+			senderInfo, err := bridge.GetUserInfo(senderUserID)
+			require.NoError(t, err)
+
+			recipientInfo, err := bridge.GetUserInfo(recipientUserID)
+			require.NoError(t, err)
+
+			for i := 0; i < 10; i++ {
+				// Send an email from sender to recipient.
+				smtpClient, err := smtp.Dial(fmt.Sprintf("%v:%v", constants.Host, bridge.GetSMTPPort()))
+				require.NoError(t, err)
+				defer smtpClient.Close() //nolint:errcheck
+
+				require.NoError(t, smtpClient.Auth(smtp.PlainAuth("", senderInfo.Addresses[0], string(senderInfo.BridgePass), constants.Host)))
+				require.NoError(t, smtpClient.Mail(senderInfo.Addresses[0]))
+				require.NoError(t, smtpClient.Rcpt("recipient@pm.me"))
+
+				wc, err := smtpClient.Data()
+				require.NoError(t, err)
+
+				n, err := fmt.Fprintf(wc, "Subject: Test %v\r\n\r\nHello world!", i)
+				require.NoError(t, err)
+				require.Greater(t, n, 0)
+				require.NoError(t, wc.Close())
+
+				// Sender should see the message in the Sent folder.
+				senderIMAPClient, err := client.Dial(fmt.Sprintf("%v:%v", constants.Host, bridge.GetIMAPPort()))
+				require.NoError(t, err)
+				require.NoError(t, senderIMAPClient.Login(senderInfo.Addresses[0], string(senderInfo.BridgePass)))
+				defer senderIMAPClient.Logout() //nolint:errcheck
+
+				require.Eventually(t, func() bool {
+					status, err := senderIMAPClient.Status(`Sent`, []imap.StatusItem{imap.StatusMessages})
+					require.NoError(t, err)
+					return status.Messages == uint32(i+1)
+				}, 10*time.Second, 100*time.Millisecond)
+
+				// Recipient should see the message in the Inbox.
+				recipientIMAPClient, err := client.Dial(fmt.Sprintf("%v:%v", constants.Host, bridge.GetIMAPPort()))
+				require.NoError(t, err)
+				require.NoError(t, recipientIMAPClient.Login(recipientInfo.Addresses[0], string(recipientInfo.BridgePass)))
+				defer recipientIMAPClient.Logout() //nolint:errcheck
+
+				require.Eventually(t, func() bool {
+					status, err := recipientIMAPClient.Status(`Inbox`, []imap.StatusItem{imap.StatusMessages})
+					require.NoError(t, err)
+					return status.Messages == uint32(i+1)
+				}, 10*time.Second, 100*time.Millisecond)
+			}
+		})
+	})
+}