We build too many walls and not enough bridges

test/mocks/smtp.go

@@ -0,0 +1,182 @@
+// Copyright (c) 2020 Proton Technologies AG
+//
+// This file is part of ProtonMail Bridge.Bridge.
+//
+// ProtonMail 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.
+//
+// ProtonMail 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 ProtonMail Bridge.  If not, see <https://www.gnu.org/licenses/>.
+
+package mocks
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+	"io"
+	"net"
+	"net/mail"
+	"os"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/pkg/errors"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+type SMTPClient struct {
+	lock     *sync.Mutex
+	debug    *debug
+	t        TestingT
+	conn     net.Conn
+	response *bufio.Reader
+	address  string
+}
+
+func NewSMTPClient(t TestingT, tag, smtpAddr string) *SMTPClient {
+	conn, err := net.Dial("tcp", smtpAddr)
+	require.NoError(t, err)
+	response := bufio.NewReader(conn)
+
+	// Read first response to opening connection.
+	_, err = response.ReadString('\n')
+	assert.NoError(t, err)
+
+	return &SMTPClient{
+		lock:     &sync.Mutex{},
+		debug:    newDebug(tag),
+		t:        t,
+		conn:     conn,
+		response: response,
+	}
+}
+
+func (c *SMTPClient) Close() {
+	c.lock.Lock()
+	defer c.lock.Unlock()
+	_ = c.conn.Close()
+}
+
+func (c *SMTPClient) SendCommands(commands ...string) *SMTPResponse {
+	c.lock.Lock()
+	defer c.lock.Unlock()
+
+	smtpResponse := &SMTPResponse{t: c.t}
+
+	for _, command := range commands {
+		tstart := time.Now()
+
+		c.debug.printReq(command)
+		fmt.Fprintf(c.conn, "%s\r\n", command)
+
+		message, err := c.response.ReadString('\n')
+		if err != nil {
+			smtpResponse.err = fmt.Errorf("read response failed: %v", err)
+			return smtpResponse
+		}
+
+		// Message contains code and message. Codes 4xx and 5xx are bad ones, except "500 Speak up".
+		if strings.HasPrefix(message, "4") || strings.HasPrefix(message, "5") {
+			c.debug.printErr(message)
+			err := errors.New(strings.Trim(message, "\r\n"))
+			smtpResponse.err = errors.Wrap(err, "SMTP error")
+			return smtpResponse
+		} else if command != "" && len(message) == 0 {
+			err := errors.New("empty answer")
+			smtpResponse.err = errors.Wrap(err, "SMTP error")
+			return smtpResponse
+		}
+
+		c.debug.printRes(message)
+		smtpResponse.result = message
+
+		c.debug.printTime(time.Since(tstart))
+	}
+
+	return smtpResponse
+}
+
+// Auth
+
+func (c *SMTPClient) Login(account, password string) *SMTPResponse {
+	c.address = account
+	return c.SendCommands(
+		"HELO ATEIST.TEST",
+		"AUTH LOGIN",
+		base64(account),
+		base64(password),
+	)
+}
+
+func (c *SMTPClient) Logout() *SMTPResponse {
+	return c.SendCommands("QUIT")
+}
+
+// Sending
+
+func (c *SMTPClient) EML(fileName, bcc string) *SMTPResponse {
+	f, err := os.Open(fileName) //nolint[gosec]
+	if err != nil {
+		panic(fmt.Errorf("smtp eml open: %s", err))
+	}
+	defer f.Close() //nolint[errcheck]
+
+	return c.SendMail(f, bcc)
+}
+
+func (c *SMTPClient) SendMail(r io.Reader, bcc string) *SMTPResponse {
+	var message, from string
+	var tos []string
+	if bcc != "" {
+		tos = append(tos, bcc)
+	}
+
+	scanner := bufio.NewScanner(r)
+	for scanner.Scan() {
+		line := string(bytes.Trim(scanner.Bytes(), "\r\n")) // Make sure no line ending is there.
+		message += line + "\r\n"
+
+		from = c.address
+		if from == "" && strings.HasPrefix(line, "From: ") {
+			if addr, err := mail.ParseAddress(line[6:]); err == nil {
+				from = addr.Address
+			}
+		}
+		if strings.HasPrefix(line, "To: ") || strings.HasPrefix(line, "CC: ") {
+			if addrs, err := mail.ParseAddressList(line[4:]); err == nil {
+				for _, addr := range addrs {
+					tos = append(tos, addr.Address)
+				}
+			}
+		}
+	}
+
+	if err := scanner.Err(); err != nil {
+		panic(fmt.Errorf("smtp eml scan: %s", err))
+	}
+	if from == "" {
+		panic(fmt.Errorf("smtp eml no from"))
+	}
+	if len(tos) == 0 {
+		panic(fmt.Errorf("smtp eml no to"))
+	}
+
+	commands := []string{
+		fmt.Sprintf("MAIL FROM:<%s>", from),
+	}
+	for _, to := range tos {
+		commands = append(commands, fmt.Sprintf("RCPT TO:<%s>", to))
+	}
+	commands = append(commands, "DATA", message+"\r\n.") // Message ending.
+	return c.SendCommands(commands...)
+}