test(mailer): improve

go.mod

@@ -20,6 +20,7 @@ require (
 	github.com/stretchr/testify v1.7.0
 	golang.org/x/crypto v0.0.0-20210513164829-c07d793c2f9a
 	golang.org/x/time v0.0.0-20210220033141-f8bda1e9f3ba
+	golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 // indirect
 	gopkg.in/alexcesaro/quotedprintable.v3 v3.0.0-20150716171945-2caba252f4dc // indirect
 	gopkg.in/mail.v2 v2.3.1 // indirect
 	gorm.io/driver/postgres v1.1.0

go.sum

@@ -578,8 +578,9 @@ golang.org/x/xerrors v0.0.0-20190410155217-1f06c39b4373/go.mod h1:I/5z698sn9Ka8T
 golang.org/x/xerrors v0.0.0-20190513163551-3ee3066db522/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
-golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543 h1:E7g+9GITq07hpfrRu66IVDexMakfv52eLZ2CXBWiKr4=
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
+golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 h1:go1bK/D/BFZV2I8cIQd1NKEZ+0owSTG1fDTci4IqFcE=
+golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 google.golang.org/api v0.3.1/go.mod h1:6wY9I6uQWHQ8EM57III9mq/AjF+i8G65rmVagqKMtkk=
 google.golang.org/appengine v1.1.0/go.mod h1:EbEs0AVv82hx2wNQdGPgUI5lhzA/G0D9YwlJXL52JkM=
 google.golang.org/appengine v1.2.0/go.mod h1:xpcJRLb0r/rnEns0DIKYYv+WjYCduHsrkT7/EB5XEv4=

mailer/main_test.go

@@ -1 +1,25 @@
 package mailer
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestSetupAndPing(t *testing.T) {
+	assert := assert.New(t)
+
+	mock, s := NewFakeServer()
+	assert.NotNil(mock)
+	// correct setup
+	err := s.Setup()
+	assert.NoError(err)
+	mock.Close()
+
+	s.SMTPPassword = "wrong"
+	mock, s = newFakeServer(s)
+	// wrong password
+	err = s.Setup()
+	assert.Error(err)
+	mock.Close()
+}

mailer/test.go

@@ -0,0 +1,89 @@
+package mailer
+
+import (
+	"errors"
+	"fmt"
+	"net"
+	"net/textproto"
+
+	"github.com/bdlm/log"
+)
+
+type fakeServer struct {
+	s *Service
+	l net.Listener
+}
+
+// NewFakeServer - to get mocked Service for mail-service
+func NewFakeServer() (*fakeServer, *Service) {
+	s := &Service{
+		SMTPHost:     "127.0.0.1",
+		SMTPPort:     12025,
+		SMTPUsername: "user",
+		SMTPPassword: "password",
+		SMTPSSL:      false,
+	}
+	return newFakeServer(s)
+}
+
+func newFakeServer(s *Service) (*fakeServer, *Service) {
+	fs := &fakeServer{
+		s: s,
+	}
+	l, err := net.Listen("tcp", fmt.Sprintf("%s:%d", fs.s.SMTPHost, fs.s.SMTPPort))
+	if err != nil {
+		log.Panicf("Error listing: %s", err)
+		return nil, nil
+	}
+	fs.l = l
+	go fs.run()
+	return fs, s
+}
+
+func (fs *fakeServer) Close() {
+	fs.l.Close()
+}
+
+func (fs *fakeServer) run() {
+	for {
+		conn, err := fs.l.Accept()
+		if err != nil {
+			if errors.Is(err, net.ErrClosed) {
+				return
+			}
+			log.Panicf("Error accepting: %s", err)
+		}
+		go fs.handle(conn)
+	}
+}
+func (fs *fakeServer) handle(conn net.Conn) {
+	defer conn.Close()
+	c := textproto.NewConn(conn)
+	defer c.Close()
+
+	c.Cmd("220 localhost.fake ESMTP Postfix")
+	s, _ := c.ReadLine()
+	if len(s) < 6 || s[:4] != "EHLO" {
+		c.Cmd("221 Bye")
+		return
+	}
+	c.Cmd("250-Hello %s", s[5:])
+	c.Cmd("250-PIPELINIG")
+	c.Cmd("250 AUTH PLAIN")
+	s, _ = c.ReadLine()
+	if s == "AUTH PLAIN AHVzZXIAcGFzc3dvcmQ=" {
+		c.Cmd("235 Authentication successful")
+	} else {
+		c.Cmd("535 Authentication failed")
+		c.Cmd("221 Bye")
+		return
+	}
+	for {
+		s, _ = c.ReadLine()
+		switch s {
+		case "QUIT":
+			c.Cmd("221 Bye")
+			return
+		}
+	}
+}

mailer/test_test.go

@@ -0,0 +1,25 @@
+package mailer
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestFakeServer(t *testing.T) {
+	assert := assert.New(t)
+
+	s := &Service{
+		SMTPHost:     "127.0.0.1",
+		SMTPPort:     -2,
+		SMTPUsername: "user",
+		SMTPPassword: "password",
+		SMTPSSL:      false,
+	}
+
+	// Port
+	assert.Panics(func() {
+		mock, _ := newFakeServer(s)
+		mock.Close()
+	})
+}

web/main_test.go

@@ -13,7 +13,7 @@ func TestRun(t *testing.T) {
 	ModuleRegister(func(_ *gin.Engine, _ *Service) {
 	})
 
-	s := &Service{AccessLog: true, Listen: ":80"}
+	s := &Service{AccessLog: true, Listen: "8.8.8.8:80"}
 	// HTTP - failed
 	err := s.Run()
 	assert.Error(err)