feat: add smtp and urn

Author: katallaxie

Diff for: go.mod

@@ -8,9 +8,11 @@ require (
 	firebase.google.com/go/v4 v4.15.2
 	github.com/creack/pty v1.1.24
 	github.com/fatih/color v1.18.0
+	github.com/go-playground/validator/v10 v10.19.0
 	github.com/gofiber/fiber/v2 v2.52.6
 	github.com/google/uuid v1.6.0
 	github.com/jackc/pgx/v5 v5.7.2
+	github.com/katallaxie/pkg v0.6.6
 	github.com/openfga/go-sdk v0.6.5
 	github.com/spf13/cobra v1.9.1
 	github.com/spf13/pflag v1.0.6
@@ -41,12 +43,15 @@ require (
 	github.com/evanphx/json-patch/v5 v5.9.11 // indirect
 	github.com/felixge/httpsnoop v1.0.4 // indirect
 	github.com/fxamacker/cbor/v2 v2.7.0 // indirect
+	github.com/gabriel-vasile/mimetype v1.4.3 // indirect
 	github.com/ghodss/yaml v1.0.0 // indirect
 	github.com/go-logr/logr v1.4.2 // indirect
 	github.com/go-logr/stdr v1.2.2 // indirect
 	github.com/go-openapi/jsonpointer v0.21.0 // indirect
 	github.com/go-openapi/jsonreference v0.20.2 // indirect
 	github.com/go-openapi/swag v0.23.0 // indirect
+	github.com/go-playground/locales v0.14.1 // indirect
+	github.com/go-playground/universal-translator v0.18.1 // indirect
 	github.com/gobwas/glob v0.2.3 // indirect
 	github.com/gogo/protobuf v1.3.2 // indirect
 	github.com/golang/protobuf v1.5.4 // indirect
@@ -67,6 +72,7 @@ require (
 	github.com/klauspost/compress v1.17.9 // indirect
 	github.com/kr/pretty v0.3.1 // indirect
 	github.com/kr/text v0.2.0 // indirect
+	github.com/leodido/go-urn v1.4.0 // indirect
 	github.com/mailru/easyjson v0.7.7 // indirect
 	github.com/mattn/go-colorable v0.1.13 // indirect
 	github.com/mattn/go-isatty v0.0.20 // indirect

Diff for: go.sum

@@ -32,6 +32,8 @@ github.com/felixge/httpsnoop v1.0.4 h1:NFTV2Zj1bL4mc9sqWACXbQFVBBg2W3GPvqp8/ESS2
 github.com/felixge/httpsnoop v1.0.4/go.mod h1:m8KPJKqk1gH5J9DgRY2ASl2lWCfGKXixSwevea8zH2U=
 github.com/fxamacker/cbor/v2 v2.7.0 h1:iM5WgngdRBanHcxugY4JySA0nk1wZorNOpTgCMedv5E=
 github.com/fxamacker/cbor/v2 v2.7.0/go.mod h1:pxXPTn3joSm21Gbwsv0w9OSA2y1HFR9qXEeXQVeNoDQ=
+github.com/gabriel-vasile/mimetype v1.4.3 h1:in2uUcidCuFcDKtdcBxlR0rJ1+fsokWf+uqxgUFjbI0=
+github.com/gabriel-vasile/mimetype v1.4.3/go.mod h1:d8uq/6HKRL6CGdk+aubisF/M5GcPfT7nKyLpA0lbSSk=
 github.com/ghodss/yaml v1.0.0 h1:wQHKEahhL6wmXdzwWG11gIVCkOv05bNOh+Rxn0yngAk=
 github.com/ghodss/yaml v1.0.0/go.mod h1:4dBDuWmgqj2HViK6kFavaiC9ZROes6MMH2rRYeMEF04=
 github.com/go-logr/logr v1.2.2/go.mod h1:jdQByPbusPIv2/zmleS9BjJVeZ6kBagPoEUsqbVz/1A=
@@ -49,6 +51,14 @@ github.com/go-openapi/jsonreference v0.20.2/go.mod h1:Bl1zwGIM8/wsvqjsOQLJ/SH+En
 github.com/go-openapi/swag v0.22.3/go.mod h1:UzaqsxGiab7freDnrUUra0MwWfN/q7tE4j+VcZ0yl14=
 github.com/go-openapi/swag v0.23.0 h1:vsEVJDUo2hPJ2tu0/Xc+4noaxyEffXNIs3cOULZ+GrE=
 github.com/go-openapi/swag v0.23.0/go.mod h1:esZ8ITTYEsH1V2trKHjAN8Ai7xHb8RV+YSZ577vPjgQ=
+github.com/go-playground/assert/v2 v2.2.0 h1:JvknZsQTYeFEAhQwI4qEt9cyV5ONwRHC+lYKSsYSR8s=
+github.com/go-playground/assert/v2 v2.2.0/go.mod h1:VDjEfimB/XKnb+ZQfWdccd7VUvScMdVu0Titje2rxJ4=
+github.com/go-playground/locales v0.14.1 h1:EWaQ/wswjilfKLTECiXz7Rh+3BjFhfDFKv/oXslEjJA=
+github.com/go-playground/locales v0.14.1/go.mod h1:hxrqLVvrK65+Rwrd5Fc6F2O76J/NuW9t0sjnWqG1slY=
+github.com/go-playground/universal-translator v0.18.1 h1:Bcnm0ZwsGyWbCzImXv+pAJnYK9S473LQFuzCbDbfSFY=
+github.com/go-playground/universal-translator v0.18.1/go.mod h1:xekY+UJKNuX9WP91TpwSH2VMlDf28Uj24BCp08ZFTUY=
+github.com/go-playground/validator/v10 v10.19.0 h1:ol+5Fu+cSq9JD7SoSqe04GMI92cbn0+wvQ3bZ8b/AU4=
+github.com/go-playground/validator/v10 v10.19.0/go.mod h1:dbuPbCMFw/DrkbEynArYaCwl3amGuJotoKCe95atGMM=
 github.com/go-task/slim-sprig/v3 v3.0.0 h1:sUs3vkvUymDpBKi3qH1YSqBQk9+9D/8M2mN1vB6EwHI=
 github.com/go-task/slim-sprig/v3 v3.0.0/go.mod h1:W848ghGpv3Qj3dhTPRyJypKRiqCdHZiAzKg9hl15HA8=
 github.com/gobwas/glob v0.2.3 h1:A4xDbljILXROh+kObIiy5kIaPYD8e96x1tgBhUI5J+Y=
@@ -97,6 +107,8 @@ github.com/josharian/intern v1.0.0 h1:vlS4z54oSdjm0bgjRigI+G1HpF+tI+9rE5LLzOg8Hm
 github.com/josharian/intern v1.0.0/go.mod h1:5DoeVV0s6jJacbCEi61lwdGj/aVlrQvzHFFd8Hwg//Y=
 github.com/json-iterator/go v1.1.12 h1:PV8peI4a0ysnczrg+LtxykD8LfKY9ML6u2jnxaEnrnM=
 github.com/json-iterator/go v1.1.12/go.mod h1:e30LSqwooZae/UwlEbR2852Gd8hjQvJoHmT4TnhNGBo=
+github.com/katallaxie/pkg v0.6.6 h1:+qQBCoz5vRYENaL/uwTlks15Px4GDCdhybAZFg8s79c=
+github.com/katallaxie/pkg v0.6.6/go.mod h1:FJNit/KFQGJ5o0XEJN711gfLVxNU1RlXFTboctkVP4A=
 github.com/kisielk/errcheck v1.5.0/go.mod h1:pFxgyoBC7bSaBwPgfKdkLd5X25qrDl4LWUI2bnpBCr8=
 github.com/kisielk/gotool v1.0.0/go.mod h1:XhKaO+MFFWcvkIS/tQcRk01m1F5IRFswLeQ+oQHNcck=
 github.com/klauspost/compress v1.17.9 h1:6KIumPrER1LHsvBVuDa0r5xaG0Es51mhhB9BQB2qeMA=
@@ -108,6 +120,8 @@ github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
 github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
 github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
 github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
+github.com/leodido/go-urn v1.4.0 h1:WT9HwE9SGECu3lg4d/dIA+jxlljEa1/ffXKmRjqdmIQ=
+github.com/leodido/go-urn v1.4.0/go.mod h1:bvxc+MVxLKB4z00jd1z+Dvzr47oO32F/QSNjSBOlFxI=
 github.com/mailru/easyjson v0.7.7 h1:UGYAvKxe3sBsEDzO8ZeWOSlIQfWFlxbzLZe7hwFURr0=
 github.com/mailru/easyjson v0.7.7/go.mod h1:xzfreul335JAWq5oZzymOObrkdz5UnU4kGfJJLY9Nlc=
 github.com/mattn/go-colorable v0.1.13 h1:fFA4WZxdEF4tXPZVKMLwD8oUnCTTo08duU7wxecdEvA=

Diff for: smtp/doc.go

@@ -0,0 +1,2 @@
+// Package smtp provides SMTP primitives.
+package smtp

Diff for: smtp/email.go

@@ -0,0 +1,56 @@
+package smtp
+
+import (
+	"github.com/katallaxie/pkg/ulid"
+)
+
+// Header ...
+type Header string
+
+// Subject ...
+const Subject Header = "Subject"
+
+// From ...
+const From Header = "From"
+
+// To ...
+const To Header = "To"
+
+// Cc ...
+const Cc Header = "Cc"
+
+// Bcc ...
+const Bcc Header = "Bcc"
+
+// ReplyTo ...
+const ReplyTo Header = "Reply-To"
+
+// Date ...
+const Date Header = "Date"
+
+// Message ...
+type Message struct {
+	// ID ...
+	ID string `json:"id" yaml:"id"`
+	// Headers ...
+	Headers map[Header][]string `json:"headers" yaml:"headers"`
+}
+
+// SetID ...
+func (m *Message) SetID(id string) {
+	m.ID = id
+}
+
+// NewMessage ...
+func NewMessage() (*Message, error) {
+	id, err := ulid.NewReverse()
+	if err != nil {
+		return nil, err
+	}
+
+	m := new(Message)
+	m.SetID(id.String())
+	m.Headers = map[Header][]string{}
+
+	return m, nil
+}

Diff for: smtp/email_test.go

@@ -0,0 +1,18 @@
+package smtp
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestNewMesage(t *testing.T) {
+	t.Parallel()
+
+	m, err := NewMessage()
+	require.NoError(t, err)
+	assert.NotNil(t, m)
+	assert.NotEmpty(t, m.ID)
+	assert.Equal(t, map[Header][]string{}, m.Headers)
+}

Diff for: smtp/parser.go

@@ -0,0 +1,29 @@
+package smtp
+
+// Verb is a command verb of SMTP.
+type Verb string
+
+const (
+	// HELO is the SMTP verb for HELO.
+	HELO Verb = "HELO"
+	// EHLO is the SMTP verb for EHLO.
+	EHLO Verb = "EHLO"
+	// MAIL is the SMTP verb for MAIL.
+	MAIL Verb = "MAIL"
+	// RCPT is the SMTP verb for RCPT.
+	RCPT Verb = "RCPT"
+	// DATA is the SMTP verb for DATA.
+	DATA Verb = "DATA"
+	// QUI is the SMTP verb for QUIT.
+	QUIT Verb = "QUIT"
+	// RSET is the SMTP verb for RSET.
+	RSET Verb = "RSET"
+	// NOOP is the SMTP verb for NOOP.
+	NOOP Verb = "NOOP"
+	// HELP is the SMTP verb for HELP.
+	HELP Verb = "HELP"
+	// STARTTLS is the SMTP verb for STARTTLS.
+	STARTTLS Verb = "STARTTLS"
+	// AUTH is the SMTP verb for AUTH.
+	AUTH Verb = "AUTH"
+)

Diff for: smtp/rfc3463.go

@@ -0,0 +1,39 @@
+package smtp
+
+import "fmt"
+
+// EnhancedStatusCodeUnknown is the default value for the enhanced status code.
+var EnhancedStatusCodeUnknown EnhancedMailSystemStatusCode = EnhancedMailSystemStatusCode{-1, -1, -1}
+
+// EnhancedStatusCode is a data structure to contain enhanced
+// mail system status codes from RFC 3463 (https://datatracker.ietf.org/doc/html/rfc3463).
+type EnhancedStatusCode [3]int
+
+// Class returns the class of the enhanced status code.
+func (e EnhancedStatusCode) Class() int {
+	return e[0]
+}
+
+// Subject returns the subject of the enhanced status code.
+func (e EnhancedStatusCode) Subject() int {
+	return e[1]
+}
+
+// Detail returns the detail of the enhanced status code.
+func (e EnhancedStatusCode) Detail() int {
+	return e[2]
+}
+
+// String returns the string representation of the enhanced status code.
+func (e EnhancedMailSystemStatusCode) String() string {
+	return fmt.Sprintf("%v.%v.%v", e[0], e[1], e[2])
+}
+
+const (
+	// Signals a positive delivery action.
+	EnhancedStatusCodeClassSuccess int = 2
+	// Signals that there is a temporary failure in positively delivery action.
+	EnhancedStatusCodeClassPersistentTransientFailure int = 4
+	// Signals that there is a permanent failure in the delivery action.
+	EnhancedStatusCodeClassPermanentFailure int = 5
+)

Diff for: smtp/rfc5321.go

@@ -0,0 +1,39 @@
+package smtp
+
+// ReplyCode is the status code for the SMTP server.
+type ReplyCode int
+
+const (
+	// ReplyCodeSystemStatus is the status code for the system status.
+	ReplyCodeSystemStatus = 211
+	// ReplyCodeHelpMessage is the status code for the help message.
+	ReplyCodeHelpMessage = 214
+	// ReplyCodeServiceReady is the status code for the service ready.
+	ReplyCodeServiceReady = 220
+	// ReplyCodeServiceClosing is the status code for the service closing.
+	ReplyCodeServiceClosing = 221
+	// ReplyCodeAuthenticationSuccessful is the status code for the authentication successful.
+	ReplyCodeMailActionOkay = 250
+	// ReplyCodeUserNotLocal is the status code for the user not local.
+	ReplyCodeMailActionCompleted = 250
+	// ReplyCodeCannotVerifyUser is the status code for the cannot verify user.
+	ReplyCodeUserNotLocal = 251
+	// ReplyCodeStartMailInput is the status code for the start mail input.
+	ReplyCodeCannotVerifyUser               = 252
+	ReplyCodeStartMailInput                 = 354
+	ReplyCodeServiceNotAvailable            = 421
+	ReplyCodeMailboxUnavailable             = 450
+	ReplyCodeLocalError                     = 451
+	ReplyCodeInsufficientStorage            = 452
+	ReplyCodeSyntaxError                    = 500
+	ReplyCodeSyntaxErrorInParameters        = 501
+	ReplyCodeCommandNotImplemented          = 502
+	ReplyCodeCommandBadSequence             = 503
+	ReplyCodeCommandParameterNotImplemented = 504
+	ReplyCodeRequestActionNotTaken          = 550
+	ReplyCodeUserNotLocalForThisHost        = 551
+	ReplyCodeRequestedActionAborted         = 552
+	ReplyCodeRequestedActionNotTaken        = 553
+	ReplyCodeTransactionFailed              = 554
+	ReplyCodeMailFromOrRcptToError          = 555
+)

Diff for: smtp/server.go

@@ -0,0 +1,72 @@
+package smtp
+
+import (
+	"context"
+	"net"
+	"sync"
+
+	"github.com/katallaxie/pkg/group"
+	"github.com/katallaxie/pkg/server"
+)
+
+type mta struct {
+	opts *Opts
+
+	sync.Mutex
+}
+
+// MTA ...
+type MTA interface {
+	server.Listener
+}
+
+const (
+	Network = "tcp"
+)
+
+// Opt ...
+type Opt func(*Opts)
+
+// Opts ...
+type Opts struct {
+	Addr string
+}
+
+// Configure ...
+func (o *Opts) Configure(opts ...Opt) {
+	for _, opt := range opts {
+		opt(o)
+	}
+}
+
+// New ...
+func New(opts ...Opt) *mta {
+	options := new(Opts)
+	options.Configure(opts...)
+
+	return &mta{
+		opts: options,
+	}
+}
+
+// Start ...
+func (m *mta) Start(ctx context.Context, ready server.ReadyFunc, run server.RunFunc) func() error {
+	return func() error {
+		l, err := net.Listen(Network, m.opts.Addr)
+		if err != nil {
+			return err
+		}
+
+		g, _ := group.WithContext(ctx)
+
+		for {
+			c, err := l.Accept()
+			if err != nil {
+				return err
+			}
+
+			s := NewSession(c)
+			g.Run(s.Serve())
+		}
+	}
+}

Diff for: smtp/session.go

@@ -0,0 +1,50 @@
+package smtp
+
+import (
+	"context"
+	"crypto/tls"
+	"fmt"
+	"net"
+	"net/textproto"
+	"sync"
+
+	"github.com/katallaxie/pkg/group"
+)
+
+// Session ...
+type Session struct {
+	// Text is the textproto.Conn of the connection.
+	Text *textproto.Conn
+	// keep a reference to the connection so it can be used to create a TLS
+	// connection later
+	conn net.Conn
+	// tls indicates whether the connection is already in TLS mode
+	tls bool
+
+	sync.Mutex
+}
+
+// NewSession...
+func NewSession(conn net.Conn) *Session {
+	s := new(Session)
+	s.Text = textproto.NewConn(conn)
+	s.conn = conn
+	_, s.tls = conn.(*tls.Conn)
+
+	return s
+}
+
+// Serve ...
+func (s *Session) Serve() group.RunFunc {
+	return func(ctx context.Context) {
+		for {
+			s.Text.PrintfLine("220 localhost ESMTP Service Ready")
+			l, err := s.Text.ReadLine()
+			if err != nil {
+				return
+			}
+
+			fmt.Println(l)
+		}
+	}
+}