🏗️ Login package refactor

login/check_authorization.go

@@ -4,34 +4,40 @@ import (
 	"crypto/hmac"
 	"crypto/sha256"
 	"encoding/hex"
-	"fmt"
+	"errors"
+	"net/url"
+	"strconv"
 )
 
+var ErrUserNotDefined = errors.New("user is not defined")
+
 // CheckAuthorization verify the authentication and the integrity of the data
 // received by comparing the received hash parameter with the hexadecimal
 // representation of the HMAC-SHA-256 signature of the data-check-string with the
 // SHA256 hash of the bot's token used as a secret key.
-func (user *User) CheckAuthorization(botToken string) (bool, error) {
-	dataCheckString := fmt.Sprint(
-		"auth_date=", user.AuthDate.Unix(),
-		"\n", "first_name=", user.FirstName,
-		// Eliminate 'hash' to avoid recursion and incorrect data validation.
-		"\n", "id=", user.ID,
-	)
+func (app *App) CheckAuthorization(user *User) (bool, error) {
+	if user == nil {
+		return false, ErrUserNotDefined
+	}
+
+	dataCheck := make(url.Values)
+	dataCheck.Add(KeyAuthDate, string(user.AuthDate))
+	dataCheck.Add(KeyFirstName, user.FirstName)
+	dataCheck.Add(KeyID, strconv.Itoa(user.ID))
 
 	// Add optional values if exist
 	if user.LastName != "" {
-		dataCheckString += fmt.Sprint("\n", "last_name=", user.LastName)
+		dataCheck.Add(KeyLastName, user.LastName)
 	}
 	if user.PhotoURL != "" {
-		dataCheckString += fmt.Sprint("\n", "photo_url=", user.PhotoURL)
+		dataCheck.Add(KeyPhotoURL, user.PhotoURL)
 	}
 	if user.Username != "" {
-		dataCheckString += fmt.Sprint("\n", "username=", user.Username)
+		dataCheck.Add(KeyUsername, user.Username)
 	}
 
-	secretKey := sha256.Sum256([]byte(botToken))
+	secretKey := sha256.Sum256([]byte(app.SecretKey))
 	hash := hmac.New(sha256.New, secretKey[0:])
-	_, err := hash.Write([]byte(dataCheckString))
+	_, err := hash.Write([]byte(dataCheck.Encode()))
 	return hex.EncodeToString(hash.Sum(nil)) == user.Hash, err
 }

login/constants.go

@@ -0,0 +1,11 @@
+package login
+
+const (
+	KeyAuthDate  = "auth_date"
+	KeyFirstName = "first_name"
+	KeyHash      = "hash"
+	KeyID        = "id"
+	KeyLastName  = "last_name"
+	KeyPhotoURL  = "photo_url"
+	KeyUsername  = "username"
+)

login/new.go

@@ -1,41 +1,11 @@
 package login
 
-import (
-	"net/url"
-	"strconv"
-	"time"
-)
-
-// User contains data about authenticated user.
-type User struct {
-	AuthDate  time.Time `json:"auth_date"`
-	FirstName string    `json:"first_name"`
-	Hash      string    `json:"hash"`
-	ID        int       `json:"id"`
-	LastName  string    `json:"last_name,omitempty"`
-	PhotoURL  string    `json:"photo_url,omitempty"`
-	Username  string    `json:"username,omitempty"`
+// App represents a widget which get and validate users authorizations.
+type App struct {
+	SecretKey string
 }
 
-// New create User structure from input url.Values.
-func New(src url.Values) (*User, error) {
-	authDate, err := strconv.Atoi(src.Get("auth_date"))
-	if err != nil {
-		return nil, err
-	}
-
-	id, err := strconv.Atoi(src.Get("id"))
-	if err != nil {
-		return nil, err
-	}
-
-	return &User{
-		AuthDate:  time.Unix(int64(authDate), 0),
-		FirstName: src.Get("first_name"),
-		Hash:      src.Get("hash"),
-		ID:        id,
-		LastName:  src.Get("last_name"),
-		PhotoURL:  src.Get("photo_url"),
-		Username:  src.Get("username"),
-	}, nil
+// New create new app widget for validate authorizations with bot token as secret key.
+func New(botToken string) *App {
+	return &App{SecretKey: botToken}
 }

login/parse_user.go

@@ -0,0 +1,40 @@
+package login
+
+import (
+	"net/url"
+	"strconv"
+)
+
+// User contains data about authenticated user.
+type User struct {
+	AuthDate  int64  `json:"auth_date"`
+	FirstName string `json:"first_name"`
+	Hash      string `json:"hash"`
+	ID        int    `json:"id"`
+	LastName  string `json:"last_name,omitempty"`
+	PhotoURL  string `json:"photo_url,omitempty"`
+	Username  string `json:"username,omitempty"`
+}
+
+// ParseUser create User structure from input url.Values.
+func ParseUser(src url.Values) (*User, error) {
+	authDate, err := strconv.Atoi(src.Get(KeyAuthDate))
+	if err != nil {
+		return nil, err
+	}
+
+	id, err := strconv.Atoi(src.Get(KeyID))
+	if err != nil {
+		return nil, err
+	}
+
+	return &User{
+		AuthDate:  int64(authDate),
+		FirstName: src.Get(KeyFirstName),
+		Hash:      src.Get(KeyHash),
+		ID:        id,
+		LastName:  src.Get(KeyLastName),
+		PhotoURL:  src.Get(KeyPhotoURL),
+		Username:  src.Get(KeyUsername),
+	}, nil
+}

login/utils.go

@@ -0,0 +1,28 @@
+package login
+
+import (
+	"fmt"
+	"time"
+)
+
+// FullName return user first name only or full name if last name is present.
+func (user *User) FullName() string {
+	if user == nil {
+		return ""
+	}
+
+	if user.LastName != "" {
+		return fmt.Sprintln(user.FirstName, user.LastName)
+	}
+
+	return user.FirstName
+}
+
+// AuthTime convert AuthDate field into time.Time.
+func (user *User) AuthTime() time.Time {
+	if user == nil {
+		return time.Time{}
+	}
+
+	return time.Unix(user.AuthDate, 0)
+}