auth: added Authentication using JWT token

cmd/api/auth.go

@@ -2,8 +2,10 @@ package main
 
 import (
 	"net/http"
+	"time"
 
 	"github.com/gin-gonic/gin"
+	"github.com/golang-jwt/jwt/v4"
 	"github.com/kunalkumar-1/Evently/internals/database"
 	"golang.org/x/crypto/bcrypt"
 )
@@ -14,6 +16,15 @@ type registerRequest struct {
 	Name     string `json:"name" binding:"required,min=3,max=50"`
 }
 
+type loginRequest struct {
+	Email    string `json:"email" binding:"required,email"`
+	Password string `json:"password" binding:"required,min=8"`
+}
+
+type loginResponse struct {
+	Token string `json:"token"`
+}
+
 func (app *application) registerUser(c *gin.Context) {
 	var register registerRequest
 
@@ -49,3 +60,51 @@ func (app *application) registerUser(c *gin.Context) {
 
 	c.JSON(http.StatusCreated, user)
 }
+
+func (app *application) login(c *gin.Context) {
+	var auth loginRequest
+	if err := c.ShouldBindJSON(&auth); err != nil {
+		c.JSON(http.StatusBadRequest, gin.H{
+			"error": err.Error(),
+		})
+		return
+	}
+
+	existingUser, err := app.models.Users.GetByEmail(auth.Email)
+	if existingUser == nil {
+		c.JSON(http.StatusUnauthorized, gin.H{
+			"error": "Invlid Email or Password",
+		})
+		return
+	}
+	if err != nil {
+		c.JSON(http.StatusUnauthorized, gin.H{
+			"error": err.Error(),
+		})
+		return
+	}
+	err = bcrypt.CompareHashAndPassword([]byte(existingUser.Password), []byte(auth.Password))
+	if err != nil {
+		c.JSON(http.StatusUnauthorized, gin.H{
+			"error": "Invalid Email or Password",
+		})
+		return
+	}
+
+	token := jwt.NewWithClaims(jwt.SigningMethodHS256, jwt.MapClaims{
+		"UserId": existingUser.Id,
+		"expr":   time.Now().Add(time.Hour * 72).Unix(),
+	})
+
+	tokenString, err := token.SignedString([]byte(app.jwtSecret))
+	if err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{
+			"error": "Error Generating token",
+		})
+		return
+	}
+
+	c.JSON(http.StatusOK, loginResponse{
+		Token: tokenString,
+	})
+}

cmd/api/events.go

@@ -228,14 +228,16 @@ func (app *application) getAttendeesForEvent(c *gin.Context) {
 		})
 		return
 	}
-	users, err := app.models.Attendees.GetAttendeeByEvent(id)
+
+	events, err := app.models.Attendees.GetAttendeeByEvent(id) //get attendees for event
 	if err != nil {
 		c.JSON(http.StatusInternalServerError, gin.H{
 			"error": "failed to retrieve Attendees for events",
 		})
 		return
 	}
-	c.JSON(http.StatusOK, users)
+
+	c.JSON(http.StatusOK, events)
 }
 
 func (app *application) deleteAttendeeFromEvent(c *gin.Context) {

cmd/api/routes.go

@@ -16,12 +16,13 @@ func (app *application) routes() http.Handler {
 		v1.GET("/events/:id", app.getEvent)                                     // get event by id
 		v1.PUT("/events/:id", app.updateEvent)                                  // update event by id
 		v1.DELETE("/events/:id", app.deleteEvent)                               //delete the event by id
-		v1.GET("/events/:id/attendees/:userId", app.getAttendeesForEvent)       // get attendee to event
-		v1.POST("/events/:id/attendees/:userId", app.addAttendeeToEvent)        // add attendee to event
+		v1.POST("/events/:id/attendees/:userId", app.addAttendeeToEvent)        // get attendee to event
+		v1.GET("/events/:id/attendees/", app.getAttendeesForEvent)              // add attendee to event
 		v1.DELETE("/events/:id/attendees/:userId", app.deleteAttendeeFromEvent) //delete attendee from event
-		v1.GET("/events/:id/attendees", app.getEventsByAttendee)                //get attendees for event
+		v1.GET("/attendees/:id/events", app.getEventsByAttendee)                //get attendees for event
+		v1.POST("/auth/register", app.registerUser)                             // register user
+		v1.POST("/auth/login", app.login)
 
-		v1.POST("/auth/register", app.registerUser) // register user
 	}
 
 	return r

go.mod

@@ -38,6 +38,7 @@ require (
 
 require (
 	github.com/gin-gonic/gin v1.10.1
+	github.com/golang-jwt/jwt/v4 v4.5.2
 	github.com/hashicorp/errwrap v1.1.0 // indirect
 	github.com/hashicorp/go-multierror v1.1.1 // indirect
 	github.com/joho/godotenv v1.5.1

go.sum

@@ -25,6 +25,8 @@ github.com/go-playground/validator/v10 v10.20.0 h1:K9ISHbSaI0lyB2eWMPJo+kOS/FBEx
 github.com/go-playground/validator/v10 v10.20.0/go.mod h1:dbuPbCMFw/DrkbEynArYaCwl3amGuJotoKCe95atGMM=
 github.com/goccy/go-json v0.10.2 h1:CrxCmQqYDkv1z7lO7Wbh2HN93uovUHgrECaO5ZrCXAU=
 github.com/goccy/go-json v0.10.2/go.mod h1:6MelG93GURQebXPDq3khkgXZkazVtN9CRI+MGFi0w8I=
+github.com/golang-jwt/jwt/v4 v4.5.2 h1:YtQM7lnr8iZ+j5q71MGKkNw9Mn7AjHM68uc9g5fXeUI=
+github.com/golang-jwt/jwt/v4 v4.5.2/go.mod h1:m21LjoU+eqJr34lmDMbreY2eSTRJ1cv77w39/MY0Ch0=
 github.com/golang-migrate/migrate/v4 v4.18.3 h1:EYGkoOsvgHHfm5U/naS1RP/6PL/Xv3S4B/swMiAmDLs=
 github.com/golang-migrate/migrate/v4 v4.18.3/go.mod h1:99BKpIi6ruaaXRM1A77eqZ+FWPQ3cfRa+ZVy5bmWMaY=
 github.com/google/go-cmp v0.6.0 h1:ofyhxvXcZhMsU5ulbFiLKl/XBFqE1GSq7atu8tAmTRI=

internals/database/users.go

@@ -27,13 +27,12 @@ func (u *UserModel) Insert(user *User) error {
 
 }
 
-func (u *UserModel) Get(id int) (*User, error) {
+func (u *UserModel) getUser(query string, args ...interface{}) (*User, error) {
 	ctx, cancel := context.WithTimeout(context.Background(), 3*time.Second)
 	defer cancel()
 
-	query := `SELECT * FROM users WHERE id = $1`
 	var user User
-	err := u.Db.QueryRowContext(ctx, query, id).Scan(&user.Id, &user.Name, &user.Email, &user.Password)
+	err := u.Db.QueryRowContext(ctx, query, args...).Scan(&user.Id, &user.Name, &user.Email, &user.Password)
 	if err != nil {
 		if err == sql.ErrNoRows {
 			return nil, nil
@@ -42,3 +41,30 @@ func (u *UserModel) Get(id int) (*User, error) {
 	}
 	return &user, nil
 }
+
+func (u *UserModel) Get(id int) (*User, error) {
+	query := `SELECT * FROM users WHERE id = $1`
+	return u.getUser(query, id)
+}
+
+func (u *UserModel) GetByEmail(email string) (*User, error) {
+	query := `SELECT * FROM users WHERE email = $1`
+	return u.getUser(query, email)
+}
+
+// func (u *UserModel) GetByEmail(email string) (*User, error) {
+// 	ctx, cancel := context.WithTimeout(context.Background(), 3*time.Second)
+// 	defer cancel()
+
+// 	query := `SELECT * FROM users WHERE email = $1`
+
+// 	var user User
+// 	err := u.Db.QueryRowContext(ctx, query, email).Scan(&user.Id, &user.Name, &user.Email, &user.Password)
+// 	if err != nil {
+// 		if err == sql.ErrNoRows {
+// 			return nil, nil
+// 		}
+// 		return nil, err
+// 	}
+// 	return &user, nil
+// }