feat: standard error handling

internal/controllers/v1/events/handlers.go

@@ -0,0 +1,58 @@
+package events
+
+import (
+	"math/rand"
+	"net/http"
+	"spotify-collab/internal/database"
+	"spotify-collab/internal/merrors"
+
+	"github.com/gin-gonic/gin"
+	"github.com/jackc/pgx/v5/pgxpool"
+)
+
+type EventHandler struct {
+	db *pgxpool.Pool
+}
+
+func Handler(db *pgxpool.Pool) *EventHandler {
+	return &EventHandler{
+		db: db,
+	}
+}
+
+func (e *EventHandler) CreateEvent(c *gin.Context) {
+	req, err := validateCreateEventReq(c)
+	if err != nil {
+		merrors.Validation(c, err.Error())
+		return
+	}
+
+	q := database.New(e.db)
+
+	eventCode := GenerateEventCode(6)
+
+	event, err := q.CreateEvent(c, database.CreateEventParams{
+		UserUuid:  req.UserUUID,
+		Name:      req.Name,
+		EventCode: eventCode,
+	})
+	if err != nil {
+		merrors.InternalServer(c, err.Error())
+	}
+
+	c.JSON(http.StatusOK, CreateEventRes{
+		CreatedAt: event.CreatedAt,
+		EventUUID: event.EventUuid,
+		Name:      event.Name,
+	})
+}
+
+var letters = []rune("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789")
+
+func GenerateEventCode(n int) string {
+	b := make([]rune, n)
+	for i := range b {
+		b[i] = letters[rand.Intn(len(letters))]
+	}
+	return string(b)
+}

internal/controllers/v1/events/models.go

@@ -0,0 +1,17 @@
+package events
+
+import (
+	"github.com/google/uuid"
+	"github.com/jackc/pgx/v5/pgtype"
+)
+
+type CreateEventReq struct {
+	UserUUID uuid.UUID `json:"user_uuid"`
+	Name     string    `json:"name"`
+}
+
+type CreateEventRes struct {
+	CreatedAt pgtype.Timestamptz `json:"created_at"`
+	EventUUID uuid.UUID          `json:"event_uuid"`
+	Name      string             `json:"name"`
+}

internal/controllers/v1/events/validators.go

@@ -0,0 +1,9 @@
+package events
+
+import "github.com/gin-gonic/gin"
+
+func validateCreateEventReq(c *gin.Context) (CreateEventReq, error) {
+	var req CreateEventReq
+	err := c.ShouldBindJSON(req)
+	return req, err
+}

internal/database/database.go

@@ -2,30 +2,29 @@ package database
 
 import (
 	"context"
-	"database/sql"
 	"fmt"
 	"log"
 	"os"
-	"strconv"
 	"time"
 
+	"github.com/jackc/pgx/v5/pgxpool"
 	_ "github.com/jackc/pgx/v5/stdlib"
 	_ "github.com/joho/godotenv/autoload"
 )
 
 // Service represents a service that interacts with a database.
-type Service interface {
-	// Health returns a map of health status information.
-	// The keys and values in the map are service-specific.
-	Health() map[string]string
-
-	// Close terminates the database connection.
-	// It returns an error if the connection cannot be closed.
-	Close() error
-}
-
-type service struct {
-	db *sql.DB
+// type Service interface {
+// 	// Health returns a map of health status information.
+// 	// The keys and values in the map are service-specific.
+// 	Health() map[string]string
+
+// 	// Close terminates the database connection.
+// 	// It returns an error if the connection cannot be closed.
+// 	Close() error
+// }
+
+type Service struct {
+	Db *pgxpool.Pool
 }
 
 var (
@@ -35,35 +34,34 @@ var (
 	port       = os.Getenv("DB_PORT")
 	host       = os.Getenv("DB_HOST")
 	schema     = os.Getenv("DB_SCHEMA")
-	dbInstance *service
+	dbInstance *pgxpool.Pool
 )
 
-func NewService() Service {
+func NewService() *pgxpool.Pool {
 	// Reuse Connection
 	if dbInstance != nil {
 		return dbInstance
 	}
 	connStr := fmt.Sprintf("postgres://%s:%s@%s:%s/%s?sslmode=disable&search_path=%s", username, password, host, port, database, schema)
-	db, err := sql.Open("pgx", connStr)
+	db, err := pgxpool.New(context.Background(), connStr)
 	if err != nil {
 		log.Fatal(err)
 	}
-	dbInstance = &service{
-		db: db,
-	}
+	dbInstance = db
 	return dbInstance
 }
 
 // Health checks the health of the database connection by pinging the database.
 // It returns a map with keys indicating various health statistics.
-func (s *service) Health() map[string]string {
+func (s *Service) Health() map[string]string {
 	ctx, cancel := context.WithTimeout(context.Background(), 1*time.Second)
 	defer cancel()
 
 	stats := make(map[string]string)
 
 	// Ping the database
-	err := s.db.PingContext(ctx)
+	// err := s.db.PingContext(ctx)
+	err := s.Db.Ping(ctx)
 	if err != nil {
 		stats["status"] = "down"
 		stats["error"] = fmt.Sprintf("db down: %v", err)
@@ -76,31 +74,32 @@ func (s *service) Health() map[string]string {
 	stats["message"] = "It's healthy"
 
 	// Get database stats (like open connections, in use, idle, etc.)
-	dbStats := s.db.Stats()
-	stats["open_connections"] = strconv.Itoa(dbStats.OpenConnections)
-	stats["in_use"] = strconv.Itoa(dbStats.InUse)
-	stats["idle"] = strconv.Itoa(dbStats.Idle)
-	stats["wait_count"] = strconv.FormatInt(dbStats.WaitCount, 10)
-	stats["wait_duration"] = dbStats.WaitDuration.String()
-	stats["max_idle_closed"] = strconv.FormatInt(dbStats.MaxIdleClosed, 10)
-	stats["max_lifetime_closed"] = strconv.FormatInt(dbStats.MaxLifetimeClosed, 10)
-
-	// Evaluate stats to provide a health message
-	if dbStats.OpenConnections > 40 { // Assuming 50 is the max for this example
-		stats["message"] = "The database is experiencing heavy load."
-	}
-
-	if dbStats.WaitCount > 1000 {
-		stats["message"] = "The database has a high number of wait events, indicating potential bottlenecks."
-	}
-
-	if dbStats.MaxIdleClosed > int64(dbStats.OpenConnections)/2 {
-		stats["message"] = "Many idle connections are being closed, consider revising the connection pool settings."
-	}
-
-	if dbStats.MaxLifetimeClosed > int64(dbStats.OpenConnections)/2 {
-		stats["message"] = "Many connections are being closed due to max lifetime, consider increasing max lifetime or revising the connection usage pattern."
-	}
+	// dbStats := s.db.Stats()
+	_ = s.Db.Stat()
+	// stats["open_connections"] = strconv.Itoa(dbStats.OpenConnections)
+	// stats["in_use"] = strconv.Itoa(dbStats.InUse)
+	// stats["idle"] = strconv.Itoa(dbStats.Idle)
+	// stats["wait_count"] = strconv.FormatInt(dbStats.WaitCount, 10)
+	// stats["wait_duration"] = dbStats.WaitDuration.String()
+	// stats["max_idle_closed"] = strconv.FormatInt(dbStats.MaxIdleClosed, 10)
+	// stats["max_lifetime_closed"] = strconv.FormatInt(dbStats.MaxLifetimeClosed, 10)
+
+	// // Evaluate stats to provide a health message
+	// if dbStats.OpenConnections > 40 { // Assuming 50 is the max for this example
+	// 	stats["message"] = "The database is experiencing heavy load."
+	// }
+
+	// if dbStats.WaitCount > 1000 {
+	// 	stats["message"] = "The database has a high number of wait events, indicating potential bottlenecks."
+	// }
+
+	// if dbStats.MaxIdleClosed > int64(dbStats.OpenConnections)/2 {
+	// 	stats["message"] = "Many idle connections are being closed, consider revising the connection pool settings."
+	// }
+
+	// if dbStats.MaxLifetimeClosed > int64(dbStats.OpenConnections)/2 {
+	// 	stats["message"] = "Many connections are being closed due to max lifetime, consider increasing max lifetime or revising the connection usage pattern."
+	// }
 
 	return stats
 }
@@ -109,7 +108,7 @@ func (s *service) Health() map[string]string {
 // It logs a message indicating the disconnection from the specific database.
 // If the connection is successfully closed, it returns nil.
 // If an error occurs while closing the connection, it returns the error.
-func (s *service) Close() error {
+func (s *Service) Close() {
 	log.Printf("Disconnected from database: %s", database)
-	return s.db.Close()
+	s.Db.Close()
 }

internal/database/migrations/000003_create_playlists_table.up.sql

@@ -5,6 +5,6 @@ CREATE TABLE public.playlists (
 	created_at timestamptz DEFAULT now() NOT NULL,
 	updated_at timestamptz DEFAULT now() NOT NULL,
 	CONSTRAINT playlists_pk PRIMARY KEY (playlist_id),
-	CONSTRAINT playlists_unique UNIQUE (name),
+	CONSTRAINT playlists_unique UNIQUE (event_uuid, name),
 	CONSTRAINT playlists_events_fk FOREIGN KEY (event_uuid) REFERENCES public.events(event_uuid) ON DELETE CASCADE ON UPDATE CASCADE
 );

internal/database/queries/events.sql

@@ -1,6 +1,6 @@
 -- name: CreateEvent :one
-INSERT INTO events (user_uuid, event_uuid, name, event_code)
-VALUES ($1, $2, $3, $4)
+INSERT INTO events (user_uuid, name, event_code)
+VALUES ($1, $2, $3)
 RETURNING *;
 
 -- name: GetAllEvents :many
@@ -18,6 +18,11 @@ SELECT event_uuid
 FROM events
 WHERE name = $1;
 
+-- name: GetEventUUIDByCode :one
+Select event_uuid
+FROM events
+WHERE event_code = $1;
+
 -- name: UpdateEventName :one
 UPDATE events
 SET name = $1

internal/database/queries/playlists.sql

@@ -13,12 +13,18 @@ SELECT *
 FROM playlists
 WHERE event_uuid = $1 AND playlist_id = $2;
 
-
 -- name: GetPlaylistUUIDByName :one
 SELECT playlist_id 
 FROM playlists
 WHERE event_uuid = $1 AND name = $2;
 
+-- name: GetPlaylistUUIDByEventUUID :one
+Select playlist_id
+FROM playlists
+WHERE event_uuid = $1
+ORDER BY created_at desc
+Limit 1;
+
 -- name: UpdatePlaylistName :one
 UPDATE playlists
 SET name = $1

internal/merrors/conflict_409.go

@@ -0,0 +1,25 @@
+package merrors
+
+import (
+	"net/http"
+
+	"spotify-collab/internal/utils"
+
+	"github.com/gin-gonic/gin"
+)
+
+/* -------------------------------------------------------------------------- */
+/*                                Conflict 409                                */
+/* -------------------------------------------------------------------------- */
+
+func Conflict(ctx *gin.Context, err string) {
+	var res utils.BaseResponse
+	var smerror utils.Error
+	errorCode := http.StatusConflict
+	smerror.Code = errorCode
+	smerror.Type = errorType.conflict
+	smerror.Message = err
+	res.Error = smerror
+	ctx.JSON(errorCode, res)
+	ctx.Abort()
+}