first commit

dataBase.go

@@ -0,0 +1,223 @@
+package main
+
+import (
+	"context"
+	"database/sql"
+	"encoding/hex"
+	"fmt"
+	"github.com/pkg/errors"
+	"math/rand"
+	"time"
+
+	_ "github.com/lib/pq"
+)
+
+func init() {
+	rand.Seed(time.Now().UnixNano())
+}
+
+type dbLayer struct {
+	db *sql.DB
+}
+
+func connectToDataBase(host string, port uint32, user string, password string, dbName string) (*dbLayer, error) {
+	db, err := sql.Open("postgres",
+		fmt.Sprintf("host=%s port=%d user=%s password=%s dbname=%s sslmode=disable",
+			host, port, user, password, dbName,
+		),
+	)
+
+	if err != nil {
+		return nil, errors.Wrap(err, "Failed to connect to database")
+	}
+
+	return &dbLayer{
+		db: db,
+	}, nil
+}
+
+func (db *dbLayer) execInTransaction(ctx context.Context, query string, args ...interface{}) error {
+	tx, err := db.db.BeginTx(ctx, &sql.TxOptions{})
+	if err != nil {
+		return errors.Wrap(err, "Failed to begin transaction")
+	}
+
+	getLogger(ctx).Debugf("[Run sql query]: %s, [%v]", query, args)
+
+	_, err = tx.ExecContext(ctx, query, args...)
+	if err != nil {
+		_ = tx.Rollback()
+
+		return errors.Wrapf(err, "Failed to run db query [%s] [%v]", query, args)
+	}
+
+	err = tx.Commit()
+	if err != nil {
+		return errors.Wrap(err, "Failed to commit transaction")
+	}
+
+	return nil
+}
+
+type Player struct {
+	id             string
+	name           string
+	lastOnline     time.Time
+	onlineDuration time.Duration
+	deaths         int
+	level          int
+}
+
+func fetchPlayer(r *sql.Rows, p *Player) error {
+	var (
+		err            error
+		lastOnline     string
+		onlineDuration int
+	)
+
+	err = r.Scan(&p.id, &p.name, &lastOnline, &onlineDuration, &p.deaths, &p.level)
+	if err != nil {
+		return errors.Wrap(err, "Failed to fetch data base")
+	}
+
+	p.lastOnline, err = time.Parse(time.RFC3339, lastOnline)
+	if err != nil {
+		return errors.Wrapf(err, "Failed to parse date [%s]", lastOnline)
+	}
+
+	p.onlineDuration = time.Second * time.Duration(onlineDuration)
+
+	return nil
+}
+
+func (db *dbLayer) getPlayers(ctx context.Context) ([]Player, error) {
+	var players []Player
+
+	query := "SELECT id, name, last_login, online_duration, deaths, level FROM players"
+
+	rows, err := db.db.QueryContext(ctx, query)
+	if err != nil {
+		return nil, errors.Wrapf(err, "Failed to run db query [%s]", query)
+	}
+
+	defer rows.Close()
+
+	for rows.Next() {
+		p := Player{}
+
+		err = fetchPlayer(rows, &p)
+		if err != nil {
+			return nil, err
+		}
+
+		players = append(players, p)
+	}
+
+	return players, nil
+}
+
+func (db *dbLayer) getPlayerByID(ctx context.Context, id string) (*Player, error) {
+	query := "SELECT id, name, last_login, online_duration, deaths, level FROM players WHERE id = $1"
+
+	rows, err := db.db.QueryContext(ctx, query, id)
+	if err != nil {
+		return nil, errors.Wrapf(err, "Failed to run db query [%s]", query)
+	}
+
+	defer rows.Close()
+
+	if rows.Next() {
+		var p Player
+
+		err = fetchPlayer(rows, &p)
+		if err != nil {
+			return nil, err
+		}
+
+		return &p, nil
+	}
+
+	return nil, nil
+}
+
+func (db *dbLayer) getPlayerByName(ctx context.Context, name string) (*Player, error) {
+	query := "SELECT id, name, last_login, online_duration, deaths, level FROM players WHERE name = $1 LIMIT 1"
+
+	rows, err := db.db.QueryContext(ctx, query, name)
+	if err != nil {
+		return nil, errors.Wrapf(err, "Failed to run db query [%s]", query)
+	}
+
+	defer rows.Close()
+
+	if rows.Next() {
+		var p Player
+
+		err = fetchPlayer(rows, &p)
+		if err != nil {
+			return nil, err
+		}
+
+		return &p, nil
+	}
+
+	return nil, nil
+}
+
+func (db *dbLayer) createPlayer(ctx context.Context, name string, lastOnline time.Time) (*Player, error) {
+	id := uuid()
+
+	err := db.execInTransaction(ctx, "INSERT INTO players (id, name, last_login) VALUES ($1, $2, $3)", id, name, lastOnline.Format(time.RFC3339))
+
+	if err != nil {
+		return nil, err
+	}
+
+	return &Player{
+		id:         id,
+		name:       name,
+		lastOnline: lastOnline,
+	}, nil
+}
+
+func (db *dbLayer) increasePlayerOnlineDuration(ctx context.Context, playerID string, d time.Duration) error {
+	onlineDurationSecond := int(d / time.Second)
+	if onlineDurationSecond == 0 {
+		return nil
+	}
+
+	return db.execInTransaction(ctx, "UPDATE players SET online_duration = online_duration + $2 WHERE id = $1", playerID, onlineDurationSecond)
+}
+
+func (db *dbLayer) updatePlayerLastOnline(ctx context.Context, playerID string, lastOnline time.Time) error {
+	return db.execInTransaction(ctx, "UPDATE players SET last_login = $2 WHERE id = $1", playerID, lastOnline.Format(time.RFC3339))
+}
+
+func (db *dbLayer) increasePlayerDeath(ctx context.Context, playerID string, deaths int) error {
+	return db.execInTransaction(ctx, "UPDATE players SET deaths = deaths + $2 WHERE id = $1", playerID, deaths)
+}
+
+func (db *dbLayer) increasePlayerEntryKills(ctx context.Context, playerID string, entity string, count int) error {
+	return db.execInTransaction(ctx,
+		"INSERT INTO killings (player_id, entity, count) VALUES ($1, $2, $3) ON CONFLICT (player_id, entity) DO UPDATE SET count = killings.count + excluded.count",
+		playerID, entity, count,
+	)
+}
+
+func (db *dbLayer) updatePlayerLevel(ctx context.Context, playerID string, level int) error {
+	return db.execInTransaction(ctx, "UPDATE players SET level = $2 WHERE id = $1", playerID, level)
+}
+
+func uuid() string {
+	token := make([]byte, 18)
+	rand.Read(token)
+	result := make([]byte, 36)
+	hex.Encode(result, token)
+
+	result[8] = 45
+	result[13] = 45
+	result[18] = 45
+	result[23] = 45
+
+	return string(result)
+}