feat: add url shortner

2026-05-11 16:13:22 +05:30
parent f2889a5679
commit 5e0a484239
17 changed files with 1305 additions and 13 deletions
@@ -0,0 +1,131 @@
+package repository
+
+import (
+	"context"
+	"fmt"
+	"os"
+	"path/filepath"
+	"sort"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/jackc/pgx/v5/pgxpool"
+	"go.uber.org/zap"
+)
+
+type Postgres struct {
+	Pool   *pgxpool.Pool
+	logger *zap.Logger
+}
+
+func NewPostgres(ctx context.Context, uri string, logger *zap.Logger) (*Postgres, error) {
+	if uri == "" {
+		return nil, fmt.Errorf("postgres URI is empty")
+	}
+
+	cfg, err := pgxpool.ParseConfig(uri)
+	if err != nil {
+		return nil, fmt.Errorf("postgres parse config: %w", err)
+	}
+	cfg.MaxConns = 20
+	cfg.MinConns = 2
+	cfg.MaxConnLifetime = 30 * time.Minute
+	cfg.MaxConnIdleTime = 5 * time.Minute
+
+	pingCtx, cancel := context.WithTimeout(ctx, 10*time.Second)
+	defer cancel()
+
+	pool, err := pgxpool.NewWithConfig(pingCtx, cfg)
+	if err != nil {
+		return nil, fmt.Errorf("postgres connect: %w", err)
+	}
+	if err := pool.Ping(pingCtx); err != nil {
+		pool.Close()
+		return nil, fmt.Errorf("postgres ping: %w", err)
+	}
+
+	logger.Info("connected to Postgres")
+	return &Postgres{Pool: pool, logger: logger}, nil
+}
+
+func (p *Postgres) Close() {
+	if p == nil || p.Pool == nil {
+		return
+	}
+	p.Pool.Close()
+}
+
+// RunMigrations applies any *.up.sql files in dir that haven't been recorded
+// in schema_migrations yet, in lexical order. Tiny homegrown runner — no
+// external dependency. Down-migrations are not executed automatically.
+func (p *Postgres) RunMigrations(ctx context.Context, dir string) error {
+	if _, err := p.Pool.Exec(ctx, `
+		CREATE TABLE IF NOT EXISTS schema_migrations (
+			version    BIGINT PRIMARY KEY,
+			applied_at TIMESTAMPTZ NOT NULL DEFAULT now()
+		)`); err != nil {
+		return fmt.Errorf("create schema_migrations: %w", err)
+	}
+
+	files, err := filepath.Glob(filepath.Join(dir, "*.up.sql"))
+	if err != nil {
+		return fmt.Errorf("glob migrations: %w", err)
+	}
+	sort.Strings(files)
+
+	for _, f := range files {
+		version, err := parseMigrationVersion(f)
+		if err != nil {
+			p.logger.Warn("skipping unparseable migration filename", zap.String("file", f), zap.Error(err))
+			continue
+		}
+
+		var exists bool
+		if err := p.Pool.QueryRow(ctx,
+			`SELECT EXISTS(SELECT 1 FROM schema_migrations WHERE version = $1)`, version,
+		).Scan(&exists); err != nil {
+			return fmt.Errorf("check migration %d: %w", version, err)
+		}
+		if exists {
+			continue
+		}
+
+		sqlBytes, err := os.ReadFile(f)
+		if err != nil {
+			return fmt.Errorf("read %s: %w", f, err)
+		}
+
+		tx, err := p.Pool.Begin(ctx)
+		if err != nil {
+			return fmt.Errorf("begin tx for %s: %w", f, err)
+		}
+		if _, err := tx.Exec(ctx, string(sqlBytes)); err != nil {
+			_ = tx.Rollback(ctx)
+			return fmt.Errorf("apply %s: %w", f, err)
+		}
+		if _, err := tx.Exec(ctx, `INSERT INTO schema_migrations(version) VALUES ($1)`, version); err != nil {
+			_ = tx.Rollback(ctx)
+			return fmt.Errorf("record %s: %w", f, err)
+		}
+		if err := tx.Commit(ctx); err != nil {
+			return fmt.Errorf("commit %s: %w", f, err)
+		}
+
+		p.logger.Info("applied migration", zap.String("file", filepath.Base(f)), zap.Int64("version", version))
+	}
+	return nil
+}
+
+func parseMigrationVersion(path string) (int64, error) {
+	base := filepath.Base(path)
+	idx := strings.Index(base, "_")
+	if idx <= 0 {
+		return 0, fmt.Errorf("filename %q must start with <version>_", base)
+	}
+	v, err := strconv.ParseInt(base[:idx], 10, 64)
+	if err != nil {
+		return 0, fmt.Errorf("version prefix not an integer: %w", err)
+	}
+	return v, nil
+}