implement

internal/postgres/client.go

@@ -0,0 +1,73 @@
+package postgres
+
+import (
+	"context"
+	"fmt"
+	"io"
+
+	"github.com/jackc/pgx/v5/pgxpool"
+	"golang.org/x/exp/slog"
+)
+
+type DatabaseStats struct {
+	MaxConnections      int32
+	TotalConnections    int32
+	AcquiredConnections int32
+	IdleConnections     int32
+}
+
+type Client interface {
+	io.Closer
+
+	Queue() QueueClient
+
+	GetStats() DatabaseStats
+}
+
+type Config struct {
+	MaxConns     int64
+	MaxIdleConns int64
+	MasterDSN    string
+}
+
+type client struct {
+	pool *pgxpool.Pool
+	log  *slog.Logger
+}
+
+func New(ctx context.Context, config Config, logger *slog.Logger) (*client, error) {
+	pgconfig, err := pgxpool.ParseConfig(config.MasterDSN)
+	if err != nil {
+		return nil, fmt.Errorf("parsing config: %w", err)
+	}
+
+	pool, err := pgxpool.NewWithConfig(ctx, pgconfig)
+	if err != nil {
+		return nil, fmt.Errorf("making new connection: %w", err)
+	}
+
+	return &client{
+		pool: pool,
+		log:  logger.With(slog.String("name", "db")),
+	}, nil
+}
+
+func (c *client) Close() error {
+	if c.pool == nil {
+		return nil
+	}
+
+	c.pool.Close()
+	return nil
+}
+
+func (c *client) GetStats() DatabaseStats {
+	stat := c.pool.Stat()
+
+	return DatabaseStats{
+		MaxConnections:      stat.MaxConns(),
+		TotalConnections:    stat.TotalConns(),
+		AcquiredConnections: stat.AcquiredConns(),
+		IdleConnections:     stat.IdleConns(),
+	}
+}