initial pool creation

BACKEND_BLUEPRINT.md

@@ -71,6 +71,19 @@
 - Keep SQL in context directories (`query.sql`, `models.sql` style)
 - Service layer composes multiple repositories when needed
 
+### Work in Progress Snapshot
+
+- `sqlc.yaml` is now configured for PostgreSQL with schema from `migrations/*.sql`
+- First bounded context added: `internal/db/users`
+- Current users SQLC artifacts generated:
+  - `db.go`, `models.go`, `queries.sql.go`, `querier.go`
+- Current SQLC generation options in use:
+  - `sql_package: pgx/v5`
+  - `emit_interface: true` (generated `Querier` interface)
+  - `emit_json_tags: false` (can be revisited if API structs are returned directly)
+- Initial queries implemented for users: `GetUser`, `CreateUser`, `DeleteUser`
+- DB pool wiring into `cmd/api` and service construction is planned next
+
 ---
 
 ## Testing Approach (Beginner-Friendly)
@@ -80,6 +93,14 @@
 - Unit tests for pure service logic (no DB)
 - Integration tests for SQLC repositories with real Postgres via Docker
 
+### DB Interface Testing (via SQLC `Querier`)
+
+- Treat generated SQLC interfaces (e.g. `usersdb.Querier`) as service dependencies
+- For service unit tests, provide a fake/mock implementation of `Querier`
+- Focus unit tests on business rules, branching, and error mapping (not SQL behavior)
+- Keep SQL correctness in integration tests against real Postgres
+- This split gives fast unit tests plus high-confidence DB integration coverage
+
 ### Phase 2
 
 - HTTP handler tests with `httptest`

cmd/api/main.go

@@ -1,12 +1,31 @@
 package main
 
 import (
+	"context"
 	"log"
+	"time"
 
 	"git.kanopo.dev/rhythm/rhythm-backend/internal/config"
+	"github.com/jackc/pgx/v5/pgxpool"
 )
 
 func main() {
 	cfg := config.Load()
-	log.Println(cfg.DbUrl)
+	ctx := context.Background()
+	pool, err := pgxpool.New(ctx, cfg.DbUrl)
+	if err != nil {
+		log.Fatalf("Error creatin the db pool:%v\n", err.Error())
+	}
+	defer pool.Close()
+
+	{
+		ctx, cancel := context.WithTimeout(ctx, time.Second*5)
+		defer cancel()
+		if err := pool.Ping(ctx); err != nil {
+			log.Fatalf("ping to db failed %v", err.Error())
+		}
+		log.Printf("successfully connected to database")
+
+	}
+
 }

go.mod

@@ -10,5 +10,7 @@ require (
 require (
 	github.com/jackc/pgpassfile v1.0.0 // indirect
 	github.com/jackc/pgservicefile v0.0.0-20240606120523-5a60cdf6a761 // indirect
+	github.com/jackc/puddle/v2 v2.2.2 // indirect
+	golang.org/x/sync v0.17.0 // indirect
 	golang.org/x/text v0.29.0 // indirect
 )

internal/config/config.go

@@ -21,7 +21,7 @@ func Load() Config {
 		host := getEnv("DB_HOST")
 
 		// postgres://admin:admin@localhost:5432/admin_db
-		dbUrl = fmt.Sprintf("postgres://%v:%v@%v:%v/%v?sslmode=disabled", username, password, host, port, name)
+		dbUrl = fmt.Sprintf("postgres://%v:%v@%v:%v/%v?sslmode=disable", username, password, host, port, name)
 	}
 
 	cfg := Config{
@@ -35,7 +35,7 @@ func Load() Config {
 func getEnv(key string) string {
 	v := os.Getenv(key)
 	if v == "" {
-		log.Fatalln("The env variable %v is not defined and the applciation can not operate without", key)
+		log.Fatalf("The env variable %v is not defined and the applciation can not operate without\n", key)
 	}
 	return v
 }