fork github.com/doug-martin

engine/engine.go

@@ -0,0 +1,89 @@
+package engine
+
+import (
+	"database/sql"
+	"fmt"
+
+	"github.com/lib/pq"
+
+	_ "github.com/denisenkom/go-mssqldb"
+	_ "github.com/go-sql-driver/mysql"
+	_ "github.com/mattn/go-sqlite3"
+
+	_ "git.fsdpf.net/go/db/v2/dialect/mysql"
+	_ "git.fsdpf.net/go/db/v2/dialect/postgres"
+	_ "git.fsdpf.net/go/db/v2/dialect/sqlite3"
+	_ "git.fsdpf.net/go/db/v2/dialect/sqlserver"
+
+	"git.fsdpf.net/go/db/v2"
+	"git.fsdpf.net/go/db/v2/internal/errors"
+)
+
+type Engine struct {
+	configs map[string]DBConfig
+	dbs     map[string]*sql.DB
+}
+
+var _engine *Engine
+
+func init() {
+	_engine = &Engine{
+		configs: make(map[string]DBConfig),
+		dbs:     make(map[string]*sql.DB),
+	}
+}
+
+func (e Engine) Connection(name string) *db.Database {
+	cfg, ok := e.configs[name]
+
+	if !ok {
+		panic(errors.New(fmt.Sprintf("Database connection %s not configured.", name)))
+	}
+
+	_db, ok := e.dbs[name]
+
+	if !ok {
+		_db = e.MakeConnection(cfg)
+		e.dbs[name] = _db
+	}
+
+	return db.New(cfg.Driver, _db)
+}
+
+func (e Engine) MakeConnection(cfg DBConfig) *sql.DB {
+	dsn := cfg.ToDSN()
+
+	switch cfg.Driver {
+	case "mysql":
+	case "sqlite3":
+	case "sqlserver":
+	case "postgres":
+		if url, err := pq.ParseURL(dsn); err == nil {
+			dsn = url
+		} else {
+			panic(err)
+		}
+	default:
+		panic(fmt.Sprintf("Unsupported driver: %s", cfg.Driver))
+	}
+
+	db, err := sql.Open(cfg.Driver, dsn)
+
+	if err != nil {
+		panic(err)
+	}
+
+	if err := db.Ping(); err != nil {
+		panic(err)
+	}
+
+	return db
+}
+
+func Open(cfgs map[string]DBConfig) *Engine {
+	for n, cfg := range cfgs {
+		_engine.configs[n] = cfg
+	}
+
+	return _engine
+}