wip

ntpdb/dbconn.go

@@ -0,0 +1,75 @@
+package ntpdb
+
+import (
+	"database/sql"
+	"database/sql/driver"
+	"fmt"
+	"log"
+	"os"
+	"time"
+
+	"github.com/go-sql-driver/mysql"
+	"gopkg.in/yaml.v3"
+)
+
+type DBConfig struct {
+	DSN  string `default:"" flag:"dsn" usage:"Database DSN"`
+	User string `default:"" flag:"user"`
+	Pass string `default:"" flag:"pass"`
+}
+
+func OpenDB(configFile string) (*sql.DB, error) {
+
+	dbconn := sql.OpenDB(Driver{CreateConnectorFunc: createConnector(configFile)})
+
+	dbconn.SetConnMaxLifetime(time.Minute * 3)
+	dbconn.SetMaxOpenConns(10)
+	dbconn.SetMaxIdleConns(5)
+
+	err := dbconn.Ping()
+	if err != nil {
+		log.Printf("Could not connect to database: %s", err)
+		return nil, err
+	}
+
+	return dbconn, nil
+}
+
+func createConnector(configFile string) CreateConnectorFunc {
+	return func() (driver.Connector, error) {
+
+		dbFile, err := os.Open(configFile)
+		if err != nil {
+			return nil, err
+		}
+
+		dec := yaml.NewDecoder(dbFile)
+
+		cfg := DBConfig{}
+
+		err = dec.Decode(&cfg)
+		if err != nil {
+			return nil, err
+		}
+
+		dsn := cfg.DSN
+		if len(dsn) == 0 {
+			return nil, fmt.Errorf("--database.dsn flag or DATABASE_DSN environment variable required")
+		}
+
+		dbcfg, err := mysql.ParseDSN(dsn)
+		if err != nil {
+			return nil, err
+		}
+
+		if user := cfg.User; len(user) > 0 && err == nil {
+			dbcfg.User = user
+		}
+
+		if pass := cfg.Pass; len(pass) > 0 && err == nil {
+			dbcfg.Passwd = pass
+		}
+
+		return mysql.NewConnector(dbcfg)
+	}
+}