Added initial support for MySQL databases

cmd/data/db.go

@@ -0,0 +1,34 @@
+package data
+
+import (
+	"database/sql"
+	"fmt"
+
+	"github.com/go-sql-driver/mysql"
+)
+
+type DB struct {
+	*sql.DB
+}
+
+func OpenDB(dbName string) (*DB, error) {
+	var err error
+	db := DB{DB: &sql.DB{}}
+
+	cfg := mysql.NewConfig()
+	cfg.DBName = dbName
+	cfg.User, cfg.Passwd, err = getCredentials()
+	if err != nil {
+		return nil, fmt.Errorf("error: user credentials for DB could not be read: %v", err)
+	}
+
+	db.DB, err = sql.Open("mysql", cfg.FormatDSN())
+	if err != nil {
+		return nil, fmt.Errorf("error: DB could not be opened: %v", err)
+	}
+	if err = db.Ping(); err != nil {
+		return nil, fmt.Errorf("error: DB could not be reached: %v", err)
+	}
+
+	return &db, nil
+}

cmd/data/helpers.go

@@ -0,0 +1,52 @@
+package data
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+	"strings"
+	"syscall"
+
+	"golang.org/x/term"
+)
+
+func getUsername() (string, error) {
+	user := os.Getenv("DB_USER")
+	if user == "" {
+		var err error
+		fmt.Printf("DB Benutzer: ")
+		user, err = bufio.NewReader(os.Stdin).ReadString('\n')
+		if err != nil {
+			return fmt.Errorf("error: cmd/data/helpers.go getUsername bufio.NewReader().ReadString(): %v", err)
+		}
+	}
+	return strings.TrimSpace(user), nil
+}
+
+func getPassword() (string, error) {
+	pass := os.Getenv("DB_PASS")
+	if pass == "" {
+		fmt.Printf("DB Passwort: ")
+		bytePass, err := term.ReadPassword(int(syscall.Stdin))
+		if err != nil {
+			return fmt.Errorf("error: cmd/data/helpers.go getPassword term.ReadPassword(): %v", err)
+		}
+		fmt.Println()
+		pass = strings.TrimSpace(string(bytePass))
+	}
+	return pass, nil
+}
+
+func getCredentials() (string, string, error) {
+	user, err := getUsername()
+	if err != nil {
+		return "", "", fmt.Errorf("error: cmd/data/helpers.go getCredentials getUsername(): %v", err)
+	}
+
+	pass, err := getPassword()
+	if err != nil {
+		return "", "", fmt.Errorf("error: cmd/data/helpers.go getCredentials getPassword(): %v", err)
+	}
+
+	return user, pass, nil
+}