feat: 添加 Dialect.Backup 用于备份数据库

core/core.go

@@ -73,7 +73,7 @@ type Dialect interface {
 	// DriverName 与当前实例关联的驱动名称
 	//
 	// 原则上驱动名和 Dialect 应该是一一对应的，但是也会有例外，比如：
-	// github.com/lib/pq 和 github.com/jackc/pgx/v4/stdlib 功能上是相同的，
+	// github.com/lib/pq 和 github.com/jackc/pgx/v5/stdlib 功能上是相同的，
 	// 仅注册的名称的不同。
 	DriverName() string
 
@@ -153,6 +153,12 @@ type Dialect interface {
 	//
 	// NOTE: query 中不能同时存在 ? 和命名参数。因为如果是命名参数，则 Exec 等的参数顺序可以是随意的。
 	Prepare(sql string) (query string, orders map[string]int, err error)
+
+	// Backup 备份数据库
+	//
+	// dsn 初始化数据库的参数，主要从其中获取数据库名称等参数；
+	// dest 备份的文件名，格式由实现者决定；
+	Backup(dsn, dest string) error
 }
 
 // ErrConstraintExists 返回约束名已经存在的错误

db.go

@@ -19,6 +19,7 @@ type DB struct {
 	tablePrefix string
 	sqlBuilder  *sqlbuilder.SQLBuilder
 	models      *model.Models
+	dsn         string
 }
 
 // NewDB 声明一个新的 [DB] 实例
@@ -44,9 +45,15 @@ func NewDB(tablePrefix, dsn string, dialect Dialect) (*DB, error) {
 		tablePrefix: tablePrefix,
 		sqlBuilder:  sqlbuilder.New(e),
 		models:      ms,
+		dsn:         dsn,
 	}, nil
 }
 
+// Backup 备份数据库至 dest
+//
+// 具体格式由各个数据库自行决定。
+func (db *DB) Backup(dest string) error { return db.Dialect().Backup(db.dsn, dest) }
+
 // New 重新指定表名前缀为 tablePrefix
 //
 // 如果要复用表模型，可以采此方法创建一个不同表名前缀的 [DB] 对表模型进行操作。
@@ -61,6 +68,7 @@ func (db *DB) New(tablePrefix string) *DB {
 		tablePrefix: tablePrefix,
 		sqlBuilder:  sqlbuilder.New(e),
 		models:      db.models,
+		dsn:         db.dsn,
 	}
 }
 

dialect/base.go

@@ -4,6 +4,12 @@
 
 package dialect
 
+import (
+	"os/exec"
+
+	"github.com/issue9/sliceutil"
+)
+
 type base struct {
 	driverName     string
 	name           string
@@ -24,3 +30,18 @@ func (b *base) Name() string { return b.name }
 func (b *base) DriverName() string { return b.driverName }
 
 func (b *base) Quotes() (byte, byte) { return b.quoteL, b.quoteR }
+
+func buildCmdArgs(k, v string) string {
+	if v == "" {
+		return ""
+	}
+	return k + "=" + v
+}
+
+func newCommand(name string, env, kv []string) *exec.Cmd {
+	env = sliceutil.Filter(env, func(i string, _ int) bool { return i != "" })
+	kv = sliceutil.Filter(kv, func(i string, _ int) bool { return i != "" })
+	cmd := exec.Command(name, kv...)
+	cmd.Env = append(cmd.Env, env...)
+	return cmd
+}

dialect/base_test.go

@@ -0,0 +1,17 @@
+// SPDX-FileCopyrightText: 2024 caixw
+//
+// SPDX-License-Identifier: MIT
+
+package dialect
+
+import (
+	"testing"
+
+	"github.com/issue9/assert/v4"
+)
+
+func TestBuildCmdArg(t *testing.T) {
+	a := assert.New(t, false)
+	a.Equal(buildCmdArgs("-p", ""), "").
+		Equal(buildCmdArgs("-p", "123"), "-p=123")
+}

dialect/mysql.go

@@ -9,10 +9,14 @@ import (
 	"database/sql/driver"
 	"errors"
 	"fmt"
+	"net"
+	"os"
 	"strconv"
 	"strings"
 	"time"
 
+	xm "github.com/go-sql-driver/mysql"
+
 	"github.com/issue9/orm/v6/core"
 	"github.com/issue9/orm/v6/sqlbuilder"
 )
@@ -307,3 +311,38 @@ func formatTime(col *core.Column, t time.Time) (string, error) {
 	}
 	return "'" + t.Format(datetimeLayouts[index]) + "'", nil
 }
+
+func (m *mysql) Backup(dsn, dest string) error {
+	conf, err := xm.ParseDSN(dsn)
+	if err != nil {
+		return err
+	}
+
+	if conf.DBName == "" {
+		panic("未指定数据库名")
+	}
+
+	h, p, err := net.SplitHostPort(conf.Addr)
+	if err != nil {
+		return err
+	}
+
+	file, err := os.Create(dest)
+	if err != nil {
+		return err
+	}
+	defer file.Close()
+
+	cmd := newCommand("mysqldump", []string{}, []string{
+		buildCmdArgs("--host", h),
+		buildCmdArgs("--port", p),
+		buildCmdArgs("--protocol", conf.Net),
+		buildCmdArgs("--user", conf.User),
+		buildCmdArgs("--password", conf.Passwd),
+		conf.DBName,
+	})
+	cmd.Stderr = os.Stderr
+	cmd.Stdout = file
+
+	return cmd.Run()
+}

dialect/mysql_test.go

@@ -5,6 +5,7 @@
 package dialect_test
 
 import (
+	"os"
 	"testing"
 
 	"github.com/issue9/assert/v4"
@@ -284,3 +285,14 @@ func TestMysql_TypesDefault(t *testing.T) {
 		testTypesDefault(t)
 	})
 }
+
+func TestMysql_Backup(t *testing.T) {
+	a := assert.New(t, false)
+	suite := test.NewSuite(a, "", test.Mysql, test.Mariadb)
+	suite.Run(func(d *test.Driver) {
+		path := "./testdata/mysql.sql"
+		d.Assertion.NotError(d.DB.Backup(path))
+		d.Assertion.FileExists(path)
+		d.Assertion.NotError(os.Remove(path))
+	})
+}

dialect/postgres.go

@@ -9,10 +9,13 @@ import (
 	"database/sql/driver"
 	"errors"
 	"fmt"
+	"os"
 	"strconv"
 	"strings"
 	"time"
 
+	"github.com/lib/pq"
+
 	"github.com/issue9/orm/v6/core"
 )
 
@@ -261,3 +264,48 @@ func (p *postgres) formatSQL(col *core.Column) (f string, err error) {
 
 	return fmt.Sprint(v), nil
 }
+
+func (p *postgres) Backup(dsn, dest string) error {
+	// http://www.postgres.cn/docs/14/app-pgdump.html
+
+	opt, err := parsePostgresDSN(dsn)
+	if err != nil {
+		return err
+	}
+
+	cmd := newCommand("pg_dump", []string{
+		buildCmdArgs("PGPASSWORD", opt["password"]),
+	}, []string{
+		buildCmdArgs("--format", "c"),
+		buildCmdArgs("--file", dest),
+		buildCmdArgs("--host", opt["host"]),
+		buildCmdArgs("--port", opt["port"]),
+		buildCmdArgs("--username", opt["user"]),
+		buildCmdArgs("--dbname", opt["dbname"]),
+		"--no-password",
+	})
+	cmd.Stderr = os.Stderr
+	cmd.Stdout = os.Stdout
+
+	return cmd.Run()
+}
+
+func parsePostgresDSN(dsn string) (opt map[string]string, err error) {
+	if strings.HasPrefix(dsn, "postgres://") || strings.HasPrefix(dsn, "postgresql://") {
+		if dsn, err = pq.ParseURL(dsn); err != nil {
+			return nil, err
+		}
+	}
+
+	items := strings.Fields(dsn)
+	opt = make(map[string]string, len(items))
+	for _, item := range items {
+		kv := strings.Split(item, "=")
+		if len(kv) != 2 {
+			panic("参数格式错误：" + item)
+		}
+		opt[kv[0]] = kv[1]
+	}
+
+	return opt, nil
+}

dialect/postgres_test.go

@@ -6,6 +6,7 @@ package dialect_test
 
 import (
 	"database/sql"
+	"os"
 	"testing"
 
 	"github.com/issue9/assert/v4"
@@ -317,3 +318,14 @@ func TestPostgres_TypesDefault(t *testing.T) {
 		testTypesDefault(t)
 	})
 }
+
+func TestPostgres_Backup(t *testing.T) {
+	a := assert.New(t, false)
+	suite := test.NewSuite(a, "", test.Postgres)
+	suite.Run(func(d *test.Driver) {
+		path := "./testdata/postgres.sql"
+		d.Assertion.NotError(d.DB.Backup(path))
+		d.Assertion.FileExists(path)
+		d.Assertion.NotError(os.Remove(path))
+	})
+}

dialect/sqlite3.go

@@ -9,7 +9,9 @@ import (
 	"database/sql/driver"
 	"errors"
 	"fmt"
+	"os"
 	"strconv"
+	"strings"
 	"time"
 
 	"github.com/issue9/orm/v6/core"
@@ -343,3 +345,16 @@ func (s *sqlite3) formatSQL(v any) (f string, err error) {
 
 	return fmt.Sprint(v), nil
 }
+
+func (s *sqlite3) Backup(dsn, dest string) error {
+	if index := strings.IndexByte(dsn, '?'); index >= 0 {
+		dsn = dsn[:index]
+	}
+
+	data,err :=os.ReadFile(dsn)
+	if err!=nil{
+		return err
+	}
+
+	return os.WriteFile(dest, data , os.ModePerm)
+}

dialect/sqlite3_test.go

@@ -5,6 +5,7 @@
 package dialect_test
 
 import (
+	"os"
 	"testing"
 
 	"github.com/issue9/assert/v4"
@@ -328,3 +329,14 @@ func TestSqlite3_TypesDefault(t *testing.T) {
 		testTypesDefault(t)
 	})
 }
+
+func TestSqlite3_Backup(t *testing.T) {
+	a := assert.New(t, false)
+	suite := test.NewSuite(a, "", test.Sqlite3)
+	suite.Run(func(d *test.Driver) {
+		path := "./testdata/sqlite3.db"
+		d.Assertion.NotError(d.DB.Backup(path))
+		d.Assertion.FileExists(path)
+		d.Assertion.NotError(os.Remove(path))
+	})
+}

dialect/testdata/.gitignore

@@ -0,0 +1,2 @@
+*.db
+*.sql

internal/test/test.go

@@ -7,9 +7,9 @@ package test
 
 import (
 	"os"
+	"slices"
 
 	"github.com/issue9/assert/v4"
-	"github.com/issue9/sliceutil"
 
 	"github.com/issue9/orm/v6"
 	"github.com/issue9/orm/v6/core"
@@ -92,16 +92,16 @@ func NewSuite(a *assert.Assertion, tablePrefix string, dialect ...core.Dialect)
 	s := &Suite{a: a}
 	a.TB().Cleanup(func() { s.close() })
 
+	fs := flags
 	for _, c := range cases {
 		name := c.dialect.Name()
 		driver := c.dialect.DriverName()
 
-		if len(dialect) > 0 && sliceutil.Count(dialect, func(i core.Dialect, _ int) bool { return i.Name() == name && i.DriverName() == driver }) <= 0 {
+		if len(dialect) > 0 && slices.IndexFunc(dialect, func(i core.Dialect) bool { return i.Name() == name && i.DriverName() == driver }) < 0 {
 			continue
 		}
 
-		fs := flags
-		if len(fs) > 0 && sliceutil.Count(fs, func(i *flagVar, _ int) bool { return i.Name == name && i.DriverName == driver }) <= 0 {
+		if len(fs) > 0 && slices.IndexFunc(fs, func(i *flagVar) bool { return i.Name == name && i.DriverName == driver }) < 0 {
 			continue
 		}