[feat] 新增 表结构操作

schema/builder.go

@@ -0,0 +1,95 @@
+package schema
+
+import (
+	"git.fsdpf.net/go/db/v2"
+)
+
+type Builder struct {
+	db     *db.Database // The database connection instance
+	schema Schema       // The schema grammar instance
+}
+
+func New(db *db.Database) *Builder {
+	return &Builder{
+		db:     db,
+		schema: GetSchemaDialect(db),
+	}
+}
+
+// 判断数据表是否存在
+func (this Builder) HasTable(table string) (bool, error) {
+	return this.schema.TableExists(table)
+}
+
+// 判断数据库列是否存在
+func (this Builder) GetColumnListing(table string) (columns []string, err error) {
+	return this.schema.GetColumnListing(table)
+}
+
+// 修改表
+func (this Builder) Table(table string, cb func(*Blueprint)) error {
+	bp := NewBlueprint(table)
+	cb(bp)
+	return this.Build(bp)
+}
+
+// 创建表
+func (this Builder) Create(table string, cb func(*Blueprint)) error {
+	bp := NewBlueprint(table)
+	bp.Create()
+	cb(bp)
+	return this.Build(bp)
+}
+
+// 修改表名
+func (this Builder) Rename(from, to string) error {
+	bp := NewBlueprint(from)
+	bp.Rename(to)
+	return this.Build(bp)
+}
+
+// 删除表
+func (this Builder) Drop(table string) error {
+	bp := NewBlueprint(table)
+	bp.Drop()
+	return this.Build(bp)
+}
+
+// 删除表, 先判断再删除
+func (this Builder) DropIfExists(table string) error {
+	bp := NewBlueprint(table)
+	bp.DropIfExists()
+	return this.Build(bp)
+}
+
+// toSql
+func (this Builder) ToSQL(bp *Blueprint) []string {
+	return bp.ToSql(this.schema)
+}
+
+// Build execute the blueprint to build / modify the table
+func (this Builder) Build(bp *Blueprint) error {
+	sqls := this.ToSQL(bp)
+
+	if len(sqls) == 0 {
+		return nil
+	}
+
+	tx, err := this.db.Begin()
+
+	if err != nil {
+		return err
+	}
+
+	err = tx.Wrap(func() error {
+		for _, sql := range sqls {
+			if _, err := tx.Exec(sql); err != nil {
+				return err
+			}
+		}
+
+		return nil
+	})
+
+	return err
+}