github.com/ecodeclub/eorm@v0.0.2-0.20231001112437-dae71da914d0/internal/datasource/transaction/types.go (about)

     1  // Copyright 2021 ecodeclub
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  // http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package transaction
    16  
    17  import (
    18  	"context"
    19  	"database/sql"
    20  
    21  	"github.com/ecodeclub/eorm/internal/errs"
    22  
    23  	"github.com/ecodeclub/eorm/internal/datasource"
    24  )
    25  
    26  // 为了方便管理不同类型的 分布式 Tx，所以这里引入 TxType 常量来支持创建不同的 分布式Tx类型 以便提高后续引入 XA 方案的扩展性。
    27  const (
    28  	Delay  = "delay"
    29  	Single = "single"
    30  )
    31  
    32  type TxFactory interface {
    33  	TxOf(ctx Context, finder datasource.Finder) (datasource.Tx, error)
    34  }
    35  
    36  type Context struct {
    37  	TxName string
    38  	TxCtx  context.Context
    39  	Opts   *sql.TxOptions
    40  }
    41  
    42  type TypeKey struct{}
    43  
    44  func UsingTxType(ctx context.Context, val string) context.Context {
    45  	return context.WithValue(ctx, TypeKey{}, val)
    46  }
    47  
    48  func GetCtxTypeKey(ctx context.Context) any {
    49  	return ctx.Value(TypeKey{})
    50  }
    51  
    52  type TxFacade struct {
    53  	factory TxFactory
    54  	finder  datasource.Finder
    55  }
    56  
    57  func NewTxFacade(ctx context.Context, finder datasource.Finder) (TxFacade, error) {
    58  	res := TxFacade{
    59  		finder: finder,
    60  	}
    61  	switch GetCtxTypeKey(ctx).(string) {
    62  	case Delay:
    63  		res.factory = DelayTxFactory{}
    64  		return res, nil
    65  	case Single:
    66  		res.factory = SingleTxFactory{}
    67  		return res, nil
    68  	default:
    69  		return TxFacade{}, errs.ErrUnsupportedDistributedTransaction
    70  	}
    71  }
    72  
    73  func (t *TxFacade) BeginTx(ctx context.Context, opts *sql.TxOptions) (datasource.Tx, error) {
    74  	dsCtx := Context{
    75  		TxCtx:  ctx,
    76  		Opts:   opts,
    77  		TxName: GetCtxTypeKey(ctx).(string),
    78  	}
    79  	return t.factory.TxOf(dsCtx, t.finder)
    80  }