github.com/insionng/yougam@v0.0.0-20170714101924-2bc18d833463/libraries/pingcap/tidb/sessionctx/autocommit/autocommit.go (about)

     1  // Copyright 2015 PingCAP, Inc.
     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  // See the License for the specific language governing permissions and
    12  // limitations under the License.
    13  
    14  package autocommit
    15  
    16  import (
    17  	"github.com/insionng/yougam/libraries/pingcap/tidb/context"
    18  )
    19  
    20  // Checker is the interface checks if it should autocommit in the context.
    21  // TODO: Choose a better name.
    22  type Checker interface {
    23  	// ShouldAutocommit returns true if it should autocommit in the context.
    24  	ShouldAutocommit(ctx context.Context) bool
    25  }
    26  
    27  // keyType is a dummy type to avoid naming collision in context.
    28  type keyType int
    29  
    30  // String defines a Stringer function for debugging and pretty printing.
    31  func (k keyType) String() string {
    32  	return "autocommit_checker"
    33  }
    34  
    35  const key keyType = 0
    36  
    37  // BindAutocommitChecker binds autocommit checker to context.
    38  func BindAutocommitChecker(ctx context.Context, checker Checker) {
    39  	ctx.SetValue(key, checker)
    40  }
    41  
    42  // ShouldAutocommit gets checker from ctx and checks if it should autocommit.
    43  func ShouldAutocommit(ctx context.Context) bool {
    44  	v, ok := ctx.Value(key).(Checker)
    45  	if !ok {
    46  		panic("Miss autocommit checker")
    47  	}
    48  	return v.ShouldAutocommit(ctx)
    49  }