github.com/ecodeclub/eorm@v0.0.2-0.20231001112437-dae71da914d0/internal/valuer/primitive.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 valuer
    16  
    17  import (
    18  	"database/sql"
    19  	"reflect"
    20  
    21  	"github.com/ecodeclub/eorm/internal/rows"
    22  
    23  	"github.com/ecodeclub/eorm/internal/model"
    24  )
    25  
    26  // primitiveValue 支持基本类型 Value
    27  type primitiveValue struct {
    28  	Value
    29  	val     any
    30  	valType reflect.Type
    31  }
    32  
    33  // Field 返回字段值
    34  func (s primitiveValue) Field(name string) (reflect.Value, error) {
    35  	return s.Value.Field(name)
    36  }
    37  
    38  // SetColumns 设置列值， 支持基本类型，基于 reflect 与 unsafe Value 封装
    39  func (s primitiveValue) SetColumns(rows rows.Rows) error {
    40  	switch s.valType.Elem().Kind() {
    41  	case reflect.Struct:
    42  		if scanner, ok := s.val.(sql.Scanner); ok {
    43  			return rows.Scan(scanner)
    44  		}
    45  		return s.Value.SetColumns(rows)
    46  	default:
    47  		return rows.Scan(s.val)
    48  	}
    49  }
    50  
    51  // PrimitiveCreator 支持基本类型的 Creator, 基于原生的 Creator 扩展
    52  type PrimitiveCreator struct {
    53  	Creator
    54  }
    55  
    56  // NewPrimitiveValue 返回一个封装好的，基于支持基本类型实现的 Value
    57  // 输入 val 必须是一个指向结构体实例的指针，而不能是任何其它类型
    58  func (c PrimitiveCreator) NewPrimitiveValue(val any, meta *model.TableMeta) Value {
    59  	return primitiveValue{
    60  		val:     val,
    61  		Value:   c.Creator(val, meta),
    62  		valType: reflect.TypeOf(val),
    63  	}
    64  }