go练习 day02

go中使用mongodb实现增删改查

连接mongodb

yaml配置

mongodb:
  uri: mongodb://localhost:27017

初始化连接

package conf

import (
	"context"
	"fmt"
	"time"

	"github.com/spf13/viper"
	"go.mongodb.org/mongo-driver/mongo"
	"go.mongodb.org/mongo-driver/mongo/options"
)

func InitMongoDB() (*mongo.Client, error){
	ctx, cancel := context.WithTimeout(context.Background(), 20*time.Second)
	defer cancel()
	client, err := mongo.Connect(ctx, options.Client().ApplyURI(viper.GetString("mongodb.uri")))
	if err != nil {
		fmt.Printf("Mongodb 连接失败: %v", err)
		return nil, err 
	}
	fmt.Println("Mongodb 连接成功")

	return client, nil
}

在初始化方法中调用

	// ===========================
	// =初始化Mongodb连接
	mdb, err := conf.InitMongoDB()
	global.MDB = mdb // 将db对象挂在到全局
	if err != nil {
		initErr = utils.AppendError(initErr, err)
	}

在DAO中挂载到BaseDao上

package dao

import (
	"king/global"

	"go.mongodb.org/mongo-driver/mongo"
	"gorm.io/gorm"
)

type BaseDao struct {
	Orm *gorm.DB
	MDB *mongo.Client
}

func NewBaseDao() BaseDao {
	return BaseDao{
		Orm: global.DB,
		MDB: global.MDB,
	}
}

新增操作：添加一条记录

func (m *RecordDao) AddRecord(iRecordAddDTO *dto.RecordAddDTO) error{
	var iRecord model.Record
	iRecordAddDTO.ConverToModel(&iRecord)

	collection := m.MDB.Database("lowcode").Collection("lowcode")
	res, err := collection.InsertOne(context.Background(), iRecord)
	if err != nil { 
		fmt.Println(err)
		return err
	}

	// 将 res.InsertedId 转换为字符串  
	if id, ok := res.InsertedID.(primitive.ObjectID); ok {  
		insertedIdString := id.Hex()  
		iRecordAddDTO.ID = insertedIdString
		fmt.Println("Inserted ID:", insertedIdString)  
	} else {  
		fmt.Println("无法将 InsertedID 转换为 primitive.ObjectID 类型")  
	}  
	// 将字符串转换回ObjecrId  primitive.ObjectIDFromHex
	// oid, err := primitive.ObjectIDFromHex("64d492bbdc2330b9e0fdfcc1")
	// filter := bson.M{"_id": oid}
	// err = collection.FindOne(context.Background(), filter).Decode(&iRecord)
	
	return err
}

查找多条数据

//opts := options.Find().SetSort(bson.M{"enrollment": -1})
filter := bson.M{"_id": "64d492bbdc2330b9e0fdfcc1"}
res, err := collection.Find(context.Background(), filter)
res.All(context.TODO(), &resRecords)

for _, result := range resRecords {
	fmt.Println(result, "-=-=====-----==1~~~~")
}

插入多条数据

type Person struct {
	name  string
	age   int
	hobby []string
}
p1 := Person{
	name: "zs",
	age: 16,
	hobby: []string{"sport", "play"}
}

p2 := Person{
	name: "ls",
	age: 20,
	hobby: []string{"write", "play"}
}
pList := []interface{}{p1, p2}
ior, err := collection.InsertMany(context.Background(), pList)

更新数据

t := bson.M{"_id": oid}
update := bson.M{"$set": bson.M{"title": "更新明细任务编号"}}

result, err := collection.UpdateOne(context.Background(), t, update)
fmt.Println(result, "result========")