51工具盒子

依楼听风雨
笑看云卷云舒,淡观潮起潮落
当前位置：工具盒子 > 软件使用 > 正文

如何在Go中以UUID类型保存Mongo中的数据？

2024-12-01 分类：软件使用 阅读(9) 评论(0)

英文:

How to save something in Mongo in UUID type by Go?

问题 {#heading}

通过MongoDB控制台，我可以添加文档：

{
    "_id": ObjectID(),
    "name": "John",
    "sign": UUID("32e79135-76c4-4682-80b2-8c813be9b792")
}

然后，我可以读取它：

{
    _id: ObjectId('64d4ce25ac7c4327e76a53e3'),
    name: "John",
    sign: UUID("32e7913576c4468280b28c813be9b792")
}

我可以执行：

db.getCollection('people').find({"sign": UUID("32e79135-76c4-4682-80b2-8c813be9b792")})

然后，我可以找到这个人。

但是，当我尝试在Go中执行时：

package main

import (
    "context"
    "fmt"
    "log"

    "github.com/google/uuid"
    "go.mongodb.org/mongo-driver/mongo"
    "go.mongodb.org/mongo-driver/mongo/options"
)

type Person struct {
    Name string    `bson:"name"`
    Sign uuid.UUID `bson:"sign"`
}

func main() {
    client, err := mongo.Connect(context.Background(), options.Client().ApplyURI("mongodb://localhost:27017"))
    if err != nil {
        log.Fatal(err)
    }
    defer client.Disconnect(context.Background())

    db := client.Database("mydatabase")
    collection := db.Collection("people")

    signUUID := uuid.New()

    person := Person{
        Name: "John",
        Sign: signUUID,
    }

    _, err = collection.InsertOne(context.Background(), person)
    if err != nil {
        log.Fatal(err)
    }

    fmt.Println("Document inserted successfully")
}

然后，在MongoDB中，我有：

{
    _id: ObjectId('64d4cf0a308251580cffee4e'),
    name: 'John',
    sign: BinData(0, 'wqaX6oYLT1eurEEhIciK9Q==')
}

我希望拥有一个UUID类型的"sign"字段，并能够在MongoDB中轻松地按其搜索。 英文:

By MongoDB console I can add document:

{
        "_id": ObjectID(),
        "name": "John",
        "sign": UUID("32e79135-76c4-4682-80b2-8c813be9b792")
}

And next I can read it:

{
    _id: ObjectId('64d4ce25ac7c4327e76a53e3'),
    name: "John",
    sign: UUID("32e7913576c4468280b28c813be9b792")
}

I can do:

db.getCollection('people').find({"sign": UUID("32e79135-76c4-4682-80b2-8c813be9b792")})

And I can find the people.

But when I try it in Go:

package main

import (
\"context\"
\"fmt\"
\"log\"


    "github.com/google/uuid"
    "go.mongodb.org/mongo-driver/mongo"
    "go.mongodb.org/mongo-driver/mongo/options"




)


type Person struct {
Name string    `bson:"name"`
Sign uuid.UUID `bson:"sign"`
}


func main() {
client, err := mongo.Connect(context.Background(), options.Client().ApplyURI(\"mongodb://localhost:27017\"))
if err != nil {
log.Fatal(err)
}
defer client.Disconnect(context.Background())


    db := client.Database("mydatabase")
    collection := db.Collection("people")

    signUUID := uuid.New()

    person := Person{
    	Name: "John",
    	Sign: signUUID,
    }

    _, err = collection.InsertOne(context.Background(), person)
    if err != nil {
    	log.Fatal(err)
    }

    fmt.Println("Document inserted successfully")




}

Then in Mongo I have:

{
_id: ObjectId('64d4cf0a308251580cffee4e'),
name: 'John',
sign: BinData(0, 'wqaX6oYLT1eurEEhIciK9Q==')
}

I would like to have a "sign" field of type UUID and be able to easily search by it in Mongo.

答案1 {#1}

得分: 2

The package github.com/google/uuid 不实现 bson.ValueMarshaler 接口来将自身编组为 mongodb UUID，因此它无法正常工作。

我们可以注册我们自己的编解码器来对其进行编码或解码以转换为或从 mongodb UUID。请参见以下演示：

package main

import (
	"context"
	"fmt"
	"log"
	"reflect"

	"github.com/google/uuid"
	"go.mongodb.org/mongo-driver/bson"
	"go.mongodb.org/mongo-driver/bson/bsoncodec"
	"go.mongodb.org/mongo-driver/bson/bsonrw"
	"go.mongodb.org/mongo-driver/mongo"
	"go.mongodb.org/mongo-driver/mongo/options"
)

type Person struct {
	Name string    `bson:"name"`
	Sign uuid.UUID `bson:"sign"`
}

func main() {
	tUUID := reflect.TypeOf(uuid.Nil)
	bson.DefaultRegistry.RegisterTypeEncoder(tUUID, bsoncodec.ValueEncoderFunc(func(ec bsoncodec.EncodeContext, vw bsonrw.ValueWriter, val reflect.Value) error {
		// borrowed from https://github.com/mongodb/mongo-go-driver/blob/89c7e1d1d9a2954472fe852baf27ecca9dbf9bbf/bson/bsoncodec/default_value_encoders.go#L684-L691
		if !val.IsValid() || val.Type() != tUUID {
			return bsoncodec.ValueEncoderError{Name: "UUIDEncodeValue", Types: []reflect.Type{tUUID}, Received: val}
		}
		uuid := val.Interface().(uuid.UUID)

		return vw.WriteBinaryWithSubtype(uuid[:], bson.TypeBinaryUUID)
	}))
	bson.DefaultRegistry.RegisterTypeDecoder(tUUID, bsoncodec.ValueDecoderFunc(func(dc bsoncodec.DecodeContext, vr bsonrw.ValueReader, val reflect.Value) error {
		// borrowed from https://github.com/mongodb/mongo-go-driver/blob/89c7e1d1d9a2954472fe852baf27ecca9dbf9bbf/bson/bsoncodec/default_value_decoders.go#L694-L706
		if !val.CanSet() || val.Type() != tUUID {
			return bsoncodec.ValueDecoderError{Name: "UUIDDecodeValue", Types: []reflect.Type{tUUID}, Received: val}
		}

		var data []byte
		var subtype byte
		var err error
		switch vrType := vr.Type(); vrType {
		case bson.TypeBinary:
			data, subtype, err = vr.ReadBinary()
		case bson.TypeNull:
			err = vr.ReadNull()
		case bson.TypeUndefined:
			err = vr.ReadUndefined()
		default:
			err = fmt.Errorf("cannot decode %v into a Binary", vrType)
		}

		if err != nil {
			return err
		}

		if subtype != bson.TypeBinaryUUID {
			return fmt.Errorf("cannot decode subtype %v into a UUID", subtype)
		}

		val.Set(reflect.ValueOf(uuid.UUID(data)))
		return nil
	}))

	client, err := mongo.Connect(context.Background(), options.Client().ApplyURI("mongodb://localhost:27017"))
	if err != nil {
		log.Fatal(err)
	}
	defer client.Disconnect(context.Background())

	db := client.Database("mydatabase")
	collection := db.Collection("people")

	signUUID := uuid.New()

	person := Person{
		Name: "John",
		Sign: signUUID,
	}

	if _, err = collection.InsertOne(context.Background(), person); err != nil {
		log.Fatal(err)
	}

	var p Person

	if err := collection.FindOne(context.Background(),
		bson.M{"sign": signUUID},
	).Decode(&p); err != nil {
		log.Fatal(err)
	}
	log.Printf("%+v\n", p)
}

请参阅此处的讨论：Add support for mongodb UUID type。

为了完整起见，以下显示了实现 bson.ValueMarshaler 和 bson.ValueUnmarshaler 接口的方法：

package main

import (
	"context"
	"errors"
	"fmt"
	"log"

	"github.com/google/uuid"
	"go.mongodb.org/mongo-driver/bson"
	"go.mongodb.org/mongo-driver/bson/bsontype"
	"go.mongodb.org/mongo-driver/mongo"
	"go.mongodb.org/mongo-driver/mongo/options"
	"go.mongodb.org/mongo-driver/x/bsonx/bsoncore"
)

type myUUID struct {
	uuid.UUID
}

var (
	_ bson.ValueMarshaler   = (*myUUID)(nil)
	_ bson.ValueUnmarshaler = (*myUUID)(nil)
)

func (u myUUID) MarshalBSONValue() (bsontype.Type, []byte, error) {
	return bson.TypeBinary, bsoncore.AppendBinary(nil, bson.TypeBinaryUUID, []byte(u.UUID[:])), nil
}

func (u *myUUID) UnmarshalBSONValue(typ bsontype.Type, value []byte) error {
	if typ != bson.TypeBinary {
		return fmt.Errorf("cannot unmarshal %v into a Binary", typ)
	}
	subtype, bin, rem, ok := bsoncore.ReadBinary(value)
	if subtype != bson.TypeBinaryUUID {
		return fmt.Errorf("cannot unmarshal binary subtype %v into a UUID", subtype)
	}
	if len(rem) > 0 {
		return fmt.Errorf("value has extra data: %v", rem)
	}
	if !ok {
		return errors.New("value does not have enough bytes")
	}
	*u = myUUID{UUID: uuid.UUID(bin)}
	return nil
}

type Person struct {
	Name string `bson:"name"`
	Sign myUUID `bson:"sign"`
}

func main() {
	client, err := mongo.Connect(context.Background(), options.Client().ApplyURI("mongodb://localhost:27017"))
	if err != nil {
		log.Fatal(err)
	}
	defer client.Disconnect(context.Background())

	db := client.Database("mydatabase")
	collection := db.Collection("people")

	signUUID := myUUID{UUID: uuid.New()}

	person := Person{
		Name: "John",
		Sign: signUUID,
	}

	if _, err = collection.InsertOne(context.Background(), person); err != nil {
		log.Fatal(err)
	}

	var p Person

	if err := collection.FindOne(context.Background(),
		bson.M{"sign": signUUID},
	).Decode(&p); err != nil {
		log.Fatal(err)
	}
	log.Printf("%+v\n", p)
}

英文:

The package github.com/google/uuid does not implement the bson.ValueMarshaler interface to marshal itself into a mongodb UUID, that's why it does not work.

We can register our own codec to encode it to or decode it from mongodb UUID. See the demo below:

package main

import (
	"context"
	"fmt"
	"log"
	"reflect"

	"github.com/google/uuid"
	"go.mongodb.org/mongo-driver/bson"
	"go.mongodb.org/mongo-driver/bson/bsoncodec"
	"go.mongodb.org/mongo-driver/bson/bsonrw"
	"go.mongodb.org/mongo-driver/mongo"
	"go.mongodb.org/mongo-driver/mongo/options"
)

type Person struct {
	Name string    `bson:"name"`
	Sign uuid.UUID `bson:"sign"`
}

func main() {
	tUUID := reflect.TypeOf(uuid.Nil)
	bson.DefaultRegistry.RegisterTypeEncoder(tUUID, bsoncodec.ValueEncoderFunc(func(ec bsoncodec.EncodeContext, vw bsonrw.ValueWriter, val reflect.Value) error {
		// borrowed from https://github.com/mongodb/mongo-go-driver/blob/89c7e1d1d9a2954472fe852baf27ecca9dbf9bbf/bson/bsoncodec/default_value_encoders.go#L684-L691
		if !val.IsValid() || val.Type() != tUUID {
			return bsoncodec.ValueEncoderError{Name: "UUIDEncodeValue", Types: []reflect.Type{tUUID}, Received: val}
		}
		uuid := val.Interface().(uuid.UUID)

		return vw.WriteBinaryWithSubtype(uuid[:], bson.TypeBinaryUUID)
	}))
	bson.DefaultRegistry.RegisterTypeDecoder(tUUID, bsoncodec.ValueDecoderFunc(func(dc bsoncodec.DecodeContext, vr bsonrw.ValueReader, val reflect.Value) error {
		// borrowed from https://github.com/mongodb/mongo-go-driver/blob/89c7e1d1d9a2954472fe852baf27ecca9dbf9bbf/bson/bsoncodec/default_value_decoders.go#L694-L706
		if !val.CanSet() || val.Type() != tUUID {
			return bsoncodec.ValueDecoderError{Name: "UUIDDecodeValue", Types: []reflect.Type{tUUID}, Received: val}
		}

		var data []byte
		var subtype byte
		var err error
		switch vrType := vr.Type(); vrType {
		case bson.TypeBinary:
			data, subtype, err = vr.ReadBinary()
		case bson.TypeNull:
			err = vr.ReadNull()
		case bson.TypeUndefined:
			err = vr.ReadUndefined()
		default:
			err = fmt.Errorf("cannot decode %v into a Binary", vrType)
		}

		if err != nil {
			return err
		}

		if subtype != bson.TypeBinaryUUID {
			return fmt.Errorf("cannot decode subtype %v into a UUID", subtype)
		}

		val.Set(reflect.ValueOf(uuid.UUID(data)))
		return nil
	}))

	client, err := mongo.Connect(context.Background(), options.Client().ApplyURI("mongodb://localhost:27017"))
	if err != nil {
		log.Fatal(err)
	}
	defer client.Disconnect(context.Background())

	db := client.Database("mydatabase")
	collection := db.Collection("people")

	signUUID := uuid.New()

	person := Person{
		Name: "John",
		Sign: signUUID,
	}

	if _, err = collection.InsertOne(context.Background(), person); err != nil {
		log.Fatal(err)
	}

	var p Person

	if err := collection.FindOne(context.Background(),
		bson.M{"sign": signUUID},
	).Decode(&p); err != nil {
		log.Fatal(err)
	}
	log.Printf("%+v\n", p)
}

See the discussion here: Add support for mongodb UUID type.

For the sake of completeness, below shows the approach that implements the bson.ValueMarshaler and bson.ValueUnmarshaler interfaces:

package main

import (
	"context"
	"errors"
	"fmt"
	"log"

	"github.com/google/uuid"
	"go.mongodb.org/mongo-driver/bson"
	"go.mongodb.org/mongo-driver/bson/bsontype"
	"go.mongodb.org/mongo-driver/mongo"
	"go.mongodb.org/mongo-driver/mongo/options"
	"go.mongodb.org/mongo-driver/x/bsonx/bsoncore"
)

type myUUID struct {
	uuid.UUID
}

var (
	_ bson.ValueMarshaler   = (*myUUID)(nil)
	_ bson.ValueUnmarshaler = (*myUUID)(nil)
)

func (u myUUID) MarshalBSONValue() (bsontype.Type, []byte, error) {
	return bson.TypeBinary, bsoncore.AppendBinary(nil, bson.TypeBinaryUUID, []byte(u.UUID[:])), nil
}

func (u *myUUID) UnmarshalBSONValue(typ bsontype.Type, value []byte) error {
	if typ != bson.TypeBinary {
		return fmt.Errorf("cannot unmarshal %v into a Binary", typ)
	}
	subtype, bin, rem, ok := bsoncore.ReadBinary(value)
	if subtype != bson.TypeBinaryUUID {
		return fmt.Errorf("cannot unmarshal binary subtype %v into a UUID", subtype)
	}
	if len(rem) > 0 {
		return fmt.Errorf("value has extra data: %v", rem)
	}
	if !ok {
		return errors.New("value does not have enough bytes")
	}
	*u = myUUID{UUID: uuid.UUID(bin)}
	return nil
}

type Person struct {
	Name string `bson:"name"`
	Sign myUUID `bson:"sign"`
}

func main() {
	client, err := mongo.Connect(context.Background(), options.Client().ApplyURI("mongodb://localhost:27017"))
	if err != nil {
		log.Fatal(err)
	}
	defer client.Disconnect(context.Background())

	db := client.Database("mydatabase")
	collection := db.Collection("people")

	signUUID := myUUID{UUID: uuid.New()}

	person := Person{
		Name: "John",
		Sign: signUUID,
	}

	if _, err = collection.InsertOne(context.Background(), person); err != nil {
		log.Fatal(err)
	}

	var p Person

	if err := collection.FindOne(context.Background(),
		bson.M{"sign": signUUID},
	).Decode(&p); err != nil {
		log.Fatal(err)
	}
	log.Printf("%+v\n", p)
}

赞(1)
未经允许不得转载：工具盒子 » 如何在Go中以UUID类型保存Mongo中的数据？
标签：

厉飞雨

众生皆苦，唯有自渡！

相关推荐

最新文章

猜你喜欢

快捷分类

云服务器 日常运维 在线免费 开源工具 科学上网 开发笔记 区块链 白嫖帮 新视野 人工智能 网赚思路 Python笔记 Php笔记 Java笔记 链知识 币知识 IOS笔记 Android笔记 Mysql C语言笔记 前端开发 R笔记 Go笔记 mybatis笔记 Golang笔记 数据库 市场营销 软件教程 vps Rust笔记 软件使用 经验分享 Stable Diffusion chatgpt Midjourney 操作系统 Photoscape 加密货币 挖矿 Coze Meta 网络安全 网络运营 开源软件 Github ComfyUI 数字人 Docker笔记 Claude Oracle web3 linux windows mac redis git笔记 nginx kafka maven spring RocketMQ Zabbix ubuntu centos kubesphere ffmpeg jenkins hbase JavaScript笔记 WordPress nginx Hadoop vuejs mongo SQL Server PostgreSQL SQLite ElasticSearch Spark netty zookeeper RabbitMQ ClickHoust cocos2d gradle tomcat Markdown MinIO react Hexo git intellij idea android studio svn C++ spdlog nodejs C WordPress 宝塔面板 vim shell logstash 软件渗透 NeoDB CSS3 HTML Lua笔记 数据算法 嵌入式 debian 红帽RHEL Neo4j jquery