mongoDB的官方golang支持库，尚处于测试阶段。
以下为示例代码分析总结，实现最基本的CRUD操作，
可供初学者学习参考和引用。
注意：源码并不能直接运行！
本文首发于个人博客MongoDB Go Driver用法小结
安装
推荐使用goland与go mod（go modules ）
官方网站：mongo-go-driver, go modules.
在需要用到的项目中任意一个包import链接，然后右键进行sync操作，便可以导入包，注意设置代理
//example
...
import (
"go.mongodb.org/mongo-driver/mongo"
"go.mongodb.org/mongo-driver/mongo/options"
)
...
初始化
在本地数据库环境下进行，所以请确保已经开启本地的数据库服务，可通过终端运行mongo命令进行判断。
var ctx = context.Background() // create a new context
var UserColl *mongo.Collection // create a new collection
type User struct { // user type for example
ID primitive.ObjectID `bson:"_id"`
Username string `bson:"username" `
Psw string `bson:"password" `
CreatedAt time.Time `bson:"created_at"`
UpdatedAt time.Time `bson:"updated_at"`
}
// connect database
func init() {
ctx, _ := context.WithTimeout(context.Background(), 10*time.Second)
client, err := mongo.Connect(ctx, options.Client().ApplyURI("mongodb://localhost:27017")) // change the URI when you need
if err != nil {
log.Fatal(err)
}
// check connection
ctx, _ = context.WithTimeout(context.Background(), 2*time.Second)
if err = client.Ping(ctx, readpref.Primary()); err != nil {
log.Fatal(err)
}
//example coll
UserColl = client.Database("[db name]").Collection("[coll name]")
}
增
单个新增
// controllers
func ExampleMongo() {
// insert one user
NewUser := User{
Username: "userA",
Psw: "123",
}
if res, err := InsertOneUser(NewUser); err != nil {
return
} else {
fmt.Println("new post created with id: %s", res.InsertedID.(primitive.ObjectID).Hex())
}
}
// models
func InsertOneUser(user User) (*mongo.InsertOneResult, error) {
res, err := UserColl.InsertOne(ctx, bson.M{
"username": user.Username,
"psw": user.Psw,
"created_at": time.Now(),
"updated_at": time.Now()})
return res, err
}
多个新增
// controllers
func ExampleMongo() {
// insert many users
NewUsers := make([]User, 1)
NewUsers = append(NewUsers, User{
Username: "userB",
Psw: "123",
}, User{
Username: "userC",
Psw: "123",
})
if res, err := InsertManyUsers(NewUsers); err != nil {
return
} else {
fmt.Printf("inserted ids: %v\n", res.InsertedIDs)
}
}
// models
func InsertManyUsers(users []User) (*mongo.InsertManyResult, error) {
res, err := UserColl.InsertMany(ctx, []interface{}{
bson.M{
"username": users[1].Username,
"psw": users[1].Psw,
"created_at": time.Now(),
"updated_at": time.Now()},
bson.M{
"username": users[2].Username,
"psw": users[2].Psw,
"created_at": time.Now(),
"updated_at": time.Now()}})
return res, err
}
删
单个删除
// controllers
func ExampleMongo() {
// delete one user
// you can design your own filter
id, err := primitive.ObjectIDFromHex("[user id]")
if err != nil {
return
}
filterDeleteOne := bson.M{"_id": id}
if res, err := DeleteOneUser(filterDeleteOne); err != nil {
return
} else {
fmt.Printf("deleted count: %d\n", res.DeletedCount)
}
}
// models
func DeleteOneUser(filter bson.M) (*mongo.DeleteResult, error) {
res, err := UserColl.DeleteOne(ctx, filter)
return res, err
}
多个删除
// controllers
func ExampleMongo() {
// delete many users
// delete documents created older than 2 days
filterDeleteMany := bson.M{"created_at": bson.M{
"$lt": time.Now().Add(-2 * 24 * time.Hour),
}}
if res, err := DeleteManyUsers(filterDeleteMany); err != nil {
return
} else {
fmt.Printf("deleted count: %d\n", res.DeletedCount)
}
}
// models
func DeleteManyUsers(filter bson.M) (*mongo.DeleteResult, error) {
res, err := UserColl.DeleteMany(ctx, filter)
return res, err
}
查
单个查找
// controllers
func ExampleMongo() {
// find one user
id, err = primitive.ObjectIDFromHex("[user id]")
if err != nil {
return
}
filterFindOne := bson.M{"_id": id}
if res, err := FindOneUser(filterFindOne); err != nil {
return
} else {
fmt.Printf("post: %+v\n", res)
}
}
// models
func FindOneUser(filter bson.M) (User, error) {
Msg := User{}
result := UserColl.FindOne(ctx, filter)
err := result.Decode(&Msg)
return Msg, err
}
多个查找
// controllers
func ExampleMongo() {
// find many user
filterFindMany := bson.M{"[key]": "[value]"}
if res, err := FindManyUsers(filterFindMany); err != nil {
return
} else {
fmt.Printf("post: %+v\n", res)
}
}
// models
func FindManyUsers(filter bson.M) ([]User, error) {
cursor, err := UserColl.Find(ctx, filter)
if err != nil {
return nil, err
}
// iterate through all documents
var res []User
for cursor.Next(ctx) {
var p User
// decode the document into given type
if err := cursor.Decode(&p); err != nil {
return nil, err
}
res = append(res, p)
}
return res, nil
}
改
单个更改
// controllers
func ExampleMongo() {
// update one user
filter := bson.M{"[key]": "[value]"}
update := bson.M{"[key]": "[value]"}
if res, err := UpdateOneUser(filter, update); err != nil {
return
} else {
fmt.Printf("modified count: %d\n", res.ModifiedCount)
}
}
// models
func UpdateOneUser(filter bson.M, update bson.M) (*mongo.UpdateResult, error) {
res, err := UserColl.UpdateOne(ctx, filter, update)
return res, err
}
多个更改
// controllers
func ExampleMongo() {
// update many users
filter := bson.M{"[key]": "[value]"}
update := bson.M{"[key]": "[value]"}
if res, err := UpdateManyUsers(filter, update); err != nil {
return
} else {
fmt.Printf("modified count: %d\n", res.ModifiedCount)
}
}
// models
func UpdateManyUsers(filter bson.M, update bson.M) (*mongo.UpdateResult, error) {
res, err := UserColl.UpdateMany(ctx, filter, update)
return res, err
}
示例源码
Github: MongoDB Go Driver
参考文档
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