go任務調度10（操作mongodb）

后臺啟動mongodb服務器端：

nohup ./bin/mongod --dbpath=./data &

package main

//導入
import (
    "context"
    "fmt"
    "go.mongodb.org/mongo-driver/bson"
    "go.mongodb.org/mongo-driver/bson/primitive"
    "go.mongodb.org/mongo-driver/mongo"
    "go.mongodb.org/mongo-driver/mongo/options"
    "go.mongodb.org/mongo-driver/mongo/readpref"
    "os"
    "time"
)

type Howie struct {
    //struct里面獲取ObjectID
    HowieId    primitive.ObjectID `bson:"_id"`
    Name       string
    Pwd        string
    Age        int64
    CreateTime int64
}

func main() {
    TestMongo("mongodb://0.0.0.0:27017")
}

func TestMongo(url string) {
    var (
        err             error
        client          *mongo.Client
        collection      *mongo.Collection
        insertOneRes    *mongo.InsertOneResult
        insertManyRes   *mongo.InsertManyResult
        delRes          *mongo.DeleteResult
        updateRes       *mongo.UpdateResult
        cursor          *mongo.Cursor
        howieArray      = GetHowieArray()
        howie           Howie
        howieArrayEmpty []Howie
        size            int64
    )
    //鏈接mongo服務
    if client, err = mongo.Connect(getContext(), options.Client().ApplyURI(url)); err != nil {
        checkErr(err)
    }
    //判斷服務是否可用
    if err = client.Ping(getContext(), readpref.Primary()); err != nil {
        checkErr(err)
    }
    //選擇數據庫和集合
    collection = client.Database("testing_base").Collection("howie")

    //刪除這個集合
    collection.Drop(getContext())

    //插入一條數據
    if insertOneRes, err = collection.InsertOne(getContext(), howieArray[0]); err != nil {
        checkErr(err)
    }

    fmt.Printf("InsertOne插入的消息ID:%v\n", insertOneRes.InsertedID)
    //批量插入數據
    if insertManyRes, err = collection.InsertMany(getContext(), howieArray[1:]); err != nil {
        checkErr(err)
    }
    fmt.Printf("InsertMany插入的消息ID:%v\n", insertManyRes.InsertedIDs)
    var Dinfo = make(map[string]interface{})
    err = collection.FindOne(getContext(), bson.D{{"name", "howie_2"}, {"age", 11}}).Decode(&Dinfo)
    fmt.Println(Dinfo)
    fmt.Println("_id", Dinfo["_id"])

    //查詢單條數據
    if err = collection.FindOne(getContext(), bson.D{{"name", "howie_2"}, {"age", 11}}).Decode(&howie); err != nil {
        checkErr(err)
    }
    fmt.Printf("FindOne查詢到的數據:%v\n", howie)

    //查詢單條數據后刪除該數據
    if err = collection.FindOneAndDelete(getContext(), bson.D{{"name", "howie_3"}}).Decode(&howie); err != nil {
        checkErr(err)
    }
    fmt.Printf("FindOneAndDelete查詢到的數據:%v\n", howie)

    //查詢單條數據后修改該數據
    if err = collection.FindOneAndUpdate(getContext(), bson.D{{"name", "howie_4"}}, bson.M{"$set": bson.M{"name": "這條數據我需要修改了"}}).Decode(&howie); err != nil {
        checkErr(err)
    }
    fmt.Printf("FindOneAndUpdate查詢到的數據:%v\n", howie)

    //查詢單條數據后替換該數據(以前的數據全部清空)
    if err = collection.FindOneAndReplace(getContext(), bson.D{{"name", "howie_5"}}, bson.M{"hero": "這條數據我替換了"}).Decode(&howie); err != nil {
        checkErr(err)
    }

    fmt.Printf("FindOneAndReplace查詢到的數據:%v\n", howie)
    //一次查詢多條數據
    // 查詢createtime>=3
    // 限制取2條
    // createtime從大到小排序的數據
    if cursor, err = collection.Find(getContext(), bson.M{"createtime": bson.M{"$gte": 2}}, options.Find().SetLimit(2), options.Find().SetSort(bson.M{"createtime": -1})); err != nil {
        checkErr(err)
    }
    if err = cursor.Err(); err != nil {
        checkErr(err)
    }
    defer cursor.Close(context.Background())
    for cursor.Next(context.Background()) {
        if err = cursor.Decode(&howie); err != nil {
            checkErr(err)
        }
        howieArrayEmpty = append(howieArrayEmpty, howie)
    }
    for _, v := range howieArrayEmpty {
        fmt.Printf("Find查詢到的數據ObejectId值%s 值:%v\n", v.HowieId.Hex(), v)
    }
    //查詢集合里面有多少數據
    if size, err = collection.CountDocuments(getContext(),bson.D{}); err != nil {
        checkErr(err)
    }
    fmt.Printf("Count里面有多少條數據:%d\n", size)

    //查詢集合里面有多少數據(查詢createtime>=3的數據)
    if size, err = collection.CountDocuments(getContext(), bson.M{"createtime": bson.M{"$gte": 3}}); err != nil {
        checkErr(err)
    }
    fmt.Printf("Count里面有多少條數據:%d\n", size)

    //修改一條數據
    if updateRes, err = collection.UpdateOne(getContext(), bson.M{"name": "howie_2"}, bson.M{"$set": bson.M{"name": "我要改了他的名字"}}); err != nil {
        checkErr(err)
    }
    fmt.Printf("UpdateOne的數據:%d\n", updateRes)

    //修改多條數據
    if updateRes, err = collection.UpdateMany(getContext(), bson.M{"createtime": bson.M{"$gte": 3}}, bson.M{"$set": bson.M{"name": "我要批量改了他的名字"}}); err != nil {
        checkErr(err)
    }

    fmt.Printf("UpdateMany的數據:%d\n", updateRes)
    //刪除一條數據
    if delRes, err = collection.DeleteOne(getContext(), bson.M{"name": "howie_1"}); err != nil {
        checkErr(err)
    }
    fmt.Printf("DeleteOne刪除了多少條數據:%d\n", delRes.DeletedCount)

    //刪除多條數據
    if delRes, err = collection.DeleteMany(getContext(), bson.M{"createtime": bson.M{"$gte": 7}}); err != nil {
        checkErr(err)
    }
    fmt.Printf("DeleteMany刪除了多少條數據:%d\n", delRes.DeletedCount)

}

func checkErr(err error) {
    if err != nil {
        if err == mongo.ErrNoDocuments {
            fmt.Println("沒有查到數據")
            os.Exit(0)
        } else {
            fmt.Println(err)
            os.Exit(0)
        }

    }
}

func getContext() (ctx context.Context) {
    ctx, _ = context.WithTimeout(context.Background(), 10*time.Second)
    return
}

func GetHowieArray() (data []interface{}) {
    var i int64
    for i = 0; i <= 10; i++ {
        data = append(data, Howie{
            HowieId:    primitive.NewObjectID(),
            Name:       fmt.Sprintf("howie_%d", i+1),
            Pwd:        fmt.Sprintf("pwd_%d", i+1),
            Age:        i + 10,
            CreateTime: i + 1,
        })
    }
    return
}

注意：從github.com/mongodb/mongo-go-driver下載下來要放到go.mongodb.org目錄對應的位置，不然會報錯