无法从Mongo记录[mgo]：golang在结构接口上仅向上插入一个值

Question

Basically I want update in one value from the mongodb document by given fully struct interface as a change parameter in collection.Upsert(selector,change). how we do this without lose other values into empty. Other(type,category.rerportby,createon,info) values should be keep on existing values only update plant and location values into PLANT07 and BAR)

NOTE: I want use completely Service Notification Struct Object for do this.

DatabaseName:WO 
CollectionName:SERVICE_NOTIFICATIONS

package models

//models.ServiceNotification
type ServiceNotification struct {
    NotificationNo string                `json:"notification_no" bson:"notification_no"`
    Type           string                `json:"type" bson:"type"`
    Category       string                `json:"category" bson:"category"`
        Plant          string                `json:"plant" bson:"plant"`
    Location         string              `json:"location" bson:"location"`
    ReportedBy     string                `json:"reportedby" bson:"reportedby"`
    Info           map[string]interface{}`json:"info" bson:"info"`
    SAPInfo        SAPNotificationInfo   `json:"sapinfo" bson:"sapinfo"`
        CreateOn       string                `json:"createon" bson:"createon"`
    UpdateOn       string                `json:"updateon" bson:"updateon"`
}

package main

func main(){

input := models.ServiceNotification{
    NotificationNo:000120,
    Plant:"Plant07",
    Location:"BAR",
}
Change_ServiceNotification(input)

}

I want update plant and location by given complete struct interface to the mongo Upsert function. because I want to decide dynamically what should update . But when I update plant and location other values going to be LOST. in mongo record.

func Change_ServiceNotification(notification models.ServiceNotification) error {
    session, err := commons.GetMongoSession()
    if err != nil {
        return errors.New("Cannot create mongodb session" + err.Error())
    }
    defer session.Close()
    var col = session.DB(WO).C(SERVICE_NOTIFICATIONS)

    selector := bson.M{"notification_no": notification.NotificationNo}

    _, err = col.Upsert(selector, notification)
    if err != nil {
        errMsg := "Cannot update service notification " + err.Error()
        return errors.New(errMsg)
    }
    return nil
}

Appreciate your help

Thanks in advance

Answer 1

You cannot do it this way, but you can use the $set operator of MongoDB (Skipping error checking):

input := Bson.M{
    "$set": bson.M{
        "plant": "Plant07",
        // Further fields here...
    }
}
selector := bson.M{"notification_no": notification.NotificationNo}
col.Upsert(selector, input)

This will update only the provided fields.