Upsert not working when using UpdateOne with the MongoDB Golang driver

Question

For reference, I have this struct:

type OpenOrderCleaned struct {
    OrderID             string    `json:"orderId" bson:"orderId"`
    DateTimeOrderPlaced time.Time `json:"dateTimeOrderPlaced" bson:"dateTimeOrderPlaced"`
    OrderItems          []struct {
        OrderItemID   string `json:"orderItemId" bson:"orderItemId"`
        Ean           string `json:"ean" bson:"ean"`
        CancelRequest bool   `json:"cancelRequest" bson:"cancelRequest"`
        Quantity      int    `json:"quantity" bson:"quantity"`
    } `json:"orderItems" bson:"orderItems"`
}

I get an API response with multiple JSON instances that I want to save in MongoDB, so I use a for loop. I want to check if a document already exists in the database, by using the orderId field, which is unique for every JSON instance. I thought UpdateOne was a good option for this because it has upsert. So if the orderId does not exist, the full document should be generated and stored in the database.

for _, OpenOrderCleaned := range o.Orders {

    c := auth.GetClient()
    collection := c.Database("goprac").Collection(x)

    filter := bson.M{"orderId": bson.M{"$eq": OpenOrderCleaned.OrderID}}
    update := bson.M{
        "$set": bson.M{
            "orderId":             OpenOrderCleaned.OrderID,
            "dateTimeOrderPlaced": OpenOrderCleaned.DateTimeOrderPlaced,
            "orderItems":          OpenOrderCleaned.OrderItems,
        },
    }

    ctx, _ := context.WithTimeout(context.Background(), 15*time.Second)
    result, err := collection.UpdateOne(ctx, filter, update)

    if err != nil {
        fmt.Println("UpdateOne() result ERROR:", err)
        os.Exit(1)
    } else {
        fmt.Println("UpdateOne() result:", result)
        fmt.Println("UpdateOne() result TYPE:", reflect.TypeOf(result))
        fmt.Println("UpdateOne() result MatchedCount:", result.MatchedCount)
        fmt.Println("UpdateOne() result ModifiedCount:", result.ModifiedCount)
        fmt.Println("UpdateOne() result UpsertedCount:", result.UpsertedCount)
        fmt.Println("UpdateOne() result UpsertedID:", result.UpsertedID)
    }

}

But right now the Upsert is not working. When I put a manual document into MongoDB and running the program, it is updating though. So why are new instances not made in the database? Do I have to state somewhere upsert=True or something? Or is maybe the mapping of "orderItems": OpenOrderCleaned.OrderItems not correct?

Any help is appreciated.

Answer 1

You are calling update, not upsert. You have to pass the correct options to UpdateOne to upsert. This is from the mongo driver examples:

opts := options.Update().SetUpsert(true)
filter := bson.D{{"_id", id}}
update := bson.D{{"$set", bson.D{{"email", "[email protected]"}}}}

result, err := coll.UpdateOne(context.TODO(), filter, update, opts)

You are missing the opts.