Mongo DB result Interface to Struct Conversion in Golang

Question

I'm receiving this error when trying to convert interface{} to struct type in golang.

interface conversion: interface {} is primitive.D, not model.ClientModel. Error in line : cm := res.(model.ClientModel)

res, err := db.FindOne(collection, filter)
    if err != nil {
        fmt.Println(err)
    }
    fmt.Println(res)

    cm := res.(model.ClientModel)
    fmt.Println(cm)

What driver are you using ? FindOne returns a *SingleResult in mongo-driver v1.5+. You can keep it generic until a call to Decode. — Flint
– Flint, Commented Apr 23, 2021 at 15:55

TommyF · Accepted Answer · 2019-06-06 09:52:26Z

1

You can .Decode(&foo) the SingleResult returned from FindOne().

var cm model.ClientModel
err := db.FindOne(collection, filter).Decode(&cm)
if err != nil {
    fmt.Println(err)
}
fmt.Println(cm)

See https://godoc.org/go.mongodb.org/mongo-driver/mongo#SingleResult for details.

answered Jun 6, 2019 at 9:52

TommyF

7,1708 gold badges39 silver badges62 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Robin Kedia Over a year ago

I cannot pass model to decode function as I'm trying to make it work with generic type by passing interface. The result of decode is stored in interface which eventually i want to return outside function and convert to struct in service layer.

Collectives™ on Stack Overflow

Mongo DB result Interface to Struct Conversion in Golang

1 Answer 1

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related