In mongodb-go-driver, how to marshal/unmarshal BSON in to a struct
The official MongoDB driver uses the objectid.ObjectID type for MongoDB ObjectIds. This type is:
type ObjectID [12]byte
So you need to change your struct to:
type Language struct {
ID objectid.ObjectID `json:"id" bson:"_id"`
Name string `json:"name" bson:"name"`
Vowels []string `json:"vowels" bson:"vowels"`
Consonants []string `json:"consonants" bson:"consonants"`
}
I had success with:
m := make(map[string]Language)
cursor, e := collection.Find(context.Background(), bson.NewDocument(bson.EC.String("name", id)))
for cursor.Next(context.Background()) {
l := Language{}
err := cursor.Decode(&l)
if err != nil {
//handle err
}
m[id] = l // you need to handle this in a for loop or something... I'm assuming there is only one result per id
}
Newer "github.com/mongodb/mongo-go-driver" expects object IDs defined as
type Application struct {
ID *primitive.ObjectID `json:"ID" bson:"_id,omitempty"`
}
This serializes into JSON "ID":"5c362f3fa2533bad3b6cf6f0"
and here is how you get the ID from insert result
if oid, ok := res.InsertedID.(primitive.ObjectID); ok {
app.ID = &oid
}
Convert from string
appID := "5c362f3fa2533bad3b6cf6f0"
id, err := primitive.ObjectIDFromHex(appID)
if err != nil {
return err
}
_, err = collection.DeleteOne(nil, bson.M{"_id": id})
Convert into string
str_id := objId.Hex()
I was getting
cannot decode objectID into an array
so i changed to
ID interface{} `bson:"_id,omitempty"`
without any issues
Update: New changes were made recently, now have to change to:
import "github.com/mongodb/mongo-go-driver/bson/primitive"
type Language struct {
ID primitive.ObjectID `bson:"_id,omitempty"` // omitempty to protect against zeroed _id insertion
Name string `json:"name" bson:"name"`
Vowels []string `json:"vowels" bson:"vowels"`
Consonants []string `json:"consonants" bson:"consonants"`
}
And take the ID value:
log.Println("lang id:", objLang.ID)
...