How can I store an array into dynamoDB table - amazon-web-services

Question

I have the following struct:
type User struct {
ID string `json:"id"`
Name string `json:"name"`
LastName string `json:"lastName"`
User string `json:"user"`
Password string `json:"password"`
Vehicles []Vehicle `json:"vehicles"`
}
type Vehicle struct {
Plate string `json:"plate"`
}
I want to store an array of Vehicles in my DynamoDB. I did some research and I found that I should use the following code:
input := &dynamodb.PutItemInput{
TableName: aws.String(tableUsers),
Item: map[string]*dynamodb.AttributeValue{
"id": {
S: aws.String(fmt.Sprintf("%v", uuid)),
},
"name": {
S: aws.String(user.Name),
},
"lastName": {
S: aws.String(user.LastName),
},
"user": {
S: aws.String(user.User),
},
"password": {
S: aws.String(user.Password),
},
"vehicles": {
L: [{
M: {
"plate": {S: aws.String("test")},
},
}],
},
},
}
But I keep having a syntax error in:
L: [{
M: {
"plate": {S: aws.String("test")},
},
}],
What am I doing wrong?

Answer 1

If you look at the dynamodb's godoc: https://docs.aws.amazon.com/sdk-for-go/api/service/dynamodb/#AttributeValue
You can see that the field L has the following type: []*AttributeValue
When you create a slice litteral you should specify its type.
So for you case it's:
L: []*dynamodb.AttributeValue{
{
M: map[string]*dynamodb.AttributeValue{
"plate": {S: aws.String("test")}
}
}
}
If you want to better understand struct, slices and map your can read the following articles:
https://blog.golang.org/go-slices-usage-and-internals
https://blog.golang.org/go-maps-in-action