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Version of AWS SDK for Go?

v1.13.16

Version of Go (go version)?

1.9.3

What issue did you see?

When I have a record with an empty list in dynamodb, and I read it with the go sdk, and call dynamodbattribute.UnmarshalMap, then empty list values are cast to nil.

Steps to reproduce

Create an record with an empty list on the CLI:

aws dynamodb put-item --table-name resources \
--item '{"id": { "S": "555" }, "foo": { "L": [] }}'

Then fetch the record and unmarshal it:

        params := &dynamodb.GetItemInput{
		Key: map[string]*dynamodb.AttributeValue{
			"id": {
				S: aws.String(id),
			},
		},
		TableName:     aws.String(myTableName),
		ConsistentRead: aws.Bool(true),
	}
	resp, err := svc.GetItem(params)
        ...
        var json map[string]interface{}
	if err := dynamodbattribute.UnmarshalMap(resp.Item, &json); err != nil {
		panic(err)
	}
        log.Printf("JSON: %s", json)

The output is:

Item: map[id:555 foo:<nil>]

But I would expect:

Item: map[id:555 foo:[]]

If you have have an runnable example, please include it.