Example

You can instantiate *dynamodb.DynamoDB and pass that as a parameter to all methods connecting to DynamoDB, or as unitTest demonstrates, create your own type and pass it along as a field.

Test-compatible DynamoDB field

If you use *dynamodb.DynamoDB as a field, you will be unable to unit test it, as documented in #88. Cast it instead as dynamodbiface.DynamoDBAPI:

type ItemGetter struct {
		DynamoDB dynamodbiface.DynamoDBAPI
}

Querying actual DynamoDB

You'll need an *aws.Config and *session.Session for these to work correctly:

// Setup
var getter = new(ItemGetter)
var config *aws.Config = &aws.Config{Region: aws.String("us-west-2"),}
var sess *session.Session = session.NewSession(config)
var svc *dynamodb.DynamoDB = dynamodb.New()
getter.DynamoDB = dynamodbiface.DynamoDBAPI(svc)
// Finally
getter.DynamoDB.GetItem(/* ... */)

Querying in tests

Construct a fakeDynamoDB and add the necessary methods for each of those structs (custom ones for ItemGetter and whatever methods you're using for DynamoDB), and you're good to go!

type fakeDynamoDB struct {
		dynamodbiface.DynamoDBAPI
}
var getter = new(ItemGetter)
getter.DynamoDB = &fakeDynamoDB{}
// And to run it (assuming you've mocked fakeDynamoDB.GetItem)
getter.DynamoDB.GetItem(/* ... */)

Output

$ go test -tags example -cover
PASS
coverage: 100.0% of statements
ok		_/Users/shatil/workspace/aws-sdk-go/example/service/dynamodb/unitTest	0.008s