我如何对AWS-SDK-GO-V2 DYNAMODB实现进行单元测试

Question

I am still grasping go-interfaces and I can mock the WaitUntilTableExists func. But unable to mock PutItemRequest.

Here's my main.go snippet

func MyPutItem(d mydata, client dynamodbiface.DynamoDBAPI) error {
    input := &dynamodb.PutItemInput{
        ....
    }
    req := client.PutItemRequest(input)
    result, err := req.Send()
    log.Println(result)
    return err
}

main_test.go snippet

type mockDynamoDBClient struct {
    dynamodbiface.DynamoDBAPI
}

func (m *mockDynamoDBClient) PutItemRequest(input *dynamodb.PutItemInput) dynamodb.PutItemRequest {
    // Most probably this is where I need your help
}

func TestStoreInDynamoDB(t *testing.T) {
    var mockClient = new(mockDynamoDBClient)
    d := mydata{}
    result := DynampDBPutItem(d, mockClient)
    t.Log(result)
}

Answer 1

Faking the SDK like this works:

main_test.go

type fakeDynamoDBClient struct {
    dynamodbiface.DynamoDBAPI
}

func (m *fakeDynamoDBClient) GetItemRequest(input *dynamodb.GetItemInput) dynamodb.GetItemRequest {
    return dynamodb.GetItemRequest{
        Request: &aws.Request{
            Data: &dynamodb.GetItemOutput{
                Item: map[string]dynamodb.AttributeValue{
                    "count": dynamodb.AttributeValue{
                        N: aws.String("10"),
                    },
                },
            },
        },
    }
}

func (m *fakeDynamoDBClient) PutItemRequest(input *dynamodb.PutItemInput) dynamodb.PutItemRequest {
    return dynamodb.PutItemRequest{
        Request: &aws.Request{
            Data: &dynamodb.PutItemOutput{},
        },
    }
}

func TestUpdateCount(t *testing.T) {
    err := UpdateCount(10, &fakeDynamoDBClient{})
    if err != nil {
        t.Error("Failed to update badge count on dynamodb", err)
    }
}

main.go

func UpdateCount(count int, client dynamodbiface.DynamoDBAPI) error {
    ...
}