cloudformation_test.go

package awsutil_test

import (
	"fmt"
	"testing"

	"log"

	"github.com/aws/aws-sdk-go/service/cloudformation"
	"github.com/aws/aws-sdk-go/service/ec2"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/mock"
	"github.com/tleyden/aws-sdk-mock/mockcloudformation"
	"github.com/tleyden/aws-sdk-mock/mockec2"
	"github.com/tleyden/awsutil"
	"github.com/aws/aws-sdk-go/aws"
)

func TestStopEC2Instances(t *testing.T) {

	mockInstanceId := "i-mock"

	cfnUtil, mockCfn, mockEc2 := NewMockCloudformationUtil()

	// Mock cloudformation returns stack with some ec2 instances and some non-ec2 instances
	mockCfn.On("DescribeStackResources", mock.Anything).Return(
		&cloudformation.DescribeStackResourcesOutput{
			StackResources: []*cloudformation.StackResource{
				{
					ResourceType:       awsutil.StringPointer(awsutil.AWS_EC2_INSTANCE),
					PhysicalResourceId: &mockInstanceId,
				},
				{
					ResourceType: awsutil.StringPointer(awsutil.AWS_EC2_HOST),
				},
			},
		},
		nil,
	).Once()

	// The mock ec2 API is expecting to get this as the parameter to
	// the ec2Api.StopInstances invocation
	expectedStopInstancesInput := &ec2.StopInstancesInput{
		InstanceIds: []*string{
			&mockInstanceId,
		},
	}

	// Expect a call to ec2 StopInstances
	mockEc2.On("StopInstances", expectedStopInstancesInput).Return(
		&ec2.StopInstancesOutput{},
		nil,
	).Once()

	// Create CloudformationUtil which is the struct being tested
	cfnUtil, err := awsutil.NewCloudformationUtil(mockCfn, mockEc2)
	assert.NoError(t, err, "Error creating NewCloudformationUtil")

	// Tell it to stop all EC2 instances in the fake Cloudformation Stack
	cfnUtil.StopEC2Instances("fake_stack")

	// assert that all expectations met
	mockCfn.AssertExpectations(t)
	mockEc2.AssertExpectations(t)

}

func TestStartEc2InstanceStackResource(t *testing.T) {

	mockInstanceId := "i-mock"

	cfnUtil, _, mockEc2 := NewMockCloudformationUtil()

	// The mock ec2 API is expecting to get this as the parameter to
	// the ec2Api.StartInstances invocation
	expectedStartInstancesInput := &ec2.StartInstancesInput{
		InstanceIds: []*string{
			&mockInstanceId,
		},
	}

	mockEc2.On("StartInstances", expectedStartInstancesInput).Return(
		&ec2.StartInstancesOutput{},
		nil,
	).Once()

	stackResource := cloudformation.StackResource{
		ResourceType:       awsutil.StringPointer(awsutil.AWS_EC2_INSTANCE),
		PhysicalResourceId: &mockInstanceId,
	}

	err := cfnUtil.StartEc2InstanceForStackResource(stackResource)
	assert.NoError(t, err, "Error calling StartEc2InstanceStackResource")

	mockEc2.AssertExpectations(t)

}

func TestInCloudformationHappyPath(t *testing.T) {

	// The mock instance id which is part of a cloudformation stack
	mockInstanceId := "i-mockInstanceId"
	mockStackName := "mockstackname"
	mockLogicalResourceId := "mockLogicalResourceId"
	mockStackId := "i-mockstackid"

	cfnUtil, mockCfn, mockEc2 := NewMockCloudformationUtil()
	log.Printf("Created %v %v %v", cfnUtil, mockCfn, mockEc2)

	// mock cloudformation response which contains the physical resource ID
	// corresponding to the mock instance
	mockCfn.On("DescribeStackResources", mock.Anything).Return(
		&cloudformation.DescribeStackResourcesOutput{
			StackResources: []*cloudformation.StackResource{
				{
					ResourceType:       awsutil.StringPointer(awsutil.AWS_EC2_INSTANCE),
					PhysicalResourceId: &mockInstanceId,
					StackId:            &mockStackId,
					LogicalResourceId:  &mockLogicalResourceId,
					StackName:          &mockStackName,
				},
				{
					// since a DescribeStackResources returns _all_ resources in a stack,
					// not just the matching resource, throw in some fake resources
					// along with the instance resource
					ResourceType:       aws.String("AWS::EBS"),
					PhysicalResourceId: aws.String("PhysicalResourceId"),
					StackId:            &mockStackId,
					LogicalResourceId:  aws.String("LogicalResourceId"),
					StackName:          &mockStackName,
				},
			},
		},
		nil,
	).Once()

	in, stackId, stackName, err := cfnUtil.InCloudformation(mockInstanceId)
	assert.True(t, in)
	assert.NoError(t, err, "Got unexpected error")
	assert.Equal(t, stackId, mockStackId)
	assert.Equal(t, stackName, mockStackName)

}

func TestInCloudformationNotInStackCFNResponse(t *testing.T) {

	// The mock instance id which is part of a cloudformation stack
	mockInstanceId := "i-mockInstanceId"

	cfnUtil, mockCfn, mockEc2 := NewMockCloudformationUtil()
	log.Printf("Created %v %v %v", cfnUtil, mockCfn, mockEc2)

	// mock cloudformation response which is a broken cloudformation and returns
	// a stack resource which does not have a stackname or stackid
	mockCfn.On("DescribeStackResources", mock.Anything).Return(
		&cloudformation.DescribeStackResourcesOutput{
			StackResources: []*cloudformation.StackResource{
				{
					ResourceType:       awsutil.StringPointer(awsutil.AWS_EC2_INSTANCE),
					PhysicalResourceId: &mockInstanceId,
				},
			},
		},
		nil,
	).Once()

	in, _, _, err := cfnUtil.InCloudformation(mockInstanceId)
	assert.False(t, in)

	assert.Error(t, err, "Didn't get expected error")

}


func TestInCloudformationNoMatchingResources(t *testing.T) {

	// The mock instance id which is part of a cloudformation stack
	mockInstanceId := "i-mockInstanceId"

	cfnUtil, mockCfn, mockEc2 := NewMockCloudformationUtil()
	log.Printf("Created %v %v %v", cfnUtil, mockCfn, mockEc2)

	// mock cloudformation response which is a broken cloudformation and returns
	// a stack resource which does not have our expected instance id.
	mockCfn.On("DescribeStackResources", mock.Anything).Return(
		nil,
		fmt.Errorf("Stack for %v does not exist", mockInstanceId),
	).Once()

	in, _, _, err := cfnUtil.InCloudformation(mockInstanceId)
	assert.False(t, in)

	assert.NoError(t, err, "Unexpected error")

}

func NewMockCloudformationUtil() (*awsutil.CloudformationUtil, *mockcloudformation.CloudFormationAPIMock, *mockec2.EC2APIMock) {

	mockCfn := mockcloudformation.NewCloudFormationAPIMock()
	mockEc2 := mockec2.NewEC2APIMock()
	cfnUtil, err := awsutil.NewCloudformationUtil(mockCfn, mockEc2)
	if err != nil {
		panic(fmt.Sprintf("Error creating clouformation util: %v", err))
	}
	return cfnUtil, mockCfn, mockEc2

}