lambda

Lambda with e2e testing

Prerequisites:

• dedicated aws account for e2e testing
  • aws-e2e credentials file-> ~/.secret/aws-e2e.json
  • Setup Endly AWS Credentials
  • endly e2e runner (0.34.1+)

Running e2e tests with endly docker container

mkdir -p ~/e2e
mkdir -p ~/.secret
docker run --name endly -v /var/run/docker.sock:/var/run/docker.sock -v ~/e2e:/e2e -v ~/.secret/:/root/.secret/ -p 7722:22  -d endly/endly:latest-ubuntu16.04  

ssh root@127.0.0.1 -p 7722 ## password is dev

#### all operation now taking place in endly docker container

endly -v #to check version

endly -c=localhost  ## create localhost credentials with user root/dev
ls -al /root/.secret/localhost.json ## check encrypted credentials created

## generate aws-e2e.json  -> /root/.secret/aws.json  
### @aws-e2e.josn -> {"Region":"xxx", "Key":"yyy", "Secret":"zzz"}

#For use case 6 (Securing sensitive data) and 7 (Multi stack HTTP Gateway) apply prerequisites described in prerequisite.txt and remove skip.txt

cd /e2e
git clone https://github.com/adrianwit/serverless_e2e
cd  serverless_e2e/lambda/e2e
endly -r=run

Introduction

AWS Lambda is a serverless compute service that runs a provided code in response to events and automatically manages the underlying compute resources. The event can be fired by a specific trigger, which determines how and when your function executes.

References:

• Programming-model

Event/Trigger

Lambda entry point:

func main() {
	lambda.Start(handler)
}

where handler supports the following function signatures:

• func()
• func() error
• func(Event) error
• func() (Output, error)
• func(Event) (Output, error)
• func(context.Context) error
• func(context.Context, Event) error
• func(context.Context) (Output, error)
• func(context.Context, Event) (Output, error)

Pull/Push model lambda trigger configuration

1. Pull-based AWS services: Amazon Kinesis Data Streams and DynamoDB streams or Amazon SQS queues

   • trigger is configured within lambda via Event Source Mapping

2. Push based AWS services

   • trigger is configured within event source. For example, Amazon S3 provides the bucket notification configuration API
   • source event need necessary permissions to invoke a lambda function

References:

• Go Programming Model Handler Types
• invocation-modes

Examples

This project provides example for the following native mechanisms:

Direct Function Invocation

• HelloWorld
• E2E Use Case
  • endly -i=hello_world
• Handler Signature

    func() (Output, error)
    func(Event) (Output, error)

HTTP APIGateway

• LogInfo Source Code

• E2E Use Case

  • endly -i=logs_count

• Handler Signature

    func(context.Context, events.APIGatewayProxyRequest) (events.APIGatewayProxyResponse, error)

• APIGatewayProxyRequest

// APIGatewayProxyRequest contains data coming from the API Gateway proxy
type APIGatewayProxyRequest struct {
	Resource                        string                        `json:"resource"` // The resource path defined in API Gateway
	Path                            string                        `json:"path"`     // The url path for the caller
	HTTPMethod                      string                        `json:"httpMethod"`
	Headers                         map[string]string             `json:"headers"`
	MultiValueHeaders               map[string][]string           `json:"multiValueHeaders"`
	QueryStringParameters           map[string]string             `json:"queryStringParameters"`
	MultiValueQueryStringParameters map[string][]string           `json:"multiValueQueryStringParameters"`
	PathParameters                  map[string]string             `json:"pathParameters"`
	StageVariables                  map[string]string             `json:"stageVariables"`
	RequestContext                  APIGatewayProxyRequestContext `json:"requestContext"`
	Body                            string                        `json:"body"`
	IsBase64Encoded                 bool                          `json:"isBase64Encoded,omitempty"`
}

• Usage

func main() {
	lambda.Start(handleRequest)
}

func handleRequest(ctx context.Context, apiRequest events.APIGatewayProxyRequest) (events.APIGatewayProxyResponse, error) {
	request, err := newRequest(apiRequest)
	if err != nil {
		return handleError(err)
	}
	service := New() //you service
	response := service.CountLogs(request)
	responseJSON, err := json.Marshal(response)
	if err != nil {
		return handleError(err)
	}
	return events.APIGatewayProxyResponse{
		StatusCode: http.StatusOK,
		Body:       string(responseJSON),
	}, nil
}

func handleError(err error) (events.APIGatewayProxyResponse, error) {
	errorLogger.Printf("unable to process request %v", err)
	return events.APIGatewayProxyResponse{
		StatusCode: http.StatusInternalServerError,
		Body:       http.StatusText(http.StatusInternalServerError),
	}, nil
}

• References
  • Amazon API Gateway
  • Event Contract

S3 Storage

• FileMeta
• E2E Use Case
  • endly -i=filemeta
• Handler Signature

    func(context.Context, events.S3Event)

• Event types:

• s3:ObjectCreated:*
• s3:ObjectCreated:Put
• s3:ObjectCreated:Post
• s3:ObjectCreated:Copy
• s3:ObjectCreated:CompleteMultipartUpload
• s3:ObjectRemoved:*
• s3:ObjectRemoved:Delete
• s3:ObjectRemoved:DeleteMarkerCreated
• s3:ObjectRestore:Post
• s3:ObjectRestore:Completed
• s3:ReducedRedundancyLostObject

• S3Event

type S3Event struct {
	Records []S3EventRecord `json:"Records"`
}

type S3EventRecord struct {
	EventVersion      string              `json:"eventVersion"`
	EventSource       string              `json:"eventSource"`
	AWSRegion         string              `json:"awsRegion"`
	EventTime         time.Time           `json:"eventTime"`
	EventName         string              `json:"eventName"`
	PrincipalID       S3UserIdentity      `json:"userIdentity"`
	RequestParameters S3RequestParameters `json:"requestParameters"`
	ResponseElements  map[string]string   `json:"responseElements"`
	S3                S3Entity            `json:"s3"`
}

type S3UserIdentity struct {
	PrincipalID string `json:"principalId"`
}

• Event Contract

• References:

  • Using Lambda with S3
  • Using Lambda with S3 Example
  • NotificationHowTo
  • Setting Bucket Notification

Simple Queue Service

• FileMeta
• E2E Use Case
  • endly -i=msglog
• Handler Signature

    func(ctx context.Context, sqsEvent events.SQSEvent) error

• SQSEvent

type SQSEvent struct {
	Records []SQSMessage `json:"Records"`
}

type SQSMessage struct {
	MessageId              string                         `json:"messageId"`
	ReceiptHandle          string                         `json:"receiptHandle"`
	Body                   string                         `json:"body"`
	Md5OfBody              string                         `json:"md5OfBody"`
	Md5OfMessageAttributes string                         `json:"md5OfMessageAttributes"`
	Attributes             map[string]string              `json:"attributes"`
	MessageAttributes      map[string]SQSMessageAttribute `json:"messageAttributes"`
	EventSourceARN         string                         `json:"eventSourceARN"`
	EventSource            string                         `json:"eventSource"`
	AWSRegion              string                         `json:"awsRegion"`
}

• Event Contract

• References:

  • Using Lambda with Amazon SQS
  • Lambda Event Source Mapping

Simple Notification Service

• Aggregatio Source code
• E2E Use Case
  • endly -i=agg
• Handler Signature

    func(ctx context.Context, snsEvent events.SNSEvent) error

• SNSEvent

type SNSEvent struct {
	Records []SNSEventRecord `json:"Records"`
}

type SNSEventRecord struct {
	EventVersion         string    `json:"EventVersion"`
	EventSubscriptionArn string    `json:"EventSubscriptionArn"`
	EventSource          string    `json:"EventSource"`
	SNS                  SNSEntity `json:"Sns"`
}

type SNSEntity struct {
	Signature         string                 `json:"Signature"`
	MessageID         string                 `json:"MessageId"`
	Type              string                 `json:"Type"`
	TopicArn          string                 `json:"TopicArn"`
	MessageAttributes map[string]interface{} `json:"MessageAttributes"`
	SignatureVersion  string                 `json:"SignatureVersion"`
	Timestamp         time.Time              `json:"Timestamp"`
	SigningCertURL    string                 `json:"SigningCertUrl"`
	Message           string                 `json:"Message"`
	UnsubscribeURL    string                 `json:"UnsubscribeUrl"`
	Subject           string                 `json:"Subject"`
}

• Event Contract

• References:

  • Using Lambda with Amazon SNS

Securing sensitive data

• aws kms create-key

• aws kms create-alias

• aws ssm put-parameter --name "" --value '' --type SecureString --key-id alias/

• aws ssm get-parameters --names "" --with-decryption

• Data Transfer Source code

• E2E Use Case

  • apply prerequsites
  • endly -i=dstransfer

• References:

  • Managing-secrets-with-parameter-store-and-iam-roles

Multi stack HTTP Gateway

• Shopping Cart Source code
• E2E Use Case
  • apply prerequsites
  • endly -i=shopingcart

Virtual Private Cloud with aerospike and SQS

• Event aggregation in aerospike
• E2E Use Case
  • apply prerequsites
  • endly -i=aerospike_vpc

Error Handling

References:

• Errors