Serverless Series - Serverless Services used in Demo

Let's have a closer look the 4 Serverless Services that will be used in today's Demo. 

Amazon S3

S3 is the massive storage and one of the back bones of AWS. Infact this was first service launched by AWS
How much data can I store?

The total volume of data and number of objects you can store are unlimited. Individual Amazon S3 objects can range in size from a minimum of 0 bytes to a maximum of 5 terabytes. The largest object that can be uploaded in a single PUT is 5 gigabytes. For objects larger than 100 megabytes, customers should consider using the Multipart Upload capability.

What storage classes does Amazon S3 offer?

Amazon S3 offers a range of storage classes designed for different use cases. There are three highly durable storage classes including 

• S3 Standard for general-purpose storage of frequently accessed data
• S3 Intelligent-Tiering storage class is designed to optimize costs by automatically moving data to the most cost-effective access tier, without performance impact or operational overhead. 
• S3 Standard - Infrequent Access for long-lived, but less frequently accessed data, 
• S3 One Zone-IA is for data that is accessed less frequently, but requires rapid access when needed. Unlike other S3 Storage Classes which store data in a minimum of three Availability Zones (AZs), S3 One Zone-IA stores data in a single AZ and costs 20% less than S3 Standard-IA. 
• S3 Glacier  is a secure, durable, and low-cost storage class for data archiving.
• S3 Glacier Deep Archive is Amazon S3’s lowest-cost storage class and supports long-term retention and digital preservation for data that won’t be regularly accessed. It is designed for customers — particularly those in highly-regulated industries, such as the Financial Services, Healthcare, and Public Sectors — that retain data sets for 7-10 years or longer to meet regulatory compliance requirements. 

S3 Storage Classes can be configured at the object level and a single bucket can contain objects stored in S3 Standard, S3 Intelligent-Tiering, S3 Standard-IA, and S3 One Zone-IA. For further reading on S3 Storage Classes, refer https://aws.amazon.com/s3/storage-classes/.

 Amazon CloudWatch

CloudWatch sits under Management Tools in AWS Console and can monitor any AWS Services – ALB, EBS, EC2, ELB, S3 etc

• Metrics - For example, basic host level metrics like CPU Utilization, DiskOps etc are monitored where OS level metrics like memory would need you to write custom metrics. Documentations are available for the same.
• Dashboards – Creates awesome dashboards to see what is happening with your AWS Environment. 
• Alarms – Allows you to set Alarms that notify you when particular thresholds are hit. 
• Events – CloudWatch events helps you to respond to state changes in your AWS resources  
• Logs – CloudWatch Logs helps you to aggregate, monitor, and store logs. 

Amazon API Gateway
Amazon API Gateway is an AWS service that enables you to create, publish, maintain, monitor, and secure your own APIs at any scale. You can create robust, secure, and scalable APIs that access AWS or other web services, as well as data stored in the AWS Cloud

• Support for stateful (WebSocket) and stateless (REST) APIs
• Integration with AWS services such as AWS Lambda, Amazon Kinesis, and Amazon DynamoDB
• There are two kinds of developers who use API Gateway: API developers and app developers.
• An API developer creates and deploys an API to enable the required functionality in API Gateway. The API developer must be an IAM user in the AWS account that owns the API.
• As an API developer, you can create and manage an API by using the API Gateway console, CLI, SDK or Cloud Formation Template
• An app developer builds a functioning application to call AWS services by invoking a WebSocket or REST API created by an API developer in API Gateway.
• The app developer is the customer of the API developer. The app developer does not need to have an AWS account, provided API is designed that way.

Together with AWS Lambda, API Gateway forms the app-facing part of the AWS serverless infrastructure

AWS Lambda

AWS Lambda is a compute service that lets you run code without provisioning or managing servers. AWS Lambda executes your code only when needed and scales automatically, from a few requests per day to thousands per second. You pay only for the compute time you consume - there is no charge when your code is not running. With AWS Lambda, you can run code for virtually any type of application or backend service - all with zero administration. AWS Lambda runs your code on a high-availability compute infrastructure and performs all of the administration of the compute resources, including server and operating system maintenance, capacity provisioning and automatic scaling, code monitoring and logging. 

• All you need to do is supply your code in one of the languages that AWS Lambda supports (currently Node.js, Java, C# and Python). 
• You can use AWS Lambda  
• (1) to run your code in response to events (Event Driven), such as changes to data in an Amazon S3 bucket or an Amazon DynamoDB table;  
• (2) to run your code in response to HTTP requests using Amazon API Gateway; or invoke your code using API calls made using AWS SDKs.  
• Lambda functions are independent but one lambda function can trigger other lambda functions 
• Lambda scales automatically and also can perform actions globally like copying files from S3 in one region to other region.

Pricing at high-level:

• S3 - new AWS customers receive 5 GB of Amazon S3 Standard storage, 20,000 Get Requests, 2,000 Put Requests, 15GB of data transfer in, and 15GB of data transfer out each month for one year.
• ~ 0.23/per GB update 50GB
• API Gateway 
• Rest API 
• Pay only for the API calls you receive and the amount of data transferred out
• For better performance and faster API execution, you can optionally provision a dedicated cache for each stage of your APIs. After you specify the size of the cache you require, you will be charged the following hourly rates for each stage’s cache, without any long-term commitments.
• Free Tier - 1M API CALLS RECEIVED | 1M MESSAGES | 750,000 CONNECTION MINUTES
• WebSocket APIs
• Pay only for messages sent and received and the total number of connection minutes. You may send and receive messages up to 128 kilobytes (KB) in size. Messages are metered in 32 KB increments. So, a 33 KB message is metered as two messages.
• For WebSocket APIs, the API Gateway free tier includes one million messages (sent or received) and 750,000 connection minutes for up to 12 months.
• AWS Lambda
• Lambda counts a request each time it starts executing in response to an event notification or invoke call, including test invokes from the console. You are charged for the total number of requests across all your functions.  
• Amazon CloudWatch
  • Basic Monitoring Metrics (at 5-minute frequency) where detailed monitoring Metrics (at 1-minute frequency) is charged
  • Example: EC2 Detailed Monitoring is priced at $2.10 per instance per month and goes down to $0.14 per instance at the lowest priced tier.) 

For the Sample that we are going to try today, trust me that it won’t incur any charge if you clean-up diligently :).