AWS: API, Dynamo and Lambda

Review, Research, and Discussion

What are serverless functions?

its a code that executed directly in cloud without thinking of maintaining servers.

If you were to create a system that emulated Lambda functions, how would you do it?

only you have to write your code inside handler function for Lambda either online or locally and then upload the code.
after that you have to trigger this Lambda function with other services to execute it.

Describe how a CDN works

it is a group of servers that connected together, but each one of them in different location.
when a user hit a request, then the nearest server to the user’s region will response to it.

Document the following Vocabulary Terms

Serverless Functions it’s a code that executed directly in cloud without thinking of maintaining servers.

Cloud Storage a service that allows you to save your static data online and use them when ever you want.

CDN Content delivery network, it is a group of servers that connected together, but each one of them in different location. when a user hit a request, then the nearest server to the user’s region will response to it.

Preparation Materials

AWS API Gateway Overview

Amazon API Gateway is a managed service that allows developers to define the HTTP endpoints of a REST API or a WebSocket API and connect those endpoints with the corresponding backend business logic. It also handles authentication, access control, monitoring, and tracing of API requests.
API Gateway mostly used with serverless functions to replace API servers.
it run Lambda functions to generate HTTP API responses.
it can publish SNS notifications when an HTTP API endpoint is accessed.
API Gateway provide authentication and authorization for your HTTP APIs.

advantages of using API Gateway AWS :

response to HTTP API requests.
response to WebSocket requests.
using AWS cognito that will check the authorization for your app, then no need to use your own auth.
using cloudWatch, X-Ray and another logging AWS services to simplify the debugging of your API requests.

dissadvantages of using API Gateway :

in some cases, response time will be slow.
Payload size : 10 MB
Integration timeouts : from 50 ms to 29 sec
Regional APIs : 600 regional API
but maybe you can enhance some of these limits if contacted the AWS support.

AWS API Gateway

Amazon API Gateway is a fully managed service that makes it easy for developers to create, publish, maintain, monitor, and secure APIs at any scale.

AWS DynamoDB Guide

DynamoDB is a hosted NoSQL database offered by Amazon Web Services (AWS).
DynamoDB good for:
- Applications with large amounts of data and strict latency requirements (up to 100 TBs)
- Serverless applications using AWS Lambda
- Data sets with simple, known access patterns

AWS DynamoDB

Amazon DynamoDB is a key-value and document database that delivers single-digit millisecond performance at any scale. It’s a fully managed, multi-region, multi-active, durable database with built-in security, backup and restore, and in-memory caching for internet-scale applications. DynamoDB can handle more than 10 trillion requests per day and can support peaks of more than 20 million requests per second.
very fast response (in milli-seconds).
it can handle a huge amount of requests togother.

Dynamoose

Dynamoose is a modeling tool for Amazon’s DynamoDB. Dynamoose is heavily inspired by Mongoose, which means if you are coming from Mongoose the syntax will be very familiar.
it is a package that we have to install on our terminals to control the AWS DynamoDB service to use NoSQl database.
installation command :

npm install dynamoose

## External resources :