Become an AWS pro by getting hands-on with API Gateway. Developed by AWS Solution Certified Architects, you’ll build secure apps, integrate services, and create a chat app. No setup, no cleanup, no hassle.

awsdocker.tar.gz

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AWS CLI

AWS CLI-Ehtesham

API Gateway is an important component of the AWS serverless stack and has great potential to enable low latency, low-cost, and secure applications. This course takes you through all aspects of the AWS API Gateway and contains ready-to-use code snippets to implement different patterns of serverless API development in AWS. 

You’ll learn core concepts and get hands-on experience with core API Gateway capabilities. You’ll also dive deep into data mapping and WebSocket APIs and build a fully functional multi-user chat application with WebSocket API. You’ll learn about various services that can integrate with the API Gateway. Throughout the course, you’ll use IaC to provision resources, coupled with an introduction to CloudFormation. You’ll conclude the course by building a fully functional chat application with a bot that listens to the conversation and sends random jokes when asked.

Through detailed lessons covering theoretical and practical knowledge, this course helps you master the AWS API Gateway service.

AWS API Gateway: The Unsung Warrior

# Lambda function
AWS introduced Lambda functions in 2014. It was a new concept in computing that revolutionized application development.

All other architecture paradigms waste a lot of developer time and effort in set up and maintenance of the servers and development of the supporting code, or the boilerplate code.

Different cloud offerings like Infrastructure as a Service or Platform as a Service progressively remove parts of our load. That said, many non-business tasks remain with the developer.

Additionally, traditional forms of cloud computing require planning and provisioning. We have to provision the EC2 servers with the appropriate capacity. We’re always at risk of provisioning too little or too much.

Lambda functions resolve all these problems. Now, we only worry about the code with the required business logic. Amazon manages the rest of the job.

# Hello world
Let’s get started by creating a Lambda function. Following the traditions of software development, let’s start with a Hello World.

The code below implements an API using a simple Lambda function that returns “Hello World” as the response.


/**
 * This code is deployed as the Lambda function in AWS. 
 * It just returns the simple string Hello World.
 */

exports.handler = async(event, context) => {
  return "Hello World";
};



#!/bin/sh -v

# -----------------------------------------------------------------
# Configure the AWS CLI to let it communicate with your account
# -----------------------------------------------------------------
aws configure set aws_access_key_id $aws_access_key_id
aws configure set aws_secret_access_key $aws_secret_access_key
aws configure set region us-east-1

# -----------------------------------------------------------------
# Delete any old deployments
# -----------------------------------------------------------------
# 1. Trigger CloudFormation stack delete
# 2. Wait for the stack to be deleted 
aws cloudformation delete-stack --stack-name  EducativeCourseApiGateway
aws cloudformation wait stack-delete-complete --stack-name EducativeCourseApiGateway

# -----------------------------------------------------------------
# Deploying a Lambda Function requires two steps.
# -----------------------------------------------------------------
# 1. Create a deployment ZIP file and upload it to S3
# 2. Deploy the CloudFormation template that picks this ZIP file and makes a Lambda function
#
# The below code will do both

# -----------------------------------------------------------------
# Cleanup anything that is left over from the last deployment.
# -----------------------------------------------------------------
rm -f *.zip 

# -----------------------------------------------------------------
# Create a unique S3 Bucket. The name of S3 bucket is derived from the access key. So it has to be unique
# -----------------------------------------------------------------
bucket=`echo $aws_access_key_id | tr '[:upper:]' '[:lower:]'`
aws s3 mb s3://educative.${bucket} --region us-east-1

# -----------------------------------------------------------------
# It is important that this zip file has a new name everytime we deploy. Else, the new code is not picked.
# We start by creating a random string. This is an important part of CloudFormation deployments.
# -----------------------------------------------------------------
RAND=$(dd if=/dev/random bs=8 count=1 2>/dev/null | od -An -tx1 | tr -d ' \t\n')

# -----------------------------------------------------------------
# Build the zip file that we want to deploy. At this point, we include the index.js in our 
# -----------------------------------------------------------------
zip -r ${RAND}.zip index.js

# -----------------------------------------------------------------
# Upload the lambda zip file to the S3 bucket. 
# -----------------------------------------------------------------
aws s3 cp ${RAND}.zip s3://educative.${bucket}

# -----------------------------------------------------------------
# With everything ready, we initiate the CloudFormation deployment.
# -----------------------------------------------------------------
aws cloudformation deploy \
    --template-file template.yml \
    --stack-name EducativeCourseApiGateway \
    --capabilities CAPABILITY_NAMED_IAM \
    --parameter-overrides DeployId="$RAND" SourceCodeBucket="educative.${bucket}" \
    --region us-east-1

# -----------------------------------------------------------------
# To test the Lambda Function, find out the URL of our Lambda Function
# -----------------------------------------------------------------
url=`aws lambda get-function-url-config --function-name EducativeHelloWorld --region us-east-1 | jq -r ".FunctionUrl"`

# -----------------------------------------------------------------
# Invoke the Lambda Function URL using curl
# -----------------------------------------------------------------
echo $url
curl $url




AWSTemplateFormatVersion: "2010-09-09"
Parameters:
  DeployId:
    Type: String
    Default: afsf34sfdg
  SourceCodeBucket:
    Type: String
    Default: afsf34sfdg
Resources:
  HelloWorldLambda:
    Type: AWS::Lambda::Function
    Properties:
      Handler: index.handler
      Role: !GetAtt LambdaExecutionRole.Arn
      FunctionName: EducativeHelloWorld
      Code:
        S3Bucket:
          Ref: SourceCodeBucket
        S3Key: !Sub "${DeployId}.zip"
      Runtime: nodejs16.x
      Timeout: 3
      MemorySize: 128
  LambdaPermission:
    Type: AWS::Lambda::Permission
    Properties: 
      Action: lambda:InvokeFunctionUrl
      FunctionName: !GetAtt HelloWorldLambda.Arn
      FunctionUrlAuthType: NONE
      Principal: "*"
  LambdaUrl:
    Type: AWS::Lambda::Url
    Properties: 
      AuthType: NONE
      TargetFunctionArn: !GetAtt HelloWorldLambda.Arn
  LambdaExecutionRole:
    Type: AWS::IAM::Role
    Properties:
      RoleName: EducativeLambdaRole
      AssumeRolePolicyDocument:
        Version: "2012-10-17"
        Statement:
          - Effect: Allow
            Principal:
              Service:
                - lambda.amazonaws.com
                - apigateway.amazonaws.com
            Action:
              - sts:AssumeRole
      Path: "/"
      ManagedPolicyArns:
        - !Join 
            - ''
            - - 'arn:aws:iam::'
              - !Ref 'AWS::AccountId'
              - ':policy/APIGatewayCustomPolicy'



Introduction to API Gateway

API Gateway: High Level View

Getting Started with AWS API Gateway

API Gateway: Basic Configurations

Data Mapping Deep Dive

Leveraging AWS API Gateway for Public API Integration

Websocket Deep Dive

AWS Service Integration Deep Dive

Integrating AWS Services with API Gateway

Appendix

API Gateway Evaluation

Chat Application with Jokes Bot

Building a Chat Application Using Lambda Function and API Gateway

Create a Lambda Function

Lambda function