DIY Netlify _redirects

_redirects

# Place this file in the route of your S3 bucket
# https://www.npmjs.com/package/middy-reroute

# Redirect with 301
/home           /
/google         https://www.google.com
 
# Redirect with 302
/my-redirect    /             302
 
# Rewrite a path
/pass-through   /index.html   200
/*              /index.html   200
 
# Custom 404
/ecommerce      /closed       404
 
# Placeholders
/news/:year/:month/:date/:slug    /blog/:date/:month/:year/:slug
 
# Splats
/news/*   /blog/:splat
 
# Proxying
/api/*  https://api.example.com/:splat  200
 
# Country
/  /china   302  Country=cn,hk,tw
/  /israel  302  Country=il
 
# Language
/china/*  /china/zh-cn/:splat  302  Language=zh

lambda.js

'use strict';

const middy = require('middy');
const { reroute } = require('middy-reroute'); // https://www.npmjs.com/package/middy-reroute

const handler = middy((event, context, cb) => {
  const request = !!event.Records ? event.Records[0].cf.request : event;
  cb(null, request);
}).use(
  reroute({
    cacheTtl: 2,
  }),
);

module.exports = { handler };

template.yaml

Transform: AWS::Serverless-2016-10-31

Globals:
  Function:
    Runtime: nodejs10.x
    Handler: index.handler

Parameters:
  DomainParam:
    Type: String
    Description: Domain to be extended with subdomains Eg. domain.com or sub.domain.com
  SSLCertARN:
    Type: String
    Description: WildCard SSL Certificate ARN

Resources:
  DefaultBucket:
    Type: AWS::S3::Bucket
  DefaultBucketPolicy:
    Type: AWS::S3::BucketPolicy
    Properties:
      Bucket:
        Ref: DefaultBucket
      PolicyDocument:
        Version: 2012-10-17
        Statement:
          Effect: Allow
          Principal:
            AWS: !GetAtt OriginRequestRole.Arn
            CanonicalUser: !GetAtt CloudfrontOAI.S3CanonicalUserId
          Action:
            - s3:ListBucket
            - s3:GetObject
          Resource:
            - !Sub arn:aws:s3:::${DefaultBucket}
            - !Sub arn:aws:s3:::${DefaultBucket}/*
  OriginRequestFunction:
    Type: AWS::Serverless::Function
    Properties:
      CodeUri: src/originrequest
      MemorySize: 512
      AutoPublishAlias: live
      Role: !GetAtt OriginRequestRole.Arn
  OriginRequestLogGroup:
    Type: AWS::Logs::LogGroup
    Properties:
      LogGroupName: !Sub /aws/lambda/${OriginRequestFunction}
      RetentionInDays: 3
  OriginRequestRole:
    Type: AWS::IAM::Role
    Properties:
      Path: /
      RoleName: !Sub ${AWS::StackName}-originrequest-role
      AssumeRolePolicyDocument:
        Version: 2012-10-17
        Statement:
          - Effect: Allow
            Principal:
              Service:
                - lambda.amazonaws.com
                - edgelambda.amazonaws.com
            Action: sts:AssumeRole
      Policies:
        - PolicyName: !Sub ${AWS::StackName}-originrequest-role
          PolicyDocument:
            Version: 2012-10-17
            Statement:
              - Effect: Allow
                Action:
                  - logs:CreateLogGroup
                  - logs:CreateLogStream
                  - logs:PutLogEvents
                  - logs:DescribeLogStreams
                Resource: arn:aws:logs:*:*:*
  CloudfrontOAI:
    Type: AWS::CloudFront::CloudFrontOriginAccessIdentity
    Properties:
      CloudFrontOriginAccessIdentityConfig:
        Comment: !Sub Created for ${AWS::StackName}
  CDN:
    Type: AWS::CloudFront::Distribution
    Properties:
      DistributionConfig:
        Aliases:
          - !Sub "*.${DomainParam}"
        ViewerCertificate:
          AcmCertificateArn: !Ref SSLCertARN
          SslSupportMethod: sni-only
          MinimumProtocolVersion: TLSv1.2_2018
        Enabled: true
        HttpVersion: http2
        PriceClass: PriceClass_All
        IPV6Enabled: true
        DefaultCacheBehavior:
          AllowedMethods:
            - DELETE
            - GET
            - HEAD
            - OPTIONS
            - PATCH
            - POST
            - PUT
          CachedMethods:
            - GET
            - HEAD
          Compress: true
          ForwardedValues:
            QueryString: true
            Cookies:
              Forward: none
            Headers:
              - Host
              - CloudFront-Viewer-Country
              - Accept-Language
          DefaultTTL: 0
          MaxTTL: 0
          MinTTL: 0
          TargetOriginId: WebsiteBucketOrigin
          ViewerProtocolPolicy: redirect-to-https
          LambdaFunctionAssociations:
            - EventType: origin-request
              LambdaFunctionARN: !Ref OriginRequestFunction.Version
        Origins:
          - DomainName: !GetAtt DefaultBucket.DomainName
            Id: WebsiteBucketOrigin
            S3OriginConfig:
              OriginAccessIdentity: !Sub origin-access-identity/cloudfront/${CloudfrontOAI}