constructor()

in lib/index.ts [75:143]

• 53 lines of code
• 7 McCabe index (conditional complexity)

  constructor(scope: Construct, id: string, props: S3ProxyFarmProps) {
    super(scope, id);

    this.websiteIndexDocument = props.websiteIndexDocument || this.websiteIndexDocument;
    this.allowedCIDRRanges = Array.isArray(props.allowedCIDRRanges) && props.allowedCIDRRanges.length ? props.allowedCIDRRanges : this.allowedCIDRRanges;

    this.proxyFarmSecurityGroup = new ec2.SecurityGroup(this, 'autoscaling-group-security-group', {
      vpc: props.vpc,
    });

    for (const cidrRange of this.allowedCIDRRanges) {
      this.proxyFarmSecurityGroup.addIngressRule(ec2.Peer.ipv4(cidrRange), ec2.Port.tcp(this.proxyPort), 'allow proxy access from CIDR range');  
    }

    const proxyFarmAsgProps = deepmerge({
      vpc: props.vpc,
      instanceType: ec2.InstanceType.of(ec2.InstanceClass.BURSTABLE2, ec2.InstanceSize.MICRO),
      machineImage: new ec2.AmazonLinuxImage(),
      associatePublicIpAddress: false,
      securityGroup: this.proxyFarmSecurityGroup,
      vpcSubnets: {
        subnetType: ec2.SubnetType.PRIVATE,
      },
      minCapacity: 1,
      maxCapacity: 3,
    }, props.autoScalingGroupProps || {}, {
      isMergeableObject: isPlainObject
    });

    this.proxyFarmAsg = new autoscaling.AutoScalingGroup(this, 'autoscaling-group', proxyFarmAsgProps);

    const cpuUtilizationScalingProps: autoscaling.CpuUtilizationScalingProps = deepmerge({
      targetUtilizationPercent: 80,
      cooldown: Duration.seconds(300),
    }, props.cpuUtilizationScalingProps || {}, {
      isMergeableObject: isPlainObject
    });

    this.proxyFarmAsg.scaleOnCpuUtilization('scaling-policy', cpuUtilizationScalingProps);

    // Configure Proxy (Nginx) on instance startup
    this.proxyFarmAsg.userData.addCommands(`
#!/bin/bash

amazon-linux-extras enable nginx1

yum -y install nginx

cat <<EOF > /etc/nginx/conf.d/reverse-proxy.conf
server {
  listen ${this.proxyPort};
  listen [::]:${this.proxyPort};

${this.allowedCIDRRanges.map((cidrRange) => `  allow ${cidrRange};`).join('\n')}
  deny all;

  location = / {
    proxy_pass ${props.websiteBucket.bucketWebsiteUrl}/${this.websiteIndexDocument};
  }

  location / {
    proxy_pass ${props.websiteBucket.bucketWebsiteUrl};
  }
}
EOF

service nginx restart
    `);
  }