Developing on AWS

AWS EC2 Instance Metadata

• AWS EC2 Instance Medata is powerful but one of the least known features to developers
• It allows AWS EC2 instances to “learn about themselves” without using an IAM role for that purpose
• THe URL is http://169.254.169.254/latest/meta-data
• You can retrieve the IAM Role name from the metadata, but you cannot retrieve the IAM policy.
• Metadata = Infor about the EC2 instance
• Userdata = launch script of the EC2 instance

  AWS SDK Overview

• What if you want to perform actions on AWS directly from your applications code? (without using the CLI)
• You can use an SDK (software development kit) !
• Official SDKs are…
  • Java
  • .NET
  • Node.js
  • PHP
  • Python (named boto3 / botocore)
  • Go
  • Ruby
  • C++

    AWS SDK Overview

• We have to use the AWS SDK when coding against AWS Services such as DynamoDB
• Fun fact… the AWS CLI uses the Python SDK (boto3)
• The exam experts you to know when you should use an SDK
• We’ll pratice the AWS SDK when we get to the Lamba functions
• Good to know: if you don’t specify or configure a default region, then us-east-1 will be chosen by default