SDK: Software Development Kit

If you want to perform actions on AWS directly from your application's code without using a CLI, you can use an SDK

Official SDKs:

Java
.NET
Node.js
PHP
Python
Ruby
C++

SDK Takeaways

AWS SDK are required when coding against AWS Services such as DynamoDB
Fact: AWS CLI uses the Python SDK (boto3)
The exam expects you to know when you should use an SDK
If you don’t specify or configure a default region, then us-east-1 will be chosen by default

SDK Credentials Security

It’s recommend to use the default credential provider chain
The default credential provider chain works seamlessly with:
- AWS credentials at ~/.aws/credentials (only on our computers or on premise)
- Instance Profile Credentials using IAM Roles (for EC2 machines, etc...)
Environment variables (AWS_ACCESS_KEY_ID, AWS_SECRET_ACCESS_KEY)
Overall, NEVER EVER STORE AWS CREDENTIALS IN YOUR CODE.
Use IAM Roles if working from within AWS Services to inherit credentials

Exponential Backoff

Any API that fails because of too many calls needs to be retried with Exponential Backoff
These apply to rate limited API
Retry mechanism is included in SDK API calls