Is there a way to retrieve ARN of a resource through AWS SDK for Go? I created a couple of tables in DynamoDB and I want to retrieve the ARNs.
The ARN format:
arn:aws:service:region:account-id:resource-type:resource-id
How to retrieve the account-id and region via SDK for Go?
There is no generic way to get region from AWS SDK. By generic, here we consider simple code that returns a correct AWS region for your service deployed to ANY environment.
AWS assumes the opposite process. As a client, you are expected to know where your AWS resources deployed, and you have to inject region into an app that connects to AWS.
Think about your code running on your local machine in Europe, accessing AWS DynamoDB deployed in us-east-2 region, or code that needs to copy data from DB in region1 to DB in region2. In both these cases, the application cannot get the correct region without a hint.
In many cases, though, the environment where your code is deployed can provide that hint.
A few examples:
For local environment, you can configure default region for AWS SDK - https://docs.aws.amazon.com/cli/latest/userguide/cli-configure-quickstart.html#cli-configure-quickstart-region. Your service picks up that region if you create client using config.LoadDefaultConfig
Another example is running your service on EC2. EC2 provides AWS metadata that includes current region and account. Current region can be requested using client.GetMetadata. GetInstanceIdentityDocument API returns both Region and Account ID.
If you control how your service is deployed, you can try to get current Region and Account ID from environment, otherwise common practice is setting ENV variables with Region and Account ID when you deploy your code.
