delete-function command doesn't respect AWS_DEFAULT_PROFILE variable

[tolache]

Describe the bug

If you are not using a default profile set in ~/.aws/config and rely on setting the AWS_DEFAULT_PROFILE environment variable to select the required profile, the dotnet lambda delete-function command will fail unless a profile is specified inline.

Regression Issue

• Select this option if this issue appears to be a regression.

Expected Behavior

The function is deleted successfully.

Current Behavior

dotnet lambda delete-function --function-name <my_function_name> produces output indicating an error:

Amazon Lambda Tools for .NET Core applications (5.12.3)
Project Home: https://github.com/aws/aws-extensions-for-dotnet-cli, https://github.com/aws/aws-lambda-dotnet

Error deleting Lambda function: Unable to get IAM security credentials from EC2 Instance Metadata Service.

Reproduction Steps

1. Ensure that there is not default credentials in .aws/credentials.
2. Set AWS_DEFAULT_PROFILE to <my_non_default_profile>.
3. Ensure aws sts get-caller-identity works, i.e., provides output like

   {
       "UserId": "<my_user_id>",
       "Account": "<my_account_id>",
       "Arn": "arn:aws:iam::<my_account_id>:user/<my_non_default_profile>"
   }
   

4. Deploy a function using dotnet lambda deploy-function.
5. Try to delete the function using dotnet lambda delete-function --function-name <my_function_name>.

Possible Solution

The workaround is to specify the non-default profile inline:

dotnet lambda delete-function --function-name TunnelGPT --profile <my_non_default_profile>

Additional Information/Context

No response

AWS .NET SDK and/or Package version used

Amazon Lambda Tools for .NET Core applications (5.12.3)

Targeted .NET Platform

.NET 8

Operating System and version

Windows 11

[ashishdhingra]

@tolache Good afternoon. Thanks for opening the issue. AWS Extensions for .NET CLI tooling relies on AWS SDK for .NET for profile and credential resolution. Please refer AWS SDK for .NET: Credential and profile resolution, which mentions how AWS SDK for .NET resolves credentials where it does inspect AWS_PROFILE.

Environment variables supported by most SDKs are listed here.

Please share the following:

• Have you tried using AWS_PROFILE environment variable?
• Point us to reference where it states that AWS_DEFAULT_PROFILE environment variable should be supported.

Thanks,
Ashish

[tolache]

Confirmed: it works fine with the AWS_PROFILE environment variable. Sorry for the noise and thanks for looking into this, @ashishdhingra.