Dynamically setting InstanceTypes with .ebextensions is not working

[jeran-urban]

Hello,

I am having an issue trying to dynamically set the EC2's InstancTypes per environment using .ebextensions.

I have tried multiple configurations and this Stack Overflow article has a good break down of the problem with more detailed examples and some troubleshooting provided as well.

working yaml example (hard coded):

    option_settings:
        aws:ec2:instances:
            InstanceTypes: t3.small # <-- hard coded works. 

example environment variable yaml used:

    option_settings:
        aws:elasticbeanstalk:application:environment:
            ENV_INSTANCE_TYPE: t3.small

failing yaml example (using getOptionSetting fn)

    option_settings:
        aws:ec2:instances:
            InstanceTypes: {"Fn::GetOptionSetting": {"Namespace": "aws:elasticbeanstalk:application:environment", "OptionName": "ENV_INSTANCE_TYPE"}}

returns error:

    ERROR   Not a comma-separated string or array: '{"Fn::GetOptionSetting":{"Namespace":"aws:elasticbeanstalk:application:environment","OptionName":"ENV_INSTANCE_TYPE"}}'

I also tried:

1. using custom resources.
2. using 't3.small,t3.medium' and splitting that into 2 separate variables for the env var.
3. using various attempts of joining/splitting the string in conjunction with the Fn::GetOptionSetting.

I do not see any issues referenced in the following documentation stating this should be an issue:

• functions usable in ebextensions
• fn::GetOptionSetting
• aws:ec2:instances -> InstanceTypes
• using custom resources

Is there something I am missing or is this not possible?

Any help with this would be greatly appreciated. Thank you.

[jeran-urban]

@0xab01 are you able to provide details/documentation for official sources as to what this is for / how it works / how it fixes this issue? I appreciate your input here, but blindly downloading and executing programs with no context/vetting would not be a viable solution.