I ran into the following error while using the AWS SAM Cli:
Error: Invalid value for "--parameter-overrides": ParameterKey=PURPLE_FROG,ParameterValue=CatBreeds is not in valid format. It must look something like 'ParameterKey=KeyPairName,ParameterValue=MyKey ParameterKey=InstanceType,ParameterValue=t1.micro'
This is the command I was running:
sam local start-api --parameter-overrides "ParameterKey=PURPLE_FROG,ParameterValue=CatBreeds"
The error message is unfortunately very misleading. After a fair bit of testing I found that the cause is actually the underscore in the parameter key and has nothing to do with the command format. Renaming all of the parameters to something like “PURPLEFROG” works.
The solution turned out to be pretty straight-forward. The region on the cli-config was set incorrectly. For example, mine was set to “Sydney” instead of “ap-southeast-2”. Type “aws configure list” to check what yours is set to.