A valid option to satisfy the declaration could not be found in serverless framework - serverless-framework

Question

I'm using serverless framework and using bitbucket-pipeline to configure CI/CD.
I have the following configuration in the serverless.yml file
provider:
name: aws
runtime: nodejs10.x
region: ${opt:region, ${env:AWS_REGION, 'ap-south-1'}}
memorySize: ${opt:memory, ${env:MEMORY_SIZE, 512}}tracing:
apiGateway: ${env:TRACING_API_GATEWAY, true}
I want to be able to pass the variables from the CLI as well as environment variables.
I have set up environment variable for AWS_REGION in the bitbucket pipeline variables but not for MEMORY_SIZE as want to use the default value.
But this gives error while running the pipeline.
Serverless Warning --------------------------------------
A valid option to satisfy the declaration 'opt:region,ap-south-1' could not be found.
Serverless Warning --------------------------------------
A valid environment variable to satisfy the declaration 'env:MEMORY_SIZE,512' could not be found.
Serverless Warning --------------------------------------
A valid environment variable to satisfy the declaration 'env:TRACING_API_GATEWAY,true' could not be found.

Answer 1

First, those are warnings not errors. A Serverless error would be something like:
Serverless Error ---------------------------------------
Trying to populate non string value into a string for variable ${opt:stage}. Please make sure the value of the property is a string.
This specific error happens because in the custom tag I've declared: var: ${opt:stage}-something which should be changed like:
provider:
stage: ${opt:stage, 'local'}
custom:
var: ${self:provider.stage}-something
I think in your case, you need to update region like this:
region: ${opt:region, env:AWS_REGION, 'ap-south-1'}
I couldn't reproduce the last warning though but I reckon ENV variables should be defined in bitbucket-pipelines.yml (or similar CI pipeline YAML) under args or variables and then they can be accessed using ${env:VAR}.