能否在Serverless.yml中使用AWS CloudFormation的Mappings段？

Absolutely—you can include CloudFormation-style Mappings sections in your serverless.yml file, but you need to place them correctly and fix a small YAML formatting issue in your example first.

First, Fix the YAML Syntax #

Your sample Mappings has a minor formatting problem: YAML requires a space after the colon in key-value pairs. So instead of 56565d644801:true, it should be 56565d644801: true. This might seem trivial, but it’ll cause parsing errors if omitted.

Correct Placement in serverless.yml #

Serverless Framework converts your serverless.yml into a CloudFormation template under the hood, so it supports embedding native CloudFormation top-level elements like Mappings—but you need to nest them under the resources block, alongside Resources (if you have any custom CloudFormation resources).

Here’s your corrected example:

service: my-example-service

functions:
  MyFunction:
    handler: src/MyFunction/func.lambda_handler
    role: MyRole
    events:
      - schedule:
          rate: rate(12 hours)
          enabled:
            Fn::FindInMap:
              - accounts
              - !Ref AWS::AccountId

resources:
  Mappings:
    accounts:
      56565d644801: true
      986958470041: true
      090960219037: true
      05166767667: false

How It Works #

When you deploy or package your service, Serverless will inject the Mappings block directly into the generated CloudFormation template. The Fn::FindInMap (or its shorthand !FindInMap) will then correctly look up whether the schedule should be enabled based on your current AWS account ID.

Quick Validation Tip #

To confirm everything is set up correctly, run serverless package and check the generated template at .serverless/cloudformation-template-update-stack.json. You’ll see your Mappings included at the top level, and the enabled field for your schedule will reference it properly.

Just make sure you’re using a modern version of Serverless Framework—older versions might have limited support for native CloudFormation elements, but all recent releases handle this seamlessly.

内容的提问来源于stack exchange，提问作者José Enrique Hernández