lambda function 未在 AWS 中使用 cloudformation 和管道进行更新

Question

I'm trying to build a pipeline to automate a lambda function deployment on AWS. I created a pipeline, a codebuild and needed IAM roles and integrated them with cloudformation.

here's my buildspec.yml:

version: 0.2
phases:
  install:
    runtime-versions:
      nodejs: 14
    commands:
      - echo "Installing from package.json"
      # - npm install
  pre_build:
    commands:
      - echo "Build on `date`"
      # - npm run test
  post_build:
    commands:
      - zip -r lambda.zip index.js template.yml
      - aws s3api put-object --bucket github-lambda-demo --key lambda.zip --body lambda.zip


artifacts:
  files:
    - template.yml
  discard-paths: yes

And this is my cloudformation template:

AWSTemplateFormatVersion: '2010-09-09'
Description: Template for Lambda Sample.
Resources:
  LambdaRole:
    Type: AWS::IAM::Role
    Properties:
      RoleName:
        Fn::Sub: lambda-role
      AssumeRolePolicyDocument:
        Statement:
          - Action:
            - sts:AssumeRole
            Effect: Allow
            Principal:
              Service:
              - lambda.amazonaws.com
        Version: 2012-10-17
      ManagedPolicyArns:
        - arn:aws:iam::aws:policy/AWSLambdaExecute
        - arn:aws:iam::aws:policy/AmazonS3FullAccess

  LambdaFunction:
    Type: AWS::Lambda::Function
    Properties:
      Code:
        S3Bucket: github-lambda-demo
        S3Key: lambda.zip
      Description: demo for lambda deployment
      FunctionName: github-lambda-demo
      Handler: index.handler
      PackageType: Zip
      # Layers: 
      #   - String
      MemorySize: 256
      Role:
        Fn::GetAtt:
          - LambdaRole
          - Arn
      Runtime: nodejs14.x
      Timeout: 300

All the steps are done quite right with no errors in codePipeline but my lambda function source is not being update as it should be.

Any help?!

Answer 1

This is expected behavior for Lambda Resource in cloudformation, Straight from docs :

Changes to a deployment package in Amazon S3 are not detected automatically during stack updates. To update the function code, change the object key or version in the template.

So, typically two options:

First option using versioned S3 Bucket :

• Enable versioning of S3 bucket where artifact is stored.
• put-object cli you have used will return the version of the object.
• Store the version in ssm parm or use a custom cloud formation resource to get latest version of an s3 object in cloudformation.

Second option using ssm parameter

• Suffix artifact name with a version (or even the git sha) before writing to S3.
• Store the version in an SSM parameter in build process itself.
• Grab the version from SSM parameter in cloudformation.