This is Gitlab-ci to update lambda code via gitlab. Used this to publish alexa skill.

.gitlab-ci.yml

stages:
  - deploy
variables:
  AWS_ACCESS_KEY_ID: "ABCD"              
  AWS_SECRET_ACCESS_KEY: "ABCD"
  AWS_DEFAULT_REGION: "us-east-1"
  NAME: "your-function-name"
  RUNTIME: "nodejs6.10"
  ROLE: "arn:aws:iam::000000000000:role/xxxxx"
  HANDLER: "index.handler"
  FILE: "fileb://your-file.zip"
  S3_PATH: "upload-path-to-s3-bucket-"
  S3_BUCKET: "s3-bucket-name"
  S3_KEY: "file-path-in-s3-bucket"
upload-to-lambda:
 image: salte/aws-lambda-deploy:latest
 stage: deploy
 script:
    - zip -r your-file.zip .
    - aws s3 ls
    - aws s3 cp your-file.zip $S3_PATH
    - aws lambda update-function-code --function-name $NAME --s3-bucket $S3_BUCKET --s3-key $S3_KEY