lambda-updater

A small CLI tool to update one or more AWS Lambda functions from a AWS CloudFormation template that share the same code artifact.

This is useful if you have a huge CloudFormation stack with multiple Lambda functions using the same code artifact but you don't want to re-deploy the whole stack just because you've added one line in a Lambda function. Use this to quickly upload a new version of your function's code.

Notes

• Before you use lambda-updater, make sure that your AWS CLI is installed and configured.
• Before you use lambda-updater, make sure that your CloudFormation stack exists, i.e. you've successfully deployed it at least once.

Install

npm

npm install -g lambda-updater

yarn

yarn global add lambda-updater

Example

lambda-updater \
    --cfn cfn.yml \
    --stack java-starter \
    --target target/target.jar \
    --functionName JavaExampleFunction \
    --useS3 shesse-lambdas

Usage

After that, just use the following command and all Java or NodeJS functions from your CloudFormation template get updated:

lambda-updater
   --cfn path
   --stack stack-name
   --target jsOrJarFile
   [--functionName name]
   [--useS3 bucketName]
   [--debug]

--cfn the relative path to your CloudFormation template

--stack the stack name for your CloudFormation template

--target a path to the JS or JAR file containing all your function code; just the functions matching the target type will be updated (might be useful if you're using Java and NodeJS functions in one project)

--functionName optional: if you just want to update one single function, provide the logical function name (= resource id in your CloudFormation template)

--useS3 optional: pass a bucket name and your target file will be uploaded to S3 first. This is useful and faster if your artifact file is quite large for a Lambda function (> 10MB). Target file will be uploaded to [LAMBDA_BUCKET]/_lambda-updater/[FILENAME]. Please consider the limitations on this approach.

--debug optional: prints out some further debug logs.

Note

The logical function name is what you define in your CloudFormation template. Example:

AWSTemplateFormatVersion: '2010-09-09'

Resources:
  YourLogicalFunctionName:
    Type: AWS::Serverless::Function
    Properties:
      # ...

If you have a function defined in your template which hasn't been deployed yet, it will be ignored and of course not updated. In this case there might be a different amount of functions in the logs which have been found and which actually have been updated.

Author

Sebastian Hesse

License

MIT License

Copyright (c) 2017 Sebastian Hesse

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.