aws-lambda-layer-cli 1.4.1

CLI tool for creating and publishing AWS Lambda layers for Node.js and Python.

AWS Lambda Layer CLI Tool

A command-line tool for creating and publishing AWS Lambda layers for Node.js and Python.

Features

• Create Layers: Generate Lambda layer zip files for Node.js and Python
• Publish to AWS: Directly publish layers to AWS Lambda with IAM credentials
• Version Management: Support for package version specification
• Security: Input validation and sanitization
• Smart Naming: Automatic layer naming with package versions
• Multiple Packages: Support for multiple packages in a single layer
• Runtime Versioning: Specify Node.js or Python versions
• Package Managers: Support for npm (Node.js) and uv/pip (Python)
• AWS Profile Support: Use different AWS profiles for publishing
• Region Specification: Target specific AWS regions

Installation

Package managers (recommended)

These installs do not write to /usr/local and do not require sudo.

npm (Node.js)

npm i -g aws-lambda-layer-cli
aws-lambda-layer --help

pip (Python)

python -m pip install --user aws-lambda-layer-cli
aws-lambda-layer --help

uv (Python)

uv tool install aws-lambda-layer-cli
aws-lambda-layer --help

Linux/macOS

# Clone or download the repository
git clone <repository-url>
cd aws-lambda-layer-cli

# Run installation script (requires sudo)
sudo ./scripts/install.sh

The installation will:

• Copy scripts to /usr/local/lib/aws-lambda-layer
• Create a symlink in /usr/local/bin for global access
• Install shell completions for bash and zsh

Windows

Option 1: PowerShell (Recommended)

# One-liner installation
powershell -ExecutionPolicy ByPass -c "irm https://raw.githubusercontent.com/yukcw/aws-lambda-layer-cli/main/scripts/install.ps1 | iex"

Or download and run manually:

# Download the installer
Invoke-WebRequest -Uri "https://raw.githubusercontent.com/yukcw/aws-lambda-layer-cli/main/scripts/install.ps1" -OutFile "install.ps1"

# Run the installer (as Administrator)
.\install.ps1

This will:

• Download the tool to %USERPROFILE%\.aws-lambda-layer
• Add it to your PATH
• Create Windows wrapper scripts

Option 2: Manual Installation

1. Install prerequisites:

   • Git for Windows (includes Git Bash)
   • AWS CLI (for publish command)

2. Download the scripts from the repository

3. Extract to a directory and add to PATH

Requirements

• Linux/macOS: Bash shell
• Windows: Windows Subsystem for Linux (WSL) (recommended), or Git Bash/Cygwin
• AWS CLI: Required for publish command
• Node.js: Required for Node.js layer creation
• Python: Required for Python layer creation (uv recommended)
• zip: Required for creating zip archives

Note: If using WSL, ensure that AWS CLI, Node.js, Python, and zip are installed within WSL for proper functionality.

Uninstallation

Package managers

# npm
npm uninstall -g aws-lambda-layer-cli

# pip
python -m pip uninstall aws-lambda-layer-cli

# uv
uv tool uninstall aws-lambda-layer-cli

Linux/macOS

sudo ./scripts/uninstall.sh

Windows

Using PowerShell

# Download and run the uninstaller
Invoke-WebRequest -Uri "https://raw.githubusercontent.com/yukcw/aws-lambda-layer-cli/main/scripts/uninstall.ps1" -OutFile "uninstall.ps1"
.\uninstall.ps1

Or run directly without downloading:

powershell -ExecutionPolicy ByPass -c "irm https://raw.githubusercontent.com/yukcw/aws-lambda-layer-cli/main/scripts/uninstall.ps1 | iex"

Troubleshooting Windows Installation

If you encounter issues:

1. "bash: command not found"

   • Install Git for Windows or WSL
   • Restart PowerShell/Command Prompt after installation

2. "No such file or directory"

   • Try running: bash "$env:USERPROFILE\.aws-lambda-layer\aws-lambda-layer" --help
   • Or reinstall: powershell -ExecutionPolicy ByPass -c "irm https://raw.githubusercontent.com/yukcw/aws-lambda-layer-cli/main/scripts/install.ps1 | iex"

3. Permission issues

   • Run PowerShell as Administrator
   • Or run: Set-ExecutionPolicy -ExecutionPolicy RemoteSigned -Scope CurrentUser

Usage

Basic Syntax

# Create a local zip file
aws-lambda-layer zip --nodejs <packages> [options]
aws-lambda-layer zip --python <packages> [options]

# Publish directly to AWS
aws-lambda-layer publish --nodejs <packages> [options]
aws-lambda-layer publish --python <packages> [options]

Commands

• zip: Create and package a Lambda layer as zip file
• publish: Create and publish a Lambda layer to AWS (uses IAM credentials)
• help: Show help message

Runtime Options

• --nodejs, --node, -n: Create a Node.js Lambda layer
• --python, --py, -p: Create a Python Lambda layer
• --runtime=RUNTIME: Specify runtime (nodejs or python)

Common Options

• --name: Name for the output zip file / layer name
• --description: Description for the layer (publish command only)
• -h, --help: Show help message

AWS Options (publish command only)

• --profile: AWS CLI profile to use (default: default profile)
• --region: AWS region (e.g., us-east-1, ap-east-1)

Node.js Specific Options

• --node-version: Node.js version (default: 24)

Python Specific Options

• --python-version: Python version (default: 3.14)
• --no-uv: Use pip/venv instead of uv

Examples

Node.js Examples

Create Local Zip Files

# Single package with version
aws-lambda-layer zip --nodejs express@4.18.2

# Multiple packages with versions
aws-lambda-layer zip --nodejs express@4.18.2,axios@1.6.2,lodash@4.17.21

# With custom name
aws-lambda-layer zip --nodejs axios,lodash --name utility-layer

# With specific Node.js version
aws-lambda-layer zip --nodejs express@4.18.2 --node-version 20

# Scoped packages
aws-lambda-layer zip --nodejs @babel/core@7.23.0,@babel/types@7.23.0

Publish to AWS

# Basic publish
aws-lambda-layer publish --nodejs express@4.18.2 --description "Express layer"

# With custom layer name
aws-lambda-layer publish --nodejs date-fns,uuid --name utility-layer --description "Utility packages"

# Using specific AWS profile
aws-lambda-layer publish --nodejs express@4.18.2 --profile production --description "Express layer"

# Specify AWS region
aws-lambda-layer publish --nodejs axios --region ap-east-1 --description "Axios layer"

# With both profile and region
aws-lambda-layer publish --nodejs lodash --profile dev --region us-east-1 --description "Lodash layer"

Python Examples

Create Local Zip Files

# Single package with version
aws-lambda-layer zip --python numpy==1.26.0

# Multiple packages
aws-lambda-layer zip --python numpy==1.26.0,pandas==2.1.3,requests>=2.31.0

# With custom name
aws-lambda-layer zip --python requests,pytz --name web-utils

# With specific Python version
aws-lambda-layer zip --python numpy==1.26.0 --python-version 3.12

# Using pip instead of uv
aws-lambda-layer zip --python pandas==2.1.3 --no-uv

Publish to AWS

# Basic publish
aws-lambda-layer publish --python numpy==1.26.0 --description "NumPy layer"

# Multiple packages with description
aws-lambda-layer publish --python requests==2.31.0,pytz==2023.3 --description "Web utilities"

# Using specific AWS profile
aws-lambda-layer publish --python pandas==2.1.3 --profile production --description "Pandas layer"

# Specify AWS region
aws-lambda-layer publish --python numpy==1.26.0 --region us-west-2 --description "NumPy layer"

# With both profile and region
aws-lambda-layer publish --python scikit-learn --profile ml-account --region eu-west-1 --description "ML layer"

Package Version Formats

Node.js

• express@4.18.2 - Exact version
• axios - Latest version
• lodash@^4.17.0 - Compatible version
• @babel/core@7.23.0,@babel/types@7.23.0 - Multiple scoped packages

Python

• numpy==1.26.0 - Exact version
• pandas - Latest version
• requests>=2.31.0 - Minimum version
• pytz~=2023.3 - Compatible version

Publishing to AWS

Requirements

Before using the publish command, ensure you have:

1. AWS CLI installed and configured

   aws configure
   # or for specific profile
   aws configure --profile production
   

2. IAM Permissions: Your IAM user/role needs:

   • lambda:PublishLayerVersion
   • sts:GetCallerIdentity (for account verification)
   • iam:ListAccountAliases (optional, for account info)

3. Region Configuration: Either:

   • Set default region: aws configure set region us-east-1
   • Or use --region flag when publishing

4. zip command installed: Ensure the zip command is available on your system.

Confirmation Prompt

When publishing, you'll see:

1. AWS Account ID
2. AWS Profile (if specified)
3. Account Aliases (if available)
4. Target Region
5. Confirmation prompt: Do you want to proceed? [Y/n]:

Press Y (or Enter for default Yes) to proceed, or N to cancel.

Output

Zip Command

Creates a zip file in the current directory with format:

• Node.js: <package-name>-<version>-nodejs<node-version>.zip
• Python: <package-name>-<version>-python<python-version>.zip

Publish Command

• Uploads layer to AWS Lambda
• Returns Layer ARN
• Shows usage examples
• Provides command to attach to existing Lambda functions

Troubleshooting

Common Issues

1. AWS credentials not configured

   aws configure
   # or
   aws configure --profile your-profile
   

2. IAM permissions missing

   • Ensure your AWS credentials has lambda:PublishLayerVersion permission

3. Layer name already exists

   • Use --name option to specify a different name
   • Or delete the existing layer version

4. Zip file too large

   • AWS limit: 50MB for direct upload
   • Consider using fewer packages or S3 upload for larger layers

5. Region not configured

   • Use --region flag or configure default region:

   aws configure set region us-east-1
   

Shell Completion

Completions are installed for bash and zsh. Restart your shell or source the completion files:

# Bash
source /etc/bash_completion.d/aws-lambda-layer-completion.bash

# Zsh
source /usr/local/share/zsh/site-functions/_aws-lambda-layer

License

MIT License

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.