Script for creating an AWS lambda layer for a python library/libraries

create-lambda-layer.sh

#!/usr/bin/env bash

# To run this script directly from this gist, run the following command. Make sure to replace
# the arguments with your desired arguments.
# 
# curl https://gist.githubusercontent.com/zmunk/2bc71b940d4a821b59ab073299de5f55/raw/create-lambda-layer.sh \
#   | bash -s python3.11 schematichq pydantic pydantic_core schematic-py311-lambda-layer

# Exit the script immediately if any command returns a non-zero (failure) exit code.
set -e

# Echo red bold text to stderr
function eecho { echo -e "\e[1;31m$@\e[0m" 1>&2; }

# check if aws cli is configured
if ! aws sts get-caller-identity >/dev/null ; then
  eecho "please configure aws cli"
  exit 1
fi

usage=$(cat << EOF
$0 python3.11 redis redis-py311-lambda-layer
$0 python3.11 schematichq pydantic pydantic_core schematic-py311-lambda-layer
$0 python3.11 pydantic pydantic-py311-lambda-layer -- --platform manylinux2014_x86_64 --only-binary=:all:
EOF
)

if [ -z "$1" ]; then
  eecho "please provide python version"
  eecho "e.g. '$usage'"
  exit 1
fi
python_version="$1"
shift

# Extract Pip Arguments (everything after --)
# and Script Arguments (libraries and target)
libraries_and_layer_name=()
pip_extra_args=()
is_pip_arg=false

for arg in "$@"; do
  if [[ "$arg" == "--" ]]; then
    is_pip_arg=true  # Everything after this is a pip flag
    continue
  fi
  if [ "$is_pip_arg" = true ]; then
    pip_extra_args+=("$arg")
  else
    libraries_and_layer_name+=("$arg")
  fi
done


if [ "${#libraries_and_layer_name[@]}" -lt 2 ]; then
  eecho "Error: Please provide library name(s) and a layer name."
  eecho "e.g. '$usage'"
  exit 1
fi

# Get last element
layer_name="${libraries_and_layer_name[-1]}"

# get all but last element
libraries=("${libraries_and_layer_name[@]:0:${#libraries_and_layer_name[@]}-1}")

cache=.aws_cache
layer_folder="$cache/lambda-layer"
site_packages="$layer_folder/python/lib/$python_version/site-packages"
zipfile=lambda-layer.zip

mkdir -p $site_packages

INSTALL_CMD=($python_version -m pip install $libraries -t $site_packages "${pip_extra_args[@]}")
"${INSTALL_CMD[@]}" # execute installation command

(cd $layer_folder && zip -r ../$zipfile *)

aws lambda publish-layer-version \
    --layer-name "$layer_name" \
    --description "$libraries lambda layer for $python_version" \
    --license-info "MIT" \
    --zip-file "fileb://$cache/$zipfile" \
    --compatible-runtimes "$python_version" \
    --query "LayerVersionArn" \
    --output text

rm -r $layer_folder
rm $cache/$zipfile