AWS Lambda node20.x Boostrap script

node20.x-bootstrap.sh

#!/bin/sh
# Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.

if [ -z "$NODE_PATH" ];
then
  nodejs_mods="/opt/nodejs/node_modules"
  nodejs20_mods="/opt/nodejs/node20/node_modules"
  runtime_mods="/var/runtime/node_modules"
  task="/var/runtime:/var/task"
  export NODE_PATH="$nodejs20_mods:$nodejs_mods:$runtime_mods:$task"
fi

if [ -n "$AWS_LAMBDA_FUNCTION_MEMORY_SIZE" ];
then
  # For V8 options, both '_' and '-' are supported
  # Ref: https://github.com/nodejs/node/pull/14093
  semi_space_str_und="--max_semi_space_size"
  old_space_str_und="--max_old_space_size"

  semi_space_str=${semi_space_str_und//[_]/-}
  old_space_str=${old_space_str_und//[_]/-}

  # Do not override customers' semi and old space size options if they specify them
  # with NODE_OPTIONS env var. If they just set one, use the default value from v8
  # for the other.
  case $NODE_OPTIONS in
  *$semi_space_str_und*);;
  *$old_space_str_und*);;
  *$semi_space_str*);;
  *$old_space_str*);;
  *)
    # New space should be 5% of AWS_LAMBDA_FUNCTION_MEMORY_SIZE, leaving 5% available for buffers, for instance,
    # very large images or JSON files, which are allocated as C memory, rather than JavaScript heap in V8.
    new_space=$(($AWS_LAMBDA_FUNCTION_MEMORY_SIZE / 10))
    # The young generation size of the V8 heap is three times the size of the semi-space,
    # an increase of 1 MiB to semi-space applies to each of the three individual semi-spaces
    # and causes the heap size to increase by 3 MiB.
    semi_space=$(($new_space / 6))
    # Old space should be 90% of AWS_LAMBDA_FUNCTION_MEMORY_SIZE
    old_space=$(($AWS_LAMBDA_FUNCTION_MEMORY_SIZE - $new_space))
    MEMORY_ARGS=(
      "$semi_space_str=$semi_space"
      "$old_space_str=$old_space"
    )
    ;;
  esac
fi

# If NODE_EXTRA_CA_CERTS is being set by the customer, don't override. Else, include RDS CA
if [ -z "${NODE_EXTRA_CA_CERTS+set}" ]; then
  # Use the default CA bundle in regions that have 3 dashes in their name
  if [ "${AWS_REGION:0:6}" != "us-gov" ] && [ "${AWS_REGION//[^-]}" == "---" ]; then
    export NODE_EXTRA_CA_CERTS=/etc/pki/tls/certs/ca-bundle.crt
  fi
fi

export AWS_EXECUTION_ENV=AWS_Lambda_nodejs20.x

NODE_ARGS=(
    --expose-gc
    --max-http-header-size 81920
    "${MEMORY_ARGS[@]}"
    /var/runtime/index.mjs
    )

if [ -z "$AWS_LAMBDA_EXEC_WRAPPER" ]; then
  exec /var/lang/bin/node "${NODE_ARGS[@]}"
else
  wrapper="$AWS_LAMBDA_EXEC_WRAPPER"
  if [ ! -f "$wrapper" ]; then
    echo "$wrapper: does not exist"
    exit 127
  fi
  if [ ! -x "$wrapper" ]; then
    echo "$wrapper: is not an executable"
    exit 126
  fi
    exec -- "$wrapper" /var/lang/bin/node "${NODE_ARGS[@]}"
fi