Package Lambda

main.tf

data "external" "packaged_lambda" {
    program = concat(["${path.module}/files/package_lambda.sh", var.source_folder], var.exclude_files)
}

outputs.tf

output "filename" {
    value = data.external.packaged_lambda.result.filename
}

output "checksum" {
    value = data.external.packaged_lambda.result.checksum
}

package_lambda.sh

#!/usr/bin/env bash

set -eo pipefail

source_folder=$1
exclude_files=${@:2}
files=$(find $source_folder -type f)

declare -a included_files

while read -r line; do
    relative_path=$(realpath --relative-to="${source_folder}" "$line")

    include=1
    for exclude_path in ${exclude_files[@]}; do
        if [[ $relative_path == $exclude_path* ]]; then
            include=0
        fi
    done


    if [[ include -eq 1 ]]; then
        included_files+=($relative_path)
    fi
done <<< "$files"

pushd $PWD > /dev/null
cd ${source_folder}

checksums=""
for file in ${included_files[@]}; do
    checksums+=$(sha256sum ${file} | cut -d ' ' -f1)
done

final_checksum=$(echo $checksums | sha256sum | cut -d ' ' -f1)
lambda_name=$(basename $source_folder)
package_name="/tmp/${lambda_name}-${final_checksum}.zip"
rm -f $package_name

file_string=$(IFS=' '; echo "${included_files[@]}")

zip -r -q $package_name $file_string
popd > /dev/null

echo "{ \"filename\": \"${package_name}\", \"checksum\": \"${final_checksum}\" }"

root.tf

module "packaged_lambda" {
    source        = "../packaged_lambda"
    source_folder = var.source_folder
    exclude_files = var.exclude_files
}

variables.tf

variable "source_folder" {
  type = string
}

variable "exclude_files" {
  type = list(string)
}