Add variable for the DB migrate lambda path

This allows the path to be set to a specific location and committed or
cached, so that it is not recreated unnecessarily in an automation
context.

main.tf

@@ -27,6 +27,7 @@ module "metaflow-metadata-service" {
   database_name                    = module.metaflow-datastore.database_name
   database_password                = module.metaflow-datastore.database_password
   database_username                = module.metaflow-datastore.database_username
+  db_migrate_lambda_zip_file       = var.db_migrate_lambda_zip_file
   datastore_s3_bucket_kms_key_arn  = module.metaflow-datastore.datastore_s3_bucket_kms_key_arn
   enable_api_basic_auth            = var.metadata_service_enable_api_basic_auth
   enable_api_gateway               = var.metadata_service_enable_api_gateway

modules/metadata-service/locals.tf

@@ -22,7 +22,7 @@ locals {
   api_gateway_stage_name                  = "api"
   api_gateway_usage_plan_name             = "${var.resource_prefix}usage-plan${var.resource_suffix}"
 
-  db_migrate_lambda_zip_file   = "${path.module}/db_migrate_lambda.zip"
+  db_migrate_lambda_zip_file   = coalesce(var.db_migrate_lambda_zip_file, "${path.module}/db_migrate_lambda.zip")
   db_migrate_lambda_name       = "${var.resource_prefix}db_migrate${var.resource_suffix}"
   lambda_ecs_execute_role_name = "${var.resource_prefix}lambda_ecs_execute${var.resource_suffix}"
 

modules/metadata-service/variables.tf

@@ -37,6 +37,12 @@ variable "enable_api_gateway" {
   description = "Enable API Gateway for public metadata service endpoint"
 }
 
+variable "db_migrate_lambda_zip_file" {
+  type        = string
+  description = "Output path for the zip file containing the DB migrate lambda"
+  default     = null
+}
+
 variable "fargate_execution_role_arn" {
   type        = string
   description = "The IAM role that grants access to ECS and Batch services which we'll use as our Metadata Service API's execution_role for our Fargate instance"

variables.tf

@@ -10,6 +10,12 @@ variable "batch_type" {
   default     = "ec2"
 }
 
+variable "db_migrate_lambda_zip_file" {
+  type        = string
+  description = "Output path for the zip file containing the DB migrate lambda"
+  default     = null
+}
+
 variable "enable_custom_batch_container_registry" {
   type        = bool
   default     = false