[NDR-54] Stopping Terraform overwriting Lambdas (#291)

* [NDR-54] Add lifecycle blocks to Lambda resources to ignore changes during CI/CD deployments

* [NDR-54] Add layers to ignore_changes in Lambda lifecycle to prevent unnecessary updates during CI/CD

* [NDR-54] Remove last_modified from ignore_changes in Lambda lifecycle to streamline CI/CD deployments

Author: MatthewMoore-NHS

infrastructure/modules/lambda/main.tf

@@ -20,6 +20,14 @@ resource "aws_lambda_function" "lambda" {
     "arn:aws:lambda:eu-west-2:580247275435:layer:LambdaInsightsExtension:53",
     "arn:aws:lambda:eu-west-2:282860088358:layer:AWS-AppConfig-Extension:120"
   ]
+
+  lifecycle {
+    ignore_changes = [
+      # These are required as Lambdas are deployed via the CI/CD pipelines
+      source_code_hash,
+      layers
+    ]
+  }
 }
 
 resource "aws_api_gateway_integration" "lambda_integration" {

infrastructure/modules/lambda_layers/main.tf

@@ -13,4 +13,11 @@ resource "aws_lambda_layer_version" "lambda_layer" {
   layer_name               = local.lambda_layer_aws_name
   compatible_runtimes      = ["python3.11"]
   compatible_architectures = ["x86_64"]
+
+  lifecycle {
+    ignore_changes = [
+      # These are required as Lambdas are deployed via the CI/CD pipelines
+      filename
+    ]
+  }
 }