Merge pull request #18 from chris-qa-org/add-cloudfront-viewer-request-function

Add CloudFront viewer-request function

Author: Stretch96

README.md

@@ -26,6 +26,7 @@ Terraform module to host a static site generated by Publii
 |------|------|
 | [aws_cloudfront_distribution.frontend](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/cloudfront_distribution) | resource |
 | [aws_cloudfront_distribution.frontend_www_redirect](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/cloudfront_distribution) | resource |
+| [aws_cloudfront_function.frontend_viewer_request](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/cloudfront_function) | resource |
 | [aws_cloudfront_origin_access_identity.frontend](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/cloudfront_origin_access_identity) | resource |
 | [aws_cloudfront_origin_access_identity.frontend_www_redirect](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/cloudfront_origin_access_identity) | resource |
 | [aws_iam_policy.publii_s3_frontend](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/iam_policy) | resource |
@@ -58,6 +59,7 @@ Terraform module to host a static site generated by Publii
 | [aws_s3_bucket_website_configuration.frontend_www_redirect](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/s3_bucket_website_configuration) | resource |
 | [aws_wafv2_web_acl.cloudfront_waf](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/wafv2_web_acl) | resource |
 | [random_id.project](https://registry.terraform.io/providers/hashicorp/random/latest/docs/resources/id) | resource |
+| [template_file.cloudfront_frontend_viewer_request_function](https://registry.terraform.io/providers/hashicorp/template/latest/docs/data-sources/file) | data source |
 | [template_file.frontend_bucket_cloudfront_read](https://registry.terraform.io/providers/hashicorp/template/latest/docs/data-sources/file) | data source |
 | [template_file.frontend_bucket_enforce_tls_statement](https://registry.terraform.io/providers/hashicorp/template/latest/docs/data-sources/file) | data source |
 | [template_file.frontend_bucket_policy](https://registry.terraform.io/providers/hashicorp/template/latest/docs/data-sources/file) | data source |

cloudfront-frontend-viewer-request-function.tf

@@ -0,0 +1,11 @@
+data "template_file" "cloudfront_frontend_viewer_request_function" {
+  template = file("${path.module}/cloudfront-functions/viewer-request.js")
+}
+
+resource "aws_cloudfront_function" "frontend_viewer_request" {
+  name    = "frontend-viewer-request"
+  runtime = "cloudfront-js-1.0"
+  comment = "frontend viewer-request function"
+  publish = true
+  code    = data.template_file.cloudfront_frontend_viewer_request_function.rendered
+}

cloudfront-frontend.tf

@@ -38,6 +38,11 @@ resource "aws_cloudfront_distribution" "frontend" {
     compress    = true
 
     viewer_protocol_policy = "redirect-to-https"
+
+    function_association {
+      event_type   = "viewer-request"
+      function_arn = aws_cloudfront_function.frontend_viewer_request.arn
+    }
   }
 
   default_root_object = "index.html"

cloudfront-functions/viewer-request.js

@@ -0,0 +1,11 @@
+function handler(event) {
+  // default variables
+  var req = event.request;
+  var clientIp = event.viewer.ip;
+
+  // set true-client-ip header
+  req.headers['true-client-ip'] = {value: clientIp};
+
+  // return request
+  return req;
+}