From e4f42581e694797e4528e0dd6f420b0374b12dff Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jonas=20Birm=C3=A9?= <jonas.birme@eyevinn.se>
Date: Wed, 10 Apr 2024 21:35:23 +0200
Subject: [PATCH] chore: cloudfront-function for url-rewrite needed for SPA

---
 aws/cloudfront-functions/README.md            | 13 +++++++
 aws/cloudfront-functions/url-rewrite-spa.yaml | 39 +++++++++++++++++++
 2 files changed, 52 insertions(+)
 create mode 100644 aws/cloudfront-functions/README.md
 create mode 100644 aws/cloudfront-functions/url-rewrite-spa.yaml

diff --git a/aws/cloudfront-functions/README.md b/aws/cloudfront-functions/README.md
new file mode 100644
index 00000000..179439a6
--- /dev/null
+++ b/aws/cloudfront-functions/README.md
@@ -0,0 +1,13 @@
+# URL rewrite for single page applications (SPAs)
+
+CloudFront Functions event type: viewer request
+
+## Creating the function
+
+```
+aws cloudformation deploy \
+  --region us-east-1 \
+  --stack-name url-rewrite-stack \
+  --template-file ./url-rewrite-spa.yaml \
+  --parameter-overrides AutoPublishParam=true
+```
diff --git a/aws/cloudfront-functions/url-rewrite-spa.yaml b/aws/cloudfront-functions/url-rewrite-spa.yaml
new file mode 100644
index 00000000..08d6cb81
--- /dev/null
+++ b/aws/cloudfront-functions/url-rewrite-spa.yaml
@@ -0,0 +1,39 @@
+AWSTemplateFormatVersion: 2010-09-09
+Description: URL rewrite for React Router SPA with client-side routing
+
+Parameters:
+  AutoPublishParam:
+    Description: Whether to automatically publish on creation
+    Type: String
+    Default: false
+    AllowedValues:
+      - true
+      - false
+
+Resources:
+  RewriteFunction:
+    Type: AWS::CloudFront::Function
+    Properties:
+      AutoPublish: !Ref AutoPublishParam
+      FunctionCode: !Sub |
+        function handler(event) {
+          var request = event.request;
+          var uri = request.uri;
+          var paths = ['assets/', 'img/', '.xml', '.webmanifest', '.js', 'robots.txt']
+          var isServerPath = (path) => uri.includes(path);
+
+          if (!paths.some(isServerPath)) {
+            request.uri = '/';
+          }
+
+          return request;
+        }
+      FunctionConfig:
+        Comment: "Rewrite the URL for SPAs with client-side routing"
+        Runtime: cloudfront-js-1.0
+      Name: !Sub "${AWS::StackName}-rewriteFunction"
+
+Outputs:
+  FunctionArn:
+    Description: CloudFront Function
+    Value: !GetAtt RewriteFunction.FunctionMetadata.FunctionARN