Apache’s mod_dir has a DirectoryIndex option so that if you request a directory, it can return the index document for that directory. For example:
https://www.example.com/dir/ would return https://www.example.com/dir/index.html
The directive typically looks something like this:
DirectoryIndex index.html index.cgi index.pl index.php index.xhtml index.htm(It’s been many years since I’ve seen index.cgi and index.pl!)
When I recently converted a WordPress site to a static site and hosted it via AWS CloudFront backed by AWS S3 buckets, I found that directory indexes didn’t work. A request for https://www.example.com/dir/ would return a 403 Forbidden error.
StackOverflow to the rescue (and a question from 2015, no less): How do you set a default root object for subdirectories for a statically hosted website on Cloudfront? included several possible solutions.
The solution I liked best was to deploy a pre-built Lambda function that implements similar functionality: standard-redirects-for-cloudfront.
Note that the instructions guide you to get the ARN from the CloudFormation output panel. This is important, as it is not just the ARN but also an appended version number. (In my case it was the ARN followed by :1.) Otherwise you’ll get the following error when adding it to the Origin request section of the CloudFormation behavior:
The function ARN must reference a specific function version. (The ARN must end with the version number.)