HTTP no-cache access to S3 versioned objects

Question

I'm surprised I haven't seen this issue online.

Currently I have an S3 bucket that is served through Cloudfront on a custom domain.
e.g. An S3 bucket object is retrievable publicly via `https://cdn.mywebsite.com/picture.jpeg`.

The cloudfront distribution connects with the origin (S3) through an OAC, and the policy was applied to the bucket correctly.

I am able to retrieve all objects today, however there is some invisible caching and I'm unsure how to get around it.

For example, I can reach and retrieve `https://cdn.mywebsite.com/picture.jpeg` without issues.
Then, when I go to retrieve `https://cdn.mywebsite.com/picture.jpeg?versionId=....`, I get the same response as the prior call. It's cached.

How can I retrieve `https://cdn.mywebsite.com/picture.jpeg?versionId=....` without caching?

Here's what I've tried:
- Under my origin behavior, I have used the `CachingDisabled` policy under "Cache key and origin requests". This does indeed disable caching, but that policy doesn't forward query string arguments, so `picture.jpeg` and `picture.jpeg?versionId=...` are retrieved equivalently.
- I have tried creating an identical cache policy as `CachingDisabled`, with `Query strings - All` set for the cache key settings. As a result, I get a 403 error.

My interpretation is that when a request is sent via cdn.myexample.com/picture.jpeg?versionId=..., that version query string is stripped off before going to the S3 bucket. Hence, it doesn't cache picture.jpeg, but it's not retrieving the right image anymore.

Accepted Answer

Hey all, I fixed it. Since this had me pulling my hair out, here was my solution:

- On the Cloudfront distribution, Edit the Behavior for the S3 Cloudfront bucket.
- Find `Cache key and origin requests` and edit this so Headers includes the `Origin`, and set Query strings to `All`.

Finally, this is an important step. On the S3 bucket, you must give access to the Cloudfront distribution to get version tagging. I haven't narrowed down exactly which action solved it for me, but here's what worked:

```
{
    "Version": "2008-10-17",
    "Id": "PolicyForCloudFrontPrivateContent",
    "Statement": [
        {
            "Sid": "AllowCloudFrontServicePrincipal",
            "Effect": "Allow",
            "Principal": {
                "Service": "cloudfront.amazonaws.com"
            },
            "Action": [
                "s3:GetObject",
                "s3:GetObjectVersionTagging",
                "s3:GetObjectVersion"
            ],
            "Resource": "arn:aws:s3:::.... my bucket",
            "Condition": {
                "StringEquals": {
                    "AWS:SourceArn": "arn:aws:cloudfront::..... my distribution"
                }
            }
        },
        {
            "Sid": "Statement1",
            "Effect": "Allow",
            "Principal": {
                "Service": "cloudfront.amazonaws.com"
            },
            "Action": [
                "s3:ListBucket",
                "s3:ListBucketVersions"
            ],
            "Resource": "arn:aws:s3:::.... my bucket",
            "Condition": {
                "StringEquals": {
                    "AWS:SourceArn": "arn:aws:cloudfront::..... my distribution"
                }
            }
        }
    ]
}
```

HTTP no-cache access to S3 versioned objects

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