Google Cloud Storage example CORS configuration for Rails/ActiveStorage

README.md

This gist shows you how to configure a Google Cloud Storage bucket CORS for use with Rails' ActiveStorage (or any other direct-upload mechanism).

1. Update the policy JSON to reflect your setup (likely only changing the origin parameter)
2. Run this: $ gsutil cors set ./cors-json-file.json gs://<bucket-name>

cors.json

[
  {
    "origin": ["https://example.com"],
    "responseHeader": [
      "Content-Type",
      "Content-Md5",
      "Origin",
      "Content-Disposition"
    ],
    "method": [
      "PUT",
      "POST",
      "GET",
      "HEAD",
      "DELETE",
      "OPTIONS"
    ],
    "maxAgeSeconds": 3600
  }
]