discourse/lib/vary_header.rb

# frozen_string_literal: true

module VaryHeader
  def ensure_vary_header
    response.headers['Vary'] ||= 'Accept' if !params[:format]
  end
end
FIX: Include the Vary:Accept header on all Accept-based responses (#14647) By default, Rails only includes the Vary:Accept header in responses when the Accept: header is included in the request. This means that proxies/browsers may cache a response to a request with a missing Accept header, and then later serve that cached version for a request which does supply the Accept header. This can lead to some very unexpected behavior in browsers. This commit adds the Vary:Accept header for all requests, even if the Accept header is not present in the request. If a format parameter (e.g. `.json` suffix) is included in the path, then the Accept header is still omitted. (The format parameter takes precedence over any Accept: header, so the response is no longer varies based on the Accept header) 2021-10-25 19:53:50 +08:00			`# frozen_string_literal: true`

			`module VaryHeader`
			`def ensure_vary_header`
			`response.headers['Vary'] \|\|= 'Accept' if !params[:format]`
			`end`
			`end`