[F] Track CTA downloads in analytics

[1aurend]

No description provided.

[scryptmouse]

One small performance change, but otherwise looks fine on the API side!

[scryptmouse]

I would like to put a small cache on this to prevent a count scan from being executed on a potentially large table on each request. You'd just wrap the interior of the method body like this:

def total_download_count
  Rails.cache.fetch("statistics/total_download_count", expires_in: 5.minutes) do
    Analytics::Event.where(name: DOWNLOAD_EVENT_NAMES).count
  end
end

[1aurend]

Makes sense. The whole request is also cached for longer:

  def show
    expires_in 3.hours, public: true
    render_single_resource Statistics.new,
                           serializer: ::V1::StatisticsSerializer,
                           location: "[:api, :v1, :statistics]"
  end

Should we adjust the 3 hour timeline at all? It seems reasonable for most cases, but if anyone is testing this on Edge, it's a long wait.

[scryptmouse]

Ope, was not aware of that. I would reduce it to 10 minutes. That only sets cache headers, which is easily bypassed by direct API access, but three hours seems excessive to me. We don't want these counts to run on every request, but a bunch every 10 minutes should be fine.

Given that in the request, I'd go ahead and ignore the rails.cache.fetch I advised above, since I wasn't looking at the whole class in context, really, and we'll improve the caching on this in another pass sometime in the future. Bigger scope than this, though.