Touching the counter_cultured model

[giuseb]

It would be nice if updating the counters also set the model's updated_at field to the current time, in order to facilitate cache expiration.

Imagine a Category index page listing category names and product counts. These days, it is trivial to perform http caching and/or cache the view using a key that includes the most recent change to the categories.

# controller
fresh_when last_modified: @categories.maximum(:updated_at)

# haml view
- cache ['categories', @categories.maximum(:updated_at)] do
  = the view template

Now, if I add/remove a product or change a product's category, I also need to touch the affected categories, otherwise the category index will be stale. Normally, you would enforce this like so:

belongs_to :category, touch: true

HOWEVER, this is too general, as it will cause the cache to needlessly expire when, for example, I am only editing a product's name or other attribute.

Thus, ideally I would like to be able to say something like:

counter_culture :category, touch: true

Does this sound reasonable? I looked at the source, and I understand that you eventually call rails' update_counters AR method, so the fix would be a little more involved than I initially hoped...

Thanks!
Giuseppe

[magnusvk]

It does sound reasonable. Not trivially easy (because I use
update_counters) but not really that hard either. I'll try and get to it
soon, though no promises. Otherwise, you are always free to submit a pull
request. :)

Thanks for getting in touch,
-Magnus

On Sun, Sep 22, 2013 at 4:30 AM, Giuseppe notifications@github.com wrote:

It would be nice if updating the counters also set the model's updated_at
field to the current time, in order to facilitate cache expiration.

Imagine a Category index page listing category names and product counts.
These days, it is trivial to cache the action and/or the view using a key
that includes the most recent change to the categories.

Now, if I add/remove a product or change a product's category, I also need
to touch the affected categories, otherwise the category index will be
stale. Normally, you would enforce this like so:

belongs_to :category, touch: true

HOWEVER, this is too general, as it will cause the cache to needlessly
expire when, for example, I am only editing a product's name or other
attribute.

Thus, ideally I would like to be able to say something like:

counter_culture :category, touch: true

Does this sound reasonable? I looked at the source, and I understand that
you eventually call rails' update_counters AR method, so the fix would be
a little more involved than I initially hoped...

Thanks!
Giuseppe

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Reply to this email directly or view it on GitHubhttps://github.com//issues/25
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[giuseb]

I had forked the project in view of attempting a solution, but this merge is such a treat!
Thanks so much for your work,
Giuseppe