https://github.com/academia-edu/cached_counts

A replacement for Rails' counter caches, using memcached
https://github.com/academia-edu/cached_counts

Last synced: about 2 months ago
JSON representation

A replacement for Rails' counter caches, using memcached

• Host: GitHub
• URL: https://github.com/academia-edu/cached_counts
• Owner: academia-edu
• License: mit
• Created: 2016-05-08T17:59:05.000Z (over 8 years ago)
• Default Branch: master
• Last Pushed: 2022-07-14T14:58:48.000Z (about 2 years ago)
• Last Synced: 2024-07-12T14:45:45.127Z (2 months ago)
• Language: Ruby
• Size: 367 KB
• Stars: 3
• Watchers: 32
• Forks: 3
• Open Issues: 2
• Metadata Files:
  • Readme: README.rdoc
  • License: MIT-LICENSE

Awesome Lists containing this project

README

        
= CachedCounts

{}[https://circleci.com/gh/academia-edu/cached_counts]

A replacement for Rails' counter caches, using memcached.

Caches counts of models in a scope or association in memcached, and keeps the

cache up to date using incr/decr operations.

You might prefer this gem over Rails' built-in counter caches when:

* You want to cache the total number of models for a class or scope

* You have a large association (e.g. followers of a popular figure) and want to avoid contention on a database row

* You want your caches to occasionally expire and be refreshed to mitigate the risk of getting out of sync

* You don't need to use counts as part of more complex SQL queries

There are {many alternatives}[https://rubygems.org/search?utf8=%E2%9C%93&query=counter+cache], but this gem appears to be unique in its approach. Other gems solve the contention issue by pushing updates to a background job, which has the advantage of continuing to populate a column that can be queried via SQL, but is still more costly than our approach, while introducing a synchronization delay.

= Usage

{Documentation}[http://academia-edu.github.io/cached_counts/]

Basic usage:

  class User < ActiveRecord::Base

    include CachedCounts

    has_many :followers, class_name: 'Following' #, ...

    scope :confirmed, ->{ where(confirmed: true) }

    # creates cached class method `User.confirmed_count`

    caches_count_where :confirmed, if: :confirmed?

    # creates cached instance method `user.followers_count`

    caches_count_of :followers

  end

  class Following < ActiveRecord::Base

    include CachedCounts

    belongs_to :followee, class_name: 'User' #, ...

  end

Note that +CachedCounts+ must be included in the counted class, but no class methods need be called there.

For full options, see docs for +CachedCounts.caches_count_of+ and +CachedCounts.caches_count_where+.

= Licence

MIT

Copyright Academia.edu

= Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/academia-edu/cached_counts