Usage

Use .before, .after, or .cursor in ActiveRecord queries to paginate data. A default limit is always applied, or you can override by including .limit in your request.

For example, say we have an app with User and Post models.

# app/models/user.rb
class User < ActiveRecord::Base
  has_many :posts
end

# app/models/post.rb
class Post < ActiveRecord::Base
  belongs_to :user
end

We can retrieve posts starting with the most recent

Post.before                 # get the first page of most recent posts with the default limit
Post.before.limit(10)       # get the 10 most recent posts
Post.before(999).limit(10)  # get the 10 most recent posts that were created before the post with id=999
Post.where(user: User.first).before(999)  # get the 10 most recent posts meeting a condition
User.first.posts.before     # get the most recent posts belong to a user

Likewise, we can results starting from the oldest records

Post.after                  # get the first page of oldest posts with the default limit
Post.after.limit(10)        # get the 10 oldest posts
Post.after(999).limit(10)   # get the 10 oldest posts that are newer than the post with id=999
Post.where(user: User.first).after(999)  # get the 10 oldest posts meeting a condition
User.first.posts.after      # get the oldest posts belong to a user

Sorting results

By default, all results are returned in ascending order.

To customize, set a config option, class option or per-query option

Adding pagination metadata to responses

This gem makes no assumptions about how you want to return pagination metadata in your responses. Arrays and results provide the cursor information you need.

result = Post.before(999)
result.length
 => 20
result.cursor_before
 => 990  # the minimum id included in the result
result.cursor_after
 => 998  # the maximum id included in the result

TODO

• option for sorting results
• cursor methods on array
• global default for limits
• per-model setting for limits