Class: JsonapiCompliable::Scoping::Paginate

Inherits:
Base
  • Object
show all
Defined in:
lib/jsonapi_compliable/scoping/paginate.rb

Overview

Apply pagination logic to the scope

If the user requests a page size greater than MAX_PAGE_SIZE, a JsonapiCompliable::Errors::UnsupportedPageSize error will be raised.

Notably, this will not fire when the `default: false` option is passed. This is the case for sideloads - if the user requests “give me the post and its comments”, we shouldn't implicitly limit those comments to 20. BUT if the user requests, “give me the post and 3 of its comments”, we should honor that pagination.

This can be confusing because there are also 'default' and 'customized' pagination procs. The default comes 'for free'. Customized pagination looks like

class PostResource < ApplicationResource
  paginate do |scope, current_page, per_page|
    # ... the custom logic ...
  end
end

We should use the default unless the user has customized.

See Also:

Constant Summary

MAX_PAGE_SIZE = 
1_000

Instance Attribute Summary

Attributes inherited from Base

#query_hash, #resource

Instance Method Summary collapse

Methods inherited from Base

#initialize

Constructor Details

This class inherits a constructor from JsonapiCompliable::Scoping::Base

Instance Method Details

#apply ⇒ Object

Apply the pagination logic. Raise error if over the max page size.

Returns:

  • the scope object we are chaining/modifying



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# File 'lib/jsonapi_compliable/scoping/paginate.rb', line 30

def apply
  if size > MAX_PAGE_SIZE
    raise JsonapiCompliable::Errors::UnsupportedPageSize
      .new(size, MAX_PAGE_SIZE)
  else
    super
  end
end

#apply? ⇒ Boolean

We want to apply this logic unless we've explicitly received the default: false option. In that case, only apply if pagination was explicitly specified in the request.

Returns:

  • (Boolean) —

    should we apply this logic?



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# File 'lib/jsonapi_compliable/scoping/paginate.rb', line 44

def apply?
  if @opts[:default] == false
    not [page_param[:size], page_param[:number]].all?(&:nil?)
  else
    true
  end
end

#apply_custom_scope ⇒ Object

Apply the custom pagination proc



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# File 'lib/jsonapi_compliable/scoping/paginate.rb', line 63

def apply_custom_scope
  custom_scope.call(@scope, number, size)
end

#apply_standard_scope ⇒ Object

Apply default pagination proc via the Resource adapter



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# File 'lib/jsonapi_compliable/scoping/paginate.rb', line 58

def apply_standard_scope
  resource.adapter.paginate(@scope, number, size)
end

#custom_scope ⇒ Proc, Nil

Returns the custom pagination proc

Returns:

  • (Proc, Nil) —

    the custom pagination proc



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# File 'lib/jsonapi_compliable/scoping/paginate.rb', line 53

def custom_scope
  resource.pagination
end