A Rails gem providing FIFO (First In, First Out) and LIFO (Last In, First Out) inventory calculation methods for ActiveRecord models.

Add this line to your application's Gemfile:

gem "acts_as_fifo_lifo"

And then execute:

$ bundle

Or install it yourself as:

$ gem install acts_as_fifo_lifo

Include the module in your ActiveRecord model and configure the field mappings:

class StockTransaction < ApplicationRecord
  acts_as_fifo_lifo item_field: :item_id,
    qty_field: :quantity,
    cost_field: :unit_cost,
    time_field: :created_at,
    batch_field: :batch_number,
    storage_field: :storage_id,
    operation_field: :operation_id,
    operation_type_field: :operation_type

end

FIFO LIFO Warehouse Application

Returns an ordered list of batches needed to satisfy a quantity request.

StockTransaction.get_batches_for(1, 1, 100, Time.current, method: "fifo")
# => [{ batch_number: "B001", qty: 50, cost: 10.5, batch_time: 2024-01-01 10:00:00 }, ...]

Returns stock balance grouped by storage, item, and batch in a nested structure.

Returns stock balance grouped by storage and item with mean cost calculation.

Returns stock movement with running balance, grouped by storage, item, and transaction.

Returns an ActiveRecord::Relation with aggregate stock data per item (total_qty and mean_cost).

Transforms item stock balance records into a structured array format.

Contribution directions go here.

The gem is available as open source under the terms of the MIT License.