Class: Export::FileGrouper

Inherits:
Object
  • Object
show all
Defined in:
lib/export/file_grouper.rb

Instance Method Summary collapse

Instance Method Details

#build_group_map(groups:, id_extractor:) ⇒ Hash

Builds a map from item ID to group index (0-based).

Parameters:

  • groups (Array<Array>) —

    grouped items

  • id_extractor (Proc) —

    callable that returns ID for an item

Returns:

  • (Hash) —

    mapping of item ID to group index



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# File 'lib/export/file_grouper.rb', line 53

def build_group_map(groups:, id_extractor:)
  group_map = {}

  groups.each_with_index do |group, index|
    group.each do |item|
      group_map[id_extractor.call(item)] = index
    end
  end

  group_map
end

#group(items:, max_bytes:, size_extractor:) ⇒ Array<Array>

Groups items into batches that don’t exceed max_bytes.

Items larger than max_bytes will be placed in their own group. Order of items is preserved.

Parameters:

  • items (Array) —

    items to group

  • max_bytes (Integer) —

    maximum bytes per group

  • size_extractor (Proc) —

    callable that returns size in bytes for an item

Returns:

  • (Array<Array>) —

    array of groups, each group is an array of items



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# File 'lib/export/file_grouper.rb', line 26

def group(items:, max_bytes:, size_extractor:)
  groups = []
  current_group = []
  current_size = 0

  items.each do |item|
    size = size_extractor.call(item)

    if current_group.any? && (current_size + size > max_bytes)
      groups << current_group
      current_group = []
      current_size = 0
    end

    current_group << item
    current_size += size
  end

  groups << current_group if current_group.any?
  groups
end