Class: Amazon::SalesRankMetrics

Inherits:
Object
  • Object
show all
Includes:
Service
Defined in:
app/services/amazon/sales_rank_metrics.rb

Overview

Builds the bounded sales-rank summary used by an Amazon retailer's Trends
tab. It selects the best current listing/category pairs first, then fetches
history only for those pairs; loading the dashboard therefore stays bounded
as the daily data-point table grows.

Defined Under Namespace

Classes: Result, Row

Constant Summary collapse

CURRENT_MAX_AGE = 
14.days
COMPARISON_DAYS = 
30
COMPARISON_TOLERANCE_DAYS = 
7

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from Service

#attributes_used, #build_result, call, #logger

Methods included from Service::Initializer

#initialize

Instance Attribute Details

#catalog ⇒ Object (readonly) 



55
 
# File 'app/services/amazon/sales_rank_metrics.rb', line 55

validates :catalog, presence: true

#days ⇒ Object (readonly) 



56
 
# File 'app/services/amazon/sales_rank_metrics.rb', line 56

validates :days, :limit, numericality: { only_integer: true, greater_than: 0 }

#limit ⇒ Object (readonly) 



56
 
# File 'app/services/amazon/sales_rank_metrics.rb', line 56

validates :days, :limit, numericality: { only_integer: true, greater_than: 0 }

Instance Method Details

#call ⇒ Result

Returns:

Raises:

  • (ArgumentError) 


59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
 
# File 'app/services/amazon/sales_rank_metrics.rb', line 59

def call
  raise ArgumentError, errors.full_messages.to_sentence unless valid?

  points = current_points
  return Result.new(rows: [], window_days: days) if points.empty?

  histories = histories_for(points)
  catalog_items = CatalogItem.includes(store_item: :item)
                             .where(id: points.map(&:catalog_item_id))
                             .index_by(&:id)
  browse_node_names = browse_node_names_for(points)

  rows = points.filter_map do |point|
    catalog_item = catalog_items[point.catalog_item_id]
    next unless catalog_item

    pair_history = histories.fetch(pair_key(point), [])
    category_name = category_name_for(point, browse_node_names)

    Row.new(
      catalog_item_id: catalog_item.id,
      item_id: catalog_item.item_id,
      sku: catalog_item.sku,
      asin: catalog_item.amazon_asin,
      amazon_url: catalog_item.amazon_product_url,
      category_kind: point.category_kind,
      category_id: point.product_category_id,
      category_name:,
      current_rank: point.rank,
      observed_on: point.observed_on,
      observed_at: point.observed_at,
      change_30_days: change_30_days(point, pair_history),
      points: pair_history.map { |history_point| [history_point.observed_on.iso8601, history_point.rank] }
    )
  end

  Result.new(rows:, window_days: days)
end