34 lines
749 B
Ruby
34 lines
749 B
Ruby
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# frozen_string_literal: true
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require "base_conversion"
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require "consensus"
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require "weighted_average"
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# Blends exchange rates from multiple providers into a single set. Rebases each provider to a common base,
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# filters outliers via cross-provider consensus, then computes a recency-weighted average.
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class Blender
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attr_reader :rates, :base
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def initialize(rates, base:)
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@rates = rates.map { |r| r.is_a?(Hash) ? r : r.to_hash }
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@base = base
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end
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def blend
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WeightedAverage.new(consensus.annotated).calculate
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end
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def outliers
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consensus.outliers
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end
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private
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def consensus
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@consensus ||= begin
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rebased_rates = BaseConversion.new(rates, base:).convert
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Consensus.new(rebased_rates)
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end
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end
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end
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