Module: ZeroClick::Sellers::Stateful::Money

Defined in:
lib/zeroclick/sellers/stateful/money.rb

Overview

Micro-USD codec for the stateful wire's money strings.

Constant Summary collapse

MICROS_PER_USD = 
1_000_000
MAX_SAFE_MICROS =

Every SDK enforces the same ceiling — 2^53 - 1 — regardless of native integer width, so a value one SDK accepts can never overflow another. Ruby's Integer is arbitrary precision, so this is a contract rule here rather than a language limit: without it Ruby would happily accept amounts the TypeScript SDK cannot represent.

9_007_199_254_740_991
MONEY_RE =

Exactly six fraction digits, no sign, no exponent. The wire format is a fixed-point decimal string precisely so no SDK has to agree with another about float rounding.

/\A\d+\.\d{6}\z/

Class Method Summary collapse

Class Method Details

.format_money_usd(micros) ⇒ Object 



41
42
43
44
45
46
47
48
 
# File 'lib/zeroclick/sellers/stateful/money.rb', line 41

def format_money_usd(micros)
  unless micros.is_a?(Integer) && !micros.is_a?(TrueClass) && micros >= 0 && micros <= MAX_SAFE_MICROS
    raise Error.new("malformed_input", operation: "format_money_usd",
                                       message: "micro-USD must be a non-negative integer within 2^53 - 1")
  end

  format("%d.%06d", micros / MICROS_PER_USD, micros % MICROS_PER_USD)
end

.money_usd?(value) ⇒ Boolean

Returns:

  • (Boolean) 


26
27
28
 
# File 'lib/zeroclick/sellers/stateful/money.rb', line 26

def money_usd?(value)
  value.is_a?(String) && MONEY_RE.match?(value)
end

.parse_money_usd(value) ⇒ Object

Returns micro-USD, or nil when the value is not a well-formed money string or exceeds the shared ceiling. nil rather than an exception: a malformed amount arrives from the wire, so it is an expected input.



33
34
35
36
37
38
39
 
# File 'lib/zeroclick/sellers/stateful/money.rb', line 33

def parse_money_usd(value)
  return nil unless money_usd?(value)

  whole, fraction = value.split(".")
  micros = (whole.to_i * MICROS_PER_USD) + fraction.to_i
  micros <= MAX_SAFE_MICROS ? micros : nil
end