Module: Blockchain0xX402::Server

Defined in:
lib/blockchain0x_x402/server.rb

Defined Under Namespace

Classes: PricingEntry, RackMiddleware, VerifyFailure, VerifyOk

Constant Summary collapse

CAIP2_BY_NETWORK = 
{
  'mainnet' => 'eip155:8453',
  'testnet' => 'eip155:84532',
}.freeze
PAYMENT_ENV_KEY = 
'blockchain0x.x402_payment'

Class Method Summary collapse

Class Method Details

.build_402_body(entry:, resource:, default_network:, max_age_seconds:) ⇒ Object

Render the canonical 402 body. Used internally by the middleware; exported for alternative adapters.



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# File 'lib/blockchain0x_x402/server.rb', line 96

def self.build_402_body(entry:, resource:, default_network:, max_age_seconds:)
  req = build_requirement(entry, default_network)
  req.max_age_seconds = max_age_seconds
  Wire::X402Response.new(version: 1, resource: resource, accepts: [req])
end

.build_requirement(entry, default_network) ⇒ Object

Build a PaymentRequirement struct from a pricing entry + network fallback. Exported so alternative adapters (Rails ActionController::API, Grape) can reuse it.



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# File 'lib/blockchain0x_x402/server.rb', line 81

def self.build_requirement(entry, default_network)
  network = entry.network || default_network || 'mainnet'
  Wire::PaymentRequirement.new(
    scheme: 'exact-usdc',
    network: network,
    chain_id: CAIP2_BY_NETWORK.fetch(network),
    pay_to_address: entry.pay_to_address,
    amount_wei_usdc: usdc_decimal_to_wei(entry.amount_usdc),
    payment_request_id: entry.payment_request_id,
    max_age_seconds: nil,
  )
end

.usdc_decimal_to_wei(decimal) ⇒ Object

Convert a human decimal USDC amount (“0.10”) to a 6-decimal wei integer string (“100000”). Mirrors the equivalent helper in @blockchain0x/x402’s shared.ts.



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# File 'lib/blockchain0x_x402/server.rb', line 70

def self.usdc_decimal_to_wei(decimal)
  whole, frac = decimal.split('.', 2)
  whole = '0' if whole.nil? || whole.empty?
  frac ||= ''
  frac = frac.ljust(6, '0')[0, 6]
  (whole.to_i * 1_000_000 + frac.to_i).to_s
end

.verify_x_payment(sdk:, header:, entry:) ⇒ Object 



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# File 'lib/blockchain0x_x402/server.rb', line 132

def self.verify_x_payment(sdk:, header:, entry:)
  if header.nil? || header.empty?
    return VerifyFailure.new('header_missing', 'X-Payment header is required.')
  end

  begin
    payment = Wire.parse_payment_header(header)
  rescue WireError => e
    return VerifyFailure.new('header_malformed', e.message)
  end

  if payment.payment_request_id != entry.payment_request_id
    return VerifyFailure.new(
      'requirement_mismatch',
      "X-Payment references #{payment.payment_request_id}, " \
        "route quoted #{entry.payment_request_id}.",
    )
  end

  begin
    sdk.payment_requests_settle(
      payment_request_id: payment.payment_request_id,
      body: {
        'txHash' => payment.tx_hash,
        'payerAddress' => payment.payer_address,
        'amountUsdcVerified' => payment.amount_usdc,
      },
    )
  rescue StandardError => e
    msg = e.message
    msg = 'settle() rejected the proof.' if msg.nil? || msg.empty?
    return VerifyFailure.new('settle_rejected', msg)
  end

  VerifyOk.new(payment)
end

.x402_response_to_hash(resp) ⇒ Object 



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# File 'lib/blockchain0x_x402/server.rb', line 102

def self.x402_response_to_hash(resp)
  {
    'version' => resp.version,
    'resource' => resp.resource,
    'accepts' => resp.accepts.map do |r|
      h = {
        'scheme' => r.scheme,
        'network' => r.network,
        'chainId' => r.chain_id,
        'payToAddress' => r.pay_to_address,
        'amountWeiUsdc' => r.amount_wei_usdc,
        'paymentRequestId' => r.payment_request_id,
      }
      h['maxAgeSeconds'] = r.max_age_seconds unless r.max_age_seconds.nil?
      h
    end,
  }
end