feat(x402): auth-capture unlock gate + fee revenue metrics

internal/monetizeapi/types.go

@@ -304,6 +304,7 @@ type ServiceOfferPayment struct {
 	// x402 payment scheme.
 	// +kubebuilder:default="exact"
 	// +kubebuilder:validation:Enum=exact
+	// TODO(auth-capture): regenerate CRD manifests + wire per-offer unlock config
 	Scheme string `json:"scheme,omitempty"`
 	// Chain identifier for payments (human-friendly). Reconciler resolves
 	// to CAIP-2 format (e.g., "base-sepolia" → "eip155:84532").

internal/x402/authcapture.go

@@ -0,0 +1,123 @@
+package x402
+
+import (
+	"fmt"
+	"math/big"
+	"time"
+
+	"github.com/ethereum/go-ethereum/common"
+	x402types "github.com/x402-foundation/x402/go/v2/types"
+)
+
+const (
+	defaultCaptureDeadlineSecs = 900
+	defaultRefundDeadlineSecs  = 1800
+)
+
+// AuthCaptureUnlockConfig configures the single offer whose SIWX session is
+// minted only after an auth-capture payment verifies and settles.
+type AuthCaptureUnlockConfig struct {
+	Enabled             bool   `yaml:"enabled"`
+	OfferPrefix         string `yaml:"offerPrefix"`
+	Price               string `yaml:"price"`
+	Network             string `yaml:"network"`
+	PayTo               string `yaml:"payTo"`
+	Asset               string `yaml:"asset"`
+	FeeRecipient        string `yaml:"feeRecipient"`
+	MinFeeBps           uint16 `yaml:"minFeeBps"`
+	MaxFeeBps           uint16 `yaml:"maxFeeBps"`
+	CaptureAuthorizer   string `yaml:"captureAuthorizer"`
+	CaptureDeadlineSecs uint64 `yaml:"captureDeadlineSecs"`
+	RefundDeadlineSecs  uint64 `yaml:"refundDeadlineSecs"`
+}
+
+// Validate applies deadline defaults and rejects unusable auth-capture
+// configuration before a payment is sent to the facilitator.
+func (c *AuthCaptureUnlockConfig) Validate() error {
+	if c == nil {
+		return fmt.Errorf("authCaptureUnlock config is nil")
+	}
+	if c.CaptureDeadlineSecs == 0 {
+		c.CaptureDeadlineSecs = defaultCaptureDeadlineSecs
+	}
+	if c.RefundDeadlineSecs == 0 {
+		c.RefundDeadlineSecs = defaultRefundDeadlineSecs
+	}
+
+	if c.Enabled {
+		if c.OfferPrefix == "" {
+			return fmt.Errorf("offerPrefix must be non-empty when enabled")
+		}
+		if c.FeeRecipient == "" {
+			return fmt.Errorf("feeRecipient must be non-empty when enabled")
+		}
+		if c.CaptureAuthorizer == "" {
+			return fmt.Errorf("captureAuthorizer must be non-empty when enabled")
+		}
+	}
+	if c.MinFeeBps > c.MaxFeeBps {
+		return fmt.Errorf("minFeeBps %d exceeds maxFeeBps %d", c.MinFeeBps, c.MaxFeeBps)
+	}
+	if c.MaxFeeBps > 10000 {
+		return fmt.Errorf("maxFeeBps %d exceeds 10000", c.MaxFeeBps)
+	}
+	if c.MaxFeeBps > 0 && !validNonZeroAddress(c.FeeRecipient) {
+		return fmt.Errorf("feeRecipient must be a valid non-zero 0x address when maxFeeBps is positive")
+	}
+	if !validNonZeroAddress(c.CaptureAuthorizer) {
+		return fmt.Errorf("captureAuthorizer must be a valid non-zero 0x address")
+	}
+	if c.CaptureDeadlineSecs <= 6 {
+		return fmt.Errorf("captureDeadlineSecs must be greater than 6, got %d", c.CaptureDeadlineSecs)
+	}
+	if c.RefundDeadlineSecs < c.CaptureDeadlineSecs {
+		return fmt.Errorf("refundDeadlineSecs %d is less than captureDeadlineSecs %d", c.RefundDeadlineSecs, c.CaptureDeadlineSecs)
+	}
+
+	price, _, err := new(big.Float).SetPrec(128).Parse(c.Price, 10)
+	if err != nil {
+		return fmt.Errorf("price %q is not a valid decimal: %w", c.Price, err)
+	}
+	if price == nil || price.Sign() <= 0 {
+		return fmt.Errorf("price must be a positive decimal, got %q", c.Price)
+	}
+
+	return nil
+}
+
+func validNonZeroAddress(address string) bool {
+	return common.IsHexAddress(address) && common.HexToAddress(address) != (common.Address{})
+}
+
+// BuildAuthCaptureRequirement builds the strict auth-capture wire shape
+// expected by the facilitator.
+func BuildAuthCaptureRequirement(chain ChainInfo, asset AssetInfo, c *AuthCaptureUnlockConfig, payTo string, now time.Time) (x402types.PaymentRequirements, error) {
+	if err := c.Validate(); err != nil {
+		return x402types.PaymentRequirements{}, fmt.Errorf("validate auth-capture config: %w", err)
+	}
+	atomicAmount, err := decimalToAtomic(c.Price, asset.Decimals)
+	if err != nil {
+		return x402types.PaymentRequirements{}, fmt.Errorf("invalid price %q: %w", c.Price, err)
+	}
+
+	return x402types.PaymentRequirements{
+		Scheme:            "auth-capture",
+		Network:           chain.CAIP2Network,
+		Asset:             asset.Address,
+		Amount:            atomicAmount,
+		PayTo:             payTo,
+		MaxTimeoutSeconds: int(ClampMaxTimeoutSeconds(int64(c.CaptureDeadlineSecs))),
+		Extra: map[string]interface{}{
+			"name":                asset.EIP712Name,
+			"version":             asset.EIP712Version,
+			"captureAuthorizer":   c.CaptureAuthorizer,
+			"captureDeadline":     now.Unix() + int64(c.CaptureDeadlineSecs),
+			"refundDeadline":      now.Unix() + int64(c.RefundDeadlineSecs),
+			"feeRecipient":        c.FeeRecipient,
+			"minFeeBps":           c.MinFeeBps,
+			"maxFeeBps":           c.MaxFeeBps,
+			"autoCapture":         true,
+			"assetTransferMethod": asset.TransferMethod,
+		},
+	}, nil
+}