[WIP] add more logging for header validation

packages/app/server/src/env.ts

@@ -12,7 +12,7 @@ export const env = createEnv({
     // Server
     PORT: z.coerce.number().default(3069),
     NODE_ENV: z
-      .enum(['development', 'production', 'staging', "test"])
+      .enum(['development', 'production', 'staging', 'test'])
       .default('development'),
 
     // Network & Blockchain
@@ -50,8 +50,12 @@ export const env = createEnv({
     GOOGLE_SERVICE_ACCOUNT_KEY_ENCODED: z.string().optional(),
 
     // API Keys - Echo
-    API_KEY_HASH_SECRET: z.string().default('change-this-in-production-very-secret-key'),
-    API_ECHO_ACCESS_JWT_SECRET: z.string().default('api-jwt-secret-change-in-production'),
+    API_KEY_HASH_SECRET: z
+      .string()
+      .default('change-this-in-production-very-secret-key'),
+    API_ECHO_ACCESS_JWT_SECRET: z
+      .string()
+      .default('api-jwt-secret-change-in-production'),
 
     // Echo Configuration
     ECHO_MARKUP: z.string().default('1.25'),

packages/app/server/src/handlers/settle.ts

@@ -42,6 +42,12 @@ export async function settle(
   try {
     xPaymentData = validateXPaymentHeader(headers, req);
   } catch (error) {
+    logger.error('Payment header validation failed in settle', {
+      error: error instanceof Error ? error.message : String(error),
+      stack: error instanceof Error ? error.stack : undefined,
+      url: req.url,
+      method: req.method,
+    });
     buildX402Response(req, res, maxCost);
     return undefined;
   }
@@ -92,6 +98,19 @@ export async function settle(
   const settleResult = await facilitatorClient.settle(settleRequest);
 
   if (!settleResult.success || !settleResult.transaction) {
+    logger.error('Payment settlement failed', {
+      errorReason: settleResult.errorReason,
+      payer: settleResult.payer,
+      paymentAmount: paymentAmount,
+      nonce: payload.authorization.nonce,
+      signature: payload.signature.substring(0, 20) + '...', // Log first 20 chars for debugging
+      from: payload.authorization.from,
+      to: payload.authorization.to,
+      validAfter: payload.authorization.validAfter,
+      validBefore: payload.authorization.validBefore,
+      url: req.url,
+      method: req.method,
+    });
     buildX402Response(req, res, maxCost);
     return undefined;
   }

packages/app/server/src/services/facilitator/facilitatorProxy.ts

@@ -4,6 +4,7 @@ import {
   PaymentRequirements,
   SettleResponse,
   VerifyResponse,
+  ExactEvmPayload,
 } from './x402-types';
 import logger, { logMetric } from '../../logger';
 import dotenv from 'dotenv';
@@ -64,12 +65,10 @@ export async function facilitatorProxy<
   payload: PaymentPayload,
   paymentRequirements: PaymentRequirements
 ): Promise<T> {
-
   if (!PROXY_FACILITATOR_URL) {
     throw new Error('PROXY_FACILITATOR_URL is not set');
   }
 
-
   logMetric('facilitator_proxy_attempt', 1, {
     method,
   });
@@ -96,6 +95,59 @@ export async function facilitatorProxy<
   );
 
   if (res.status !== 200) {
+    let errorBody: string | undefined;
+    try {
+      errorBody = await res.text();
+    } catch (e) {
+      // Ignore errors reading response body
+    }
+
+    // Extract payment details for logging
+    const paymentDetails: Record<string, any> = {
+      scheme: payload.scheme,
+      network: payload.network,
+      x402Version: payload.x402Version,
+    };
+
+    // Extract signature and nonce if it's an ExactEvmPayload
+    if (
+      'payload' in payload &&
+      payload.payload &&
+      typeof payload.payload === 'object'
+    ) {
+      const evmPayload = payload.payload as ExactEvmPayload;
+      if (
+        'signature' in evmPayload &&
+        typeof evmPayload.signature === 'string'
+      ) {
+        paymentDetails.signature =
+          evmPayload.signature.substring(0, 20) + '...';
+      }
+      if (
+        'authorization' in evmPayload &&
+        evmPayload.authorization &&
+        typeof evmPayload.authorization === 'object'
+      ) {
+        if ('nonce' in evmPayload.authorization) {
+          paymentDetails.nonce = evmPayload.authorization.nonce;
+        }
+        if ('from' in evmPayload.authorization) {
+          paymentDetails.from = evmPayload.authorization.from;
+        }
+        if ('to' in evmPayload.authorization) {
+          paymentDetails.to = evmPayload.authorization.to;
+        }
+      }
+    }
+
+    logger.error('Facilitator proxy returned non-200 status', {
+      method,
+      status: res.status,
+      statusText: res.statusText,
+      errorBody: errorBody?.substring(0, 1000), // Limit to first 1000 chars
+      paymentPayload: paymentDetails,
+    });
+
     logMetric('facilitator_proxy_failure', 1, {
       method,
       status: res.status,

packages/app/server/src/types.ts

@@ -163,7 +163,7 @@ type TokenAmount = string;
 type Url = string;
 type Nonce = string;
 
-interface ExactEvmPayloadAuthorization {
+export interface ExactEvmPayloadAuthorization {
   from: Address;
   to: Address;
   value: TokenAmount;