Fix upstream transport fallback and connection timing

CHANGELOG.md

@@ -9,6 +9,13 @@ Release tags use the form `vX.Y.Z` and match `package.json`. GitHub Releases car
 
 ## [Unreleased]
 
+## [0.5.12] - 2026-08-12
+
+### Fixed
+
+- Proxy-generated HTTP 502/503/504 connection-reset responses now use the same retry, no-lock, and route-fallback behavior as thrown socket failures.
+- Outbound connections now allow five seconds per resolved address instead of Node's 250-millisecond default, preventing healthy but moderately latent TCP handshakes from being misreported as `ETIMEDOUT` across every ChatGPT address.
+
 ## [0.5.11] - 2026-08-12
 
 ### Fixed

package.json

@@ -1,7 +1,7 @@
 {
   "name": "@gitcommit90/rerouted",
   "productName": "ReRouted",
-  "version": "0.5.11",
+  "version": "0.5.12",
   "description": "A local AI router for connected accounts, models, named routes, and automatic fallback.",
   "author": "gitcommit90",
   "license": "MIT",

src/cli/index.js

@@ -3,11 +3,14 @@
 
 const fs = require("node:fs");
 const path = require("node:path");
+const { configureNetworkDefaults } = require("../lib/network");
 const { createHeadlessRuntime, createProcessLock, defaultUserData } = require("../lib/headless-runtime");
 const { createPrompts } = require("./prompts");
 const { runFirstSetup } = require("./setup");
 const packageJson = require("../../package.json");
 
+configureNetworkDefaults();
+
 const HELP = `ReRouted ${packageJson.version}
 
 Usage:

src/lib/network.js

@@ -0,0 +1,30 @@
+"use strict";
+
+const net = require("node:net");
+
+// Node's 250 ms default is too short for otherwise healthy TCP paths and can
+// exhaust every resolved address before TLS has a chance to start. Keep
+// dual-stack address fallback, but give each connection attempt a realistic
+// window.
+const ADDRESS_ATTEMPT_TIMEOUT_MS = 5_000;
+
+function configureNetworkDefaults(network = net) {
+  if (typeof network.setDefaultAutoSelectFamily === "function") {
+    network.setDefaultAutoSelectFamily(true);
+  }
+  if (typeof network.setDefaultAutoSelectFamilyAttemptTimeout === "function") {
+    network.setDefaultAutoSelectFamilyAttemptTimeout(ADDRESS_ATTEMPT_TIMEOUT_MS);
+  }
+  return {
+    autoSelectFamily:
+      typeof network.getDefaultAutoSelectFamily === "function"
+        ? network.getDefaultAutoSelectFamily()
+        : null,
+    attemptTimeoutMs:
+      typeof network.getDefaultAutoSelectFamilyAttemptTimeout === "function"
+        ? network.getDefaultAutoSelectFamilyAttemptTimeout()
+        : null,
+  };
+}
+
+module.exports = { ADDRESS_ATTEMPT_TIMEOUT_MS, configureNetworkDefaults };

src/lib/router.js

@@ -274,6 +274,14 @@ function classifyFailure(status, errorText) {
       text
     );
   if (request) return { eligible: false, kind: "request", defaultCooldownMs: 0 };
+  const transportResponse =
+    [502, 503, 504].includes(Number(status)) &&
+    /upstream connect error|disconnect\/reset before headers|reset reason:\s*(?:connection|remote)|connection (?:termination|reset|refused)|socket hang up|tls (?:handshake|connection)|(?:dns|name) resolution|no healthy upstream|upstream (?:request )?timeout|gateway timeout/.test(
+      text
+    );
+  if (transportResponse) {
+    return { eligible: false, kind: "transport", defaultCooldownMs: 0 };
+  }
   const capability =
     (status === 400 || status === 404 || status === 422) &&
     (/(?:unsupported|invalid|unknown)[ _-]?model|model[ _-]?(?:not[ _-]?found|unsupported|unavailable)/.test(
@@ -751,15 +759,17 @@ function isAbortError(err) {
 function transportErrorMessage(error) {
   const parts = [];
   const seen = new Set();
-  let current = error;
-  for (let depth = 0; current && depth < 4; depth += 1) {
-    if (seen.has(current)) break;
+  const pending = [error];
+  for (let inspected = 0; pending.length && inspected < 12; inspected += 1) {
+    const current = pending.shift();
+    if (!current || seen.has(current)) continue;
     seen.add(current);
     const code = typeof current.code === "string" ? current.code.trim() : "";
     const message = String(current.message || current).trim();
     const detail = code && !message.includes(code) ? `${code}: ${message}` : message;
     if (detail && !parts.includes(detail)) parts.push(detail);
-    current = current.cause;
+    if (current.cause) pending.push(current.cause);
+    if (Array.isArray(current.errors)) pending.push(...current.errors);
   }
   return parts.join("; ") || "Upstream connection failed";
 }
@@ -1014,6 +1024,7 @@ function createRouter({
             failureKind: classification.kind,
             defaultCooldownMs: classification.defaultCooldownMs,
             resetAt: inspected.failure.resetAt,
+            transportError: classification.kind === "transport",
           };
         }
         if (inspected.openAiJson) {
@@ -1076,6 +1087,7 @@ function createRouter({
           failureKind: classification.kind,
           defaultCooldownMs: classification.defaultCooldownMs,
           resetAt: parseResetHint(res, text),
+          transportError: classification.kind === "transport",
         };
       }
 
@@ -1186,6 +1198,7 @@ function createRouter({
           failureKind: classification.kind,
           defaultCooldownMs: classification.defaultCooldownMs,
           resetAt: parseResetHint(res, JSON.stringify(raw)),
+          transportError: classification.kind === "transport",
         };
       }
       let openAiJson = raw;

src/main.js

@@ -2,6 +2,7 @@
 
 const path = require("node:path");
 const fs = require("node:fs");
+const { configureNetworkDefaults } = require("./lib/network");
 const {
   app,
   BrowserWindow,
@@ -16,6 +17,8 @@ const {
   powerMonitor,
 } = require("electron");
 
+configureNetworkDefaults();
+
 const { createStore } = require("./lib/store");
 const { createRouter } = require("./lib/router");
 const { createGateway } = require("./lib/gateway");

tests/network.test.js

@@ -0,0 +1,35 @@
+"use strict";
+
+const { describe, it } = require("node:test");
+const assert = require("node:assert/strict");
+
+const {
+  ADDRESS_ATTEMPT_TIMEOUT_MS,
+  configureNetworkDefaults,
+} = require("../src/lib/network");
+
+describe("network defaults", () => {
+  it("keeps address-family fallback and replaces Node's 250 ms connection window", () => {
+    const state = { autoSelectFamily: false, attemptTimeoutMs: 250 };
+    const network = {
+      setDefaultAutoSelectFamily(value) {
+        state.autoSelectFamily = value;
+      },
+      getDefaultAutoSelectFamily() {
+        return state.autoSelectFamily;
+      },
+      setDefaultAutoSelectFamilyAttemptTimeout(value) {
+        state.attemptTimeoutMs = value;
+      },
+      getDefaultAutoSelectFamilyAttemptTimeout() {
+        return state.attemptTimeoutMs;
+      },
+    };
+
+    assert.deepEqual(configureNetworkDefaults(network), {
+      autoSelectFamily: true,
+      attemptTimeoutMs: ADDRESS_ATTEMPT_TIMEOUT_MS,
+    });
+    assert.equal(ADDRESS_ATTEMPT_TIMEOUT_MS, 5_000);
+  });
+});

tests/router-fallback.test.js

@@ -320,6 +320,80 @@ describe("Claude Code canonical named routes", () => {
 });
 
 describe("same-provider OAuth account fallback", () => {
+  it("logs the individual socket causes hidden inside a Node AggregateError", async () => {
+    const store = createStore(tmpConfig());
+    store.seed({ providers: [chatgptAccount("prov_a", "token-a", 100)] });
+    const logger = captureLogger();
+    const router = createRouter({
+      store,
+      logger,
+      transportRetryDelayMs: 0,
+      transportRetryAttempts: 0,
+      fetchImpl: async () => {
+        const timeout = Object.assign(new Error("connect timed out 172.64.155.209:443"), {
+          code: "ETIMEDOUT",
+        });
+        const unreachable = Object.assign(new Error("connect unreachable 2606:4700::1:443"), {
+          code: "ENETUNREACH",
+        });
+        throw new TypeError("fetch failed", {
+          cause: new AggregateError([timeout, unreachable], "connection attempts failed"),
+        });
+      },
+    });
+
+    const result = await router.chatCompletions({
+      body: {
+        model: "chatgpt/gpt-5.4",
+        messages: [{ role: "user", content: "hello" }],
+        stream: false,
+      },
+    });
+
+    assert.equal(result.ok, false);
+    const failure = logger.entries.find((entry) => entry.meta?.event === "account_failure");
+    assert.match(failure.meta.transportCause, /ETIMEDOUT.*172\.64\.155\.209/);
+    assert.match(failure.meta.transportCause, /ENETUNREACH.*2606:4700/);
+    assert.deepEqual(store.load().providers[0].modelLocks, {});
+  });
+
+  it("retries an HTTP proxy connection reset without locking the account", async () => {
+    const store = createStore(tmpConfig());
+    store.seed({ providers: [chatgptAccount("prov_a", "token-a", 100)] });
+    const logger = captureLogger();
+    let calls = 0;
+    const router = createRouter({
+      store,
+      logger,
+      transportRetryDelayMs: 0,
+      fetchImpl: async () => {
+        calls += 1;
+        if (calls < 3) {
+          return new Response(
+            "upstream connect error or disconnect/reset before headers. reset reason: connection termination",
+            { status: 503 }
+          );
+        }
+        return responsesSuccessResponse("recovered");
+      },
+    });
+
+    const result = await router.chatCompletions({
+      body: {
+        model: "chatgpt/gpt-5.4",
+        messages: [{ role: "user", content: "hello" }],
+        stream: false,
+      },
+    });
+
+    assert.equal(result.ok, true, JSON.stringify(result.error));
+    assert.equal(calls, 3);
+    assert.deepEqual(store.load().providers[0].modelLocks, {});
+    const retries = logger.entries.filter((entry) => entry.meta?.event === "transport_retry_scheduled");
+    assert.equal(retries.length, 2);
+    assert.match(retries[0].meta.error, /disconnect\/reset before headers/);
+  });
+
   it("retries transport failures without locking the account", async () => {
     const store = createStore(tmpConfig());
     store.seed({ providers: [chatgptAccount("prov_a", "token-a", 100)] });