From 09147f137866aa1e689bf8a6cfb63e65dd93017c Mon Sep 17 00:00:00 2001
From: Gandalf <gandalf@storm.pl>
Date: Fri, 12 Dec 2025 10:15:49 +0100
Subject: [PATCH] Add regex fallback for WASM isValidAccountName failures

TEMPORARY WORKAROUND for wax WASM thread-safety issue.

The wax WASM module isn't thread-safe - concurrent Server Component
requests calling chain.isValidAccountName() cause memory corruption:
"RuntimeError: memory access out of bounds"

This fix:
- Keeps wax as primary validation method
- Catches WASM errors and falls back to regex validation
- Logs warnings when fallback is used (helps track issue frequency)
- Documents as temporary with TODO and issue references

Once wax#140 is resolved, remove the try/catch and regex fallback.

Related: #758
See also: https://gitlab.syncad.com/hive/wax/-/issues/140
---
 apps/blog/utils/validate-links.ts | 66 ++++++++++++++++++++++++++++++-
 1 file changed, 64 insertions(+), 2 deletions(-)

diff --git a/apps/blog/utils/validate-links.ts b/apps/blog/utils/validate-links.ts
index fec5dfefc..68b701654 100644
--- a/apps/blog/utils/validate-links.ts
+++ b/apps/blog/utils/validate-links.ts
@@ -1,12 +1,74 @@
 import { getChain } from '@hive/transaction/lib/chain';
+import { getLogger } from '@ui/lib/logging';
+
+const logger = getLogger('app');
 
 export function isPermlinkValid(permlink: string): boolean {
   if (typeof permlink !== 'string') return false;
   return /^[a-z0-9-]{1,255}$/.test(permlink);
 }
 
+/**
+ * Validates Hive account names using wax library with regex fallback.
+ *
+ * TEMPORARY WORKAROUND: The wax WASM module isn't thread-safe - concurrent
+ * Server Component requests cause "memory access out of bounds" errors.
+ * We catch WASM errors and fall back to regex validation until wax is fixed.
+ *
+ * @see https://gitlab.syncad.com/hive/denser/-/issues/758
+ * @see https://gitlab.syncad.com/hive/wax/-/issues/140
+ *
+ * TODO: Remove regex fallback once wax thread-safety is resolved
+ */
 export async function isUsernameValid(accountName: string): Promise<boolean> {
   if (typeof accountName !== 'string') return false;
-  const chain = await getChain();
-  return chain.isValidAccountName(accountName);
+
+  try {
+    const chain = await getChain();
+    return chain.isValidAccountName(accountName);
+  } catch (error) {
+    // TEMPORARY: Log WASM failure and fall back to regex validation
+    // See: https://gitlab.syncad.com/hive/wax/-/issues/140
+    logger.warn({ err: error, accountName }, 'WASM isValidAccountName failed, using regex fallback');
+    return isUsernameValidRegex(accountName);
+  }
+}
+
+/**
+ * Regex fallback for Hive account name validation.
+ * Used when wax WASM fails due to concurrent access.
+ *
+ * Rules based on Hive blockchain consensus:
+ * - 3-16 characters
+ * - Lowercase letters, numbers, dots, hyphens only
+ * - Must start with a letter
+ * - Cannot end with hyphen or dot
+ * - Each segment (separated by dots) must start with a letter
+ * - No consecutive dots or hyphens
+ *
+ * TODO: Remove once wax thread-safety is resolved (see wax#140)
+ */
+function isUsernameValidRegex(accountName: string): boolean {
+  if (accountName.length < 3 || accountName.length > 16) return false;
+
+  // Must contain only lowercase letters, numbers, dots, and hyphens
+  if (!/^[a-z0-9.-]+$/.test(accountName)) return false;
+
+  // Must start with a letter
+  if (!/^[a-z]/.test(accountName)) return false;
+
+  // Cannot end with hyphen or dot
+  if (/[.-]$/.test(accountName)) return false;
+
+  // No consecutive dots or hyphens
+  if (/[.-]{2}/.test(accountName)) return false;
+
+  // Each segment must start with a letter
+  const segments = accountName.split('.');
+  for (const segment of segments) {
+    if (segment.length === 0) return false;
+    if (!/^[a-z]/.test(segment)) return false;
+  }
+
+  return true;
 }
-- 
GitLab