fix(widgets): use HTTP polling for Solana tx confirmation (#8592)

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: Xaroz

.changeset/fix-solana-confirm-polling.md

@@ -0,0 +1,5 @@
+---
+'@hyperlane-xyz/widgets': patch
+---
+
+Replaced WebSocket-based `confirmTransaction` with HTTP polling (`getSignatureStatuses`) for Solana transaction confirmation. Fixed hangs with RPC providers that don't support `signatureSubscribe`.

typescript/widgets/src/walletIntegrations/solana.ts

@@ -11,6 +11,8 @@ import type { ITokenMetadata } from '@hyperlane-xyz/sdk/token/ITokenMetadata';
 import type { ChainName } from '@hyperlane-xyz/sdk/types';
 import type { WarpTypedTransaction } from '@hyperlane-xyz/sdk/warp/types';
 
+import { sleep } from '@hyperlane-xyz/utils';
+
 import { widgetLogger } from '../logger.js';
 
 import {
@@ -73,22 +75,63 @@ export function useSolanaTransactionFns(
       const connection = new Connection(rpcUrl, 'confirmed');
       const {
         context: { slot: minContextSlot },
-        value: { blockhash, lastValidBlockHeight },
+        value: { lastValidBlockHeight },
       } = await connection.getLatestBlockhashAndContext();
 
       logger.debug(`Sending tx on chain ${chainName}`);
       const signature = await sendSolTransaction(tx.transaction, connection, {
         minContextSlot,
       });
 
-      const confirm = (): Promise<TypedTransactionReceipt> =>
-        connection
-          .confirmTransaction({ blockhash, lastValidBlockHeight, signature })
-          .then(() => connection.getTransaction(signature))
-          .then((r) => ({
-            type: ProviderType.SolanaWeb3,
-            receipt: r!,
-          }));
+      const confirm = async (): Promise<TypedTransactionReceipt> => {
+        // Poll via HTTP instead of connection.confirmTransaction which
+        // relies on signatureSubscribe (WebSocket) — many RPC providers
+        // (e.g. Alchemy) don't support that method.
+        const POLL_INTERVAL_MS = 2000;
+        while (true) {
+          try {
+            const { value } = await connection.getSignatureStatuses([
+              signature,
+            ]);
+            const status = value?.[0];
+            if (status?.err) {
+              throw new Error(
+                `Transaction failed: ${JSON.stringify(status.err)}`,
+              );
+            }
+            if (
+              status?.confirmationStatus === 'confirmed' ||
+              status?.confirmationStatus === 'finalized'
+            ) {
+              break;
+            }
+            const blockHeight = await connection.getBlockHeight();
+            if (blockHeight > lastValidBlockHeight) {
+              throw new Error('Transaction expired: block height exceeded');
+            }
+          } catch (error) {
+            // Re-throw definitive failures (tx error, expiry)
+            if (
+              error instanceof Error &&
+              (error.message.startsWith('Transaction failed') ||
+                error.message.startsWith('Transaction expired'))
+            ) {
+              throw error;
+            }
+            // Tolerate transient RPC errors (timeouts, rate limits)
+            logger.warn('Transient error polling tx confirmation', error);
+          }
+          await sleep(POLL_INTERVAL_MS);
+        }
+        const tx = await connection.getTransaction(signature, {
+          commitment: 'confirmed',
+          maxSupportedTransactionVersion: 0,
+        });
+        if (!tx) {
+          throw new Error(`Transaction ${signature} confirmed but not found`);
+        }
+        return { type: ProviderType.SolanaWeb3, receipt: tx };
+      };
 
       return { hash: signature, confirm };
     },