Wallet subaddress creation with retry recovery

tests/monero-observer.test.ts

@@ -1,7 +1,9 @@
 import test from 'node:test';
 import assert from 'node:assert/strict';
+import { keccak } from 'hash-wasm';
 import { ADDITIONAL_MARKET_FEE } from '../shared/market.ts';
-import { createMoneroWalletObserver, loadMoneroObserverConfig, type MoneroFixtureTransport } from '../server/market/monero-observer.ts';
+import { createMoneroDepositAddressRpc, createMoneroWalletObserver, loadMoneroObserverConfig,
+  type MoneroFixtureTransport } from '../server/market/monero-observer.ts';
 
 const config = { network: 'mainnet' as const, url: 'http://127.0.0.1:18083/json_rpc', username: 'fixture', password: 'not-a-live-secret' };
 function response(id: string, result: Record<string, unknown>, status = 200, type = 'application/json') {
@@ -21,6 +23,18 @@ function fakeTransport(incoming: Record<string, unknown>[] = []): { transport: M
   };
   return { transport, calls };
 }
+async function syntheticSubaddress(fill = 3) {
+  const prefix = Uint8Array.from([42, ...Array(64).fill(fill)]);
+  const data = Buffer.concat([prefix, Buffer.from((await keccak(prefix, 256)).slice(0, 8), 'hex')]);
+  const alphabet = '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz';
+  let encoded = '';
+  for (let i = 0; i < data.length; i += 8) {
+    const chunk = data.subarray(i, i + 8); let n = BigInt(`0x${chunk.toString('hex')}`), text = '';
+    while (n) { text = alphabet[Number(n % 58n)] + text; n /= 58n; }
+    encoded += text.padStart(chunk.length === 8 ? 11 : 7, '1');
+  }
+  return encoded;
+}
 
 test('read-only Monero observer preserves uint64 amount text and returns observations without crediting balances', async () => {
   const { transport, calls } = fakeTransport([{ txid: 'a'.repeat(64), address: ADDITIONAL_MARKET_FEE.address,
@@ -28,6 +42,7 @@ test('read-only Monero observer preserves uint64 amount text and returns observa
     timestamp: 1_800_000_000, unlock_time: 0, locked: false, double_spend_seen: false,
     subaddr_index: { major: 0, minor: 7 } }]);
   const observer = createMoneroWalletObserver(config, transport);
+  assert.equal('createSubaddress' in observer, false);
   const page = await observer.scanIncoming(90);
   assert.equal(page.network, 'mainnet'); assert.equal(page.walletHeight, 100);
   assert.equal(page.primaryAddress, ADDITIONAL_MARKET_FEE.address);
@@ -42,6 +57,38 @@ test('read-only Monero observer preserves uint64 amount text and returns observa
   assert.equal(Object.keys(observer).some(key => /transfer|sweep|send|credit/i.test(key)), false);
 });
 
+test('deposit-address RPC client is narrowly allow-listed and creates only one verified subaddress', async () => {
+  const subaddress = await syntheticSubaddress();
+  const calls: { method: string; params: unknown }[] = [];
+  const transport: MoneroFixtureTransport = async (_url, init) => {
+    const body = JSON.parse(init.body as string) as { id: string; method: string; params: unknown };
+    calls.push({ method: body.method, params: body.params });
+    if (body.method === 'get_address') return response(body.id, { address: ADDITIONAL_MARKET_FEE.address,
+      addresses: [{ address: subaddress, label: 'wikideck-deposit-v1:fixture', address_index: 7, used: false }], status: 'OK' });
+    if (body.method === 'create_address') return response(body.id, { address: subaddress, address_index: 7,
+      address_indices: [7], addresses: [subaddress], status: 'OK' });
+    return response(body.id, { height: 100, status: 'OK' });
+  };
+  const rpc = createMoneroDepositAddressRpc(config, transport);
+  assert.deepEqual(await rpc.getSubaddress(0, 7), { address: subaddress, label: 'wikideck-deposit-v1:fixture' });
+  assert.deepEqual(await rpc.createSubaddress(0, 'wikideck-deposit-v1:fixture'), { address: subaddress, addressIndex: 7 });
+  assert.deepEqual(calls, [
+    { method: 'get_address', params: { account_index: 0, address_index: [7] } },
+    { method: 'create_address', params: { account_index: 0, label: 'wikideck-deposit-v1:fixture', count: 1 } },
+  ]);
+  await assert.rejects(rpc.getSubaddress(0, 8), /different subaddress index/);
+  await assert.rejects(rpc.createSubaddress(0, 'bad\nlabel'), /parameters/);
+
+  let unexpectedCalls = 0;
+  const onlyAddressTransport: MoneroFixtureTransport = async (_url, init) => {
+    unexpectedCalls++;
+    const body = JSON.parse(init.body as string) as { id: string; method: string };
+    return response(body.id, { height: 100, status: 'OK' });
+  };
+  await assert.rejects(createMoneroDepositAddressRpc(config, onlyAddressTransport).getSubaddress(0, 0), /expected/);
+  assert.equal(unexpectedCalls, 1);
+});
+
 test('observer refuses non-loopback plaintext, URL credentials and malformed height ranges', async () => {
   assert.throws(() => createMoneroWalletObserver({ ...config, url: 'http://wallet.example/json_rpc' }), /HTTPS/);
   assert.throws(() => createMoneroWalletObserver({ ...config, url: 'http://localhost/json_rpc' }), /HTTPS/);