fix: query Nonce account

web3.js/src/connection.js

@@ -7,8 +7,9 @@ import jayson from 'jayson/lib/client/browser';
 import {struct} from 'superstruct';
 import {Client as RpcWebSocketClient} from 'rpc-websockets';
 
-import {DEFAULT_TICKS_PER_SLOT, NUM_TICKS_PER_SECOND} from './timing';
+import {NonceAccount} from './nonce-account';
 import {PublicKey} from './publickey';
+import {DEFAULT_TICKS_PER_SLOT, NUM_TICKS_PER_SECOND} from './timing';
 import {Transaction} from './transaction';
 import {sleep} from './util/sleep';
 import type {Blockhash} from './blockhash';
@@ -1149,6 +1150,55 @@ export class Connection {
     };
   }
 
+  /**
+   * Fetch the contents of a Nonce account from the cluster
+   */
+  async getNonceAndContext(
+    nonceAccount: PublicKey,
+    commitment: ?Commitment,
+  ): Promise<RpcResponseAndContext<NonceAccount>> {
+    const args = this._argsWithCommitment(
+      [nonceAccount.toBase58()],
+      commitment,
+    );
+    const unsafeRes = await this._rpcRequest('getAccountInfo', args);
+    const res = GetAccountInfoAndContextRpcResult(unsafeRes);
+    if (res.error) {
+      throw new Error(res.error.message);
+    }
+    assert(typeof res.result !== 'undefined');
+
+    const isV021 =
+      typeof res.result.context !== 'undefined' &&
+      typeof res.result.value !== 'undefined';
+
+    const slot = isV021 ? res.result.context.slot : NaN;
+    const resultValue = isV021 ? res.result.value : res.result;
+
+    if (!resultValue) {
+      throw new Error('Invalid request');
+    }
+
+    const value = NonceAccount.fromAccountData(Buffer.from(resultValue.data));
+
+    return {
+      context: {
+        slot,
+      },
+      value,
+    };
+  }
+  async getNonce(
+    nonceAccount: PublicKey,
+    commitment: ?Commitment,
+  ): Promise<NonceAccount> {
+    return await this.getNonceAndContext(nonceAccount, commitment)
+      .then(x => x.value)
+      .catch(e => {
+        throw e;
+      });
+  }
+
   /**
    * Request an allocation of lamports to the specified account
    */

web3.js/src/index.js

@@ -4,6 +4,7 @@ export {BpfLoader} from './bpf-loader';
 export {BudgetProgram} from './budget-program';
 export {Connection} from './connection';
 export {Loader} from './loader';
+export {NonceAccount} from './nonce-account';
 export {PublicKey} from './publickey';
 export {
   STAKE_CONFIG_ID,

web3.js/src/nonce-account.js

@@ -0,0 +1,40 @@
+// @flow
+import * as BufferLayout from 'buffer-layout';
+
+import type {Blockhash} from './blockhash';
+import * as Layout from './layout';
+import {PublicKey} from './publickey';
+
+/**
+ * See https://github.com/solana-labs/solana/blob/0ea2843ec9cdc517572b8e62c959f41b55cf4453/sdk/src/nonce_state.rs#L29-L32
+ *
+ * @private
+ */
+const NonceAccountLayout = BufferLayout.struct([
+  BufferLayout.u32('state'),
+  Layout.publicKey('authorizedPubkey'),
+  Layout.publicKey('hash'),
+]);
+
+/**
+ * NonceAccount class
+ */
+export class NonceAccount {
+  authorizedPubkey: PublicKey;
+  nonce: Blockhash;
+
+  /**
+   * Deserialize NonceAccount from the account data.
+   *
+   * @param buffer account data
+   * @return NonceAccount
+   */
+  static fromAccountData(buffer: Buffer): NonceAccount {
+    const nonceAccount = NonceAccountLayout.decode(buffer, 0);
+    nonceAccount.authorizedPubkey = new PublicKey(
+      nonceAccount.authorizedPubkey,
+    );
+    nonceAccount.nonce = new PublicKey(nonceAccount.nonce).toString();
+    return nonceAccount;
+  }
+}