Catch up to solana 0.8 Transaction wire format changes

web3.js/src/connection.js

@@ -3,21 +3,11 @@
 import assert from 'assert';
 import fetch from 'node-fetch';
 import jayson from 'jayson/lib/client/browser';
-import nacl from 'tweetnacl';
 import {struct} from 'superstruct';
-import bs58 from 'bs58';
 
+import {bs58DecodePublicKey, Transaction} from './transaction';
 import type {Account, PublicKey} from './account';
-
-/**
- * @typedef {string} TransactionSignature
- */
-export type TransactionSignature = string;
-
-/**
- * @typedef {string} TransactionId
- */
-export type TransactionId = string;
+import type {TransactionSignature, TransactionId} from './transaction';
 
 type RpcRequest = (methodName: string, args: Array<any>) => any;
 
@@ -228,54 +218,31 @@ export class Connection {
     return res.result;
   }
 
+
   /**
    * Send tokens to another account
    */
   async sendTokens(from: Account, to: PublicKey, amount: number): Promise<TransactionSignature> {
-    const lastId = await this.getLastId();
-    const fee = 0;
+    const transaction = new Transaction();
+    transaction.fee = 0;
+    transaction.lastId = await this.getLastId();
+    transaction.keys[0] = from.publicKey;
+    transaction.keys[1] = to;
 
-    //
-    // TODO: Redo this...
-    //
+    // Forge a simple Budget Pay contract into `userdata`
+    // TODO: Clean this up
+    const userdata = Buffer.alloc(68); // 68 = serialized size of Budget enum
+    userdata.writeUInt32LE(60, 0);
+    userdata.writeUInt32LE(amount, 12);        // u64
+    userdata.writeUInt32LE(amount, 28);        // u64
+    const toData = bs58DecodePublicKey(to);
+    toData.copy(userdata, 36);
+    transaction.userdata = userdata;
 
-    // Build the transaction data to be signed.
-    const transactionData = Buffer.alloc(124);
-    transactionData.writeUInt32LE(amount, 4);        // u64
-    transactionData.writeUInt32LE(amount - fee, 20); // u64
-    transactionData.writeUInt32LE(32, 28);           // length of public key (u64)
-    {
-      const toBytes = Buffer.from(bs58.decode(to));
-      assert(toBytes.length === 32);
-      toBytes.copy(transactionData, 36);
-    }
-
-    transactionData.writeUInt32LE(32, 68);          // length of last id (u64)
-    {
-      const lastIdBytes = Buffer.from(bs58.decode(lastId));
-      assert(lastIdBytes.length === 32);
-      lastIdBytes.copy(transactionData, 76);
-    }
-
-    // Sign it
-    const signature = nacl.sign.detached(transactionData, from.secretKey);
-    assert(signature.length === 64);
-
-    // Build the over-the-wire transaction buffer
-    const wireTransaction = Buffer.alloc(236);
-    wireTransaction.writeUInt32LE(64, 0);  // signature length (u64)
-    Buffer.from(signature).copy(wireTransaction, 8);
-
-
-    wireTransaction.writeUInt32LE(32, 72);  // public key length (u64)
-    {
-      const fromBytes = Buffer.from(bs58.decode(from.publicKey));
-      assert(fromBytes.length === 32);
-      fromBytes.copy(wireTransaction, 80);
-    }
-    transactionData.copy(wireTransaction, 112);
+    transaction.sign(from);
 
     // Send it
+    const wireTransaction = transaction.serialize();
     const unsafeRes = await this._rpcRequest('sendTransaction', [[...wireTransaction]]);
     const res = SendTokensRpcResult(unsafeRes);
     if (res.error) {

web3.js/src/index.js

@@ -1,3 +1,4 @@
 // @flow
 export {Account} from './account';
 export {Connection} from './connection';
+export {Transaction} from './transaction';

web3.js/src/transaction.js

@@ -0,0 +1,134 @@
+// @flow
+
+import assert from 'assert';
+import nacl from 'tweetnacl';
+import bs58 from 'bs58';
+
+import type {Account, PublicKey} from './account';
+
+/**
+ * @private
+ */
+export function bs58DecodePublicKey(key: PublicKey): Buffer {
+  const keyBytes = Buffer.from(bs58.decode(key));
+  assert(keyBytes.length === 32);
+  return keyBytes;
+}
+
+/**
+ * @typedef {string} TransactionSignature
+ */
+export type TransactionSignature = string;
+
+/**
+ * @typedef {string} TransactionId
+ */
+export type TransactionId = string;
+
+/**
+ * Mirrors the Transaction struct in src/transaction.rs
+ */
+export class Transaction {
+
+  /**
+   * Current signature of the transaction.  Typically created by invoking the
+   * `sign()` method
+   */
+  signature: ?Buffer;
+
+  /**
+   * Public keys to include in this transaction
+   */
+  keys: Array<PublicKey> = [];
+
+  /**
+   * A recent transaction id.  Must be populated by the caller
+   */
+  lastId: ?TransactionId;
+
+  /**
+   * Fee for this transaction
+   */
+  fee: number = 0;
+
+  /**
+   * Contract input userdata to include
+   */
+  userdata: Buffer = Buffer.alloc(0);
+
+  /**
+   * @private
+   */
+  _getSignData(): Buffer {
+    const {lastId} = this;
+    if (!lastId) {
+      throw new Error('Transaction lastId required');
+    }
+
+    // Start with a Buffer that should be large enough to fit any Transaction
+    const transactionData = Buffer.alloc(2048);
+
+    let pos = 0;
+
+    // serialize `this.keys`
+    transactionData.writeUInt32LE(this.keys.length, pos);  // u64
+    pos += 8;
+    for (let key of this.keys) {
+      const keyBytes = bs58DecodePublicKey(key);
+      keyBytes.copy(transactionData, pos);
+      pos += 32;
+    }
+
+    // serialize `this.lastId`
+    {
+      const lastIdBytes = Buffer.from(bs58.decode(lastId));
+      assert(lastIdBytes.length === 32);
+      lastIdBytes.copy(transactionData, pos);
+      pos += 32;
+    }
+
+    // serialize `this.fee`
+    transactionData.writeUInt32LE(this.fee, pos);        // u64
+    pos += 8;
+
+    // serialize `this.userdata`
+    if (this.userdata.length > 0) {
+      this.userdata.copy(transactionData, pos);
+      pos += this.userdata.length;
+    }
+
+    return transactionData.slice(0, pos);
+  }
+
+  /**
+   * Sign the Transaction with the specified account
+   *
+   * The Transaction must be assigned a valid `lastId` before invoking this method
+   */
+  sign(from: Account) {
+    const transactionData = this._getSignData();
+    this.signature = nacl.sign.detached(transactionData, from.secretKey);
+    assert(this.signature.length === 64);
+  }
+
+  /**
+   * Serialize the Transaction in the wire format.
+   *
+   * The Transaction must have a valid `signature` before invoking this method
+   */
+  serialize(): Buffer {
+    const {signature} = this;
+    if (!signature) {
+      throw new Error('Transaction has not been signed');
+    }
+
+    const transactionData = this._getSignData();
+    const wireTransaction = Buffer.alloc(
+      signature.length + transactionData.length
+    );
+
+    Buffer.from(signature).copy(wireTransaction, 0);
+    transactionData.copy(wireTransaction, signature.length);
+    return wireTransaction;
+  }
+}