Valid Transaction Data | Code

15Dkatz · Sep 29, 2022 · 5167c4d · 5167c4d
1 parent 4bda317
commit 5167c4d
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Showing 2 changed files with 54 additions and 15 deletions.
diff --git a/blockchain/index.js b/blockchain/index.js
@@ -1,5 +1,7 @@
 const Block = require('./block');
+const Transaction = require('../wallet/transaction');
 const { cryptoHash } = require('../util');
+const { REWARD_INPUT, MINING_REWARD } = require('../config');
 
 class Blockchain {
   constructor() {
@@ -18,22 +20,49 @@ class Blockchain {
   replaceChain(chain, onSuccess) {
     if (chain.length <= this.chain.length) {
       console.error('The incoming chain must be longer');
-
       return;
     }
 
     if (!Blockchain.isValidChain(chain)) {
       console.error('The incoming chain must be valid');
-
       return;
     }
 
     if (onSuccess) onSuccess();
-
     console.log('replacing chain with', chain);
     this.chain = chain;
   }
 
+  validTransactionData({ chain }) {
+    for (let i=1; i<chain.length; i++) {
+      const block = chain[i];
+      let rewardTransactionCount = 0;
+
+      for (let transaction of block.data) {
+        if (transaction.input.address === REWARD_INPUT.address) {
+          rewardTransactionCount += 1;
+
+          if (rewardTransactionCount > 1) {
+            console.error('Miner rewards exceeds limit');
+            return false;
+          }
+
+          if (Object.values(transaction.outputMap)[0] !== MINING_REWARD) {
+            console.error('Miner reward amount is invalid');
+            return false;
+          }
+        } else {
+          if (!Transaction.validTransaction(transaction)) {
+            console.error('Invalid transaction');
+            return false;
+          }
+        }
+      }
+    }
+
+    return true;
+  }
+
   static isValidChain(chain) {
     if(JSON.stringify(chain[0]) !== JSON.stringify(Block.genesis())) return false;
 

diff --git a/blockchain/index.test.js b/blockchain/index.test.js
@@ -5,13 +5,15 @@ const Wallet = require('../wallet');
 const Transaction = require('../wallet/transaction');
 
 describe('Blockchain', () => {
-  let blockchain, newChain, originalChain;
+  let blockchain, newChain, originalChain, errorMock;
 
   beforeEach(() => {
     blockchain = new Blockchain();
     newChain = new Blockchain();
+    errorMock = jest.fn();
 
     originalChain = blockchain.chain;
+    global.console.error = errorMock;
   });
 
   it('contains a `chain` Array instance', () => {
@@ -91,13 +93,11 @@ describe('Blockchain', () => {
   });
 
   describe('replaceChain()', () => {
-    let errorMock, logMock;
+    let logMock;
 
     beforeEach(() => {
-      errorMock = jest.fn();
       logMock = jest.fn();
 
-      global.console.error = errorMock;
       global.console.log = logMock;
     });
 
@@ -164,47 +164,57 @@ describe('Blockchain', () => {
     beforeEach(() => {
       wallet = new Wallet();
       transaction = wallet.createTransaction({ recipient: 'foo-address', amount: 65 });
-      rewardTransaction = Transaction.rewardTransaction({ address: wallet.publicKey });
+      rewardTransaction = Transaction.rewardTransaction({ minerWallet: wallet });
     });
 
     describe('and the transaction data is valid', () => {
       it('returns true', () => {
         newChain.addBlock({ data: [transaction, rewardTransaction] });
 
-        expect(blockchain.validTransactionData({ chain: newChain.chain }).toBe(true);
+        expect(blockchain.validTransactionData({ chain: newChain.chain })).toBe(true);
+        expect(errorMock).not.toHaveBeenCalled();
       });
     });
 
     describe('and the transaction data has multiple rewards', () => {
-      it('returns false', () => {
+      it('returns false and logs an error', () => {
         newChain.addBlock({ data: [transaction, rewardTransaction, rewardTransaction] });
 
         expect(blockchain.validTransactionData({ chain: newChain.chain })).toBe(false);
+        expect(errorMock).toHaveBeenCalled();
       });
     });
 
     describe('and the transaction data has at least one malformed outputMap', () => {
       describe('and the transaction is not a reward transaction', () => {
-        it('returns false', () => {
+        it('returns false and logs an error', () => {
           transaction.outputMap[wallet.publicKey] = 999999;
 
           newChain.addBlock({ data: [transaction, rewardTransaction ]});
 
           expect(blockchain.validTransactionData({ chain: newChain.chain })).toBe(false);
+          expect(errorMock).toHaveBeenCalled();
         });
       });
 
-      derscribe('and the transaction is a reward transaciton', () => {
-        it('returns false', () => {});
+      describe('and the transaction is a reward transaciton', () => {
+        it('returns false and logs an error', () => {
+          rewardTransaction.outputMap[wallet.publicKey] = 999999;
+
+          newChain.addBlock({ data: [transaction, rewardTransaction] });
+
+          expect(blockchain.validTransactionData({ chain: newChain.chain })).toBe(false);
+          expect(errorMock).toHaveBeenCalled();
+        });
       });
     });
 
     describe('and the transaction data has at least one malformed input', () => {
-      it('returns false', () => {});
+      it('returns false and logs an error', () => {});
     });
 
     describe('and a block contains multiple identical transactions', () => {
-      it('returns false', () => {});
+      it('returns false and logs an error', () => {});
     });
   });
 });