Merge pull request #202 from pnagurny/feature/main-chain

Add isMainChain method

Author: Braydon Fuller

docs/services/bitcoind.md

@@ -8,6 +8,7 @@ The bitcoin service adds a native interface to Bitcoin Core for querying informa
 - `bitcoind.getBlock(blockHash|blockHeight, callback)` - Get any block asynchronously by block hash or height as a node buffer.
 - `bitcoind.isSpent(txid, outputIndex)` - Returns a boolean if a txid and outputIndex is already spent.
 - `bitcoind.getBlockIndex(blockHash)` - Will return the block chain work and previous hash.
+- `bitcoind.isMainChain(blockHash)` - Returns true if block is on the main chain. Returns false if it is an orphan.
 - `bitcoind.estimateFee(blocks)` - Estimates the fees required to have a transaction included in the number of blocks specified as the first argument.
 - `bitcoind.sendTransaction(transaction, allowAbsurdFees)` - Will attempt to add a transaction to the mempool and broadcast to peers.
 - `bitcoind.getTransaction(txid, queryMempool, callback)` - Get any tx asynchronously by reading it from disk, with an argument to optionally not include the mempool.

integration/regtest-node.js

@@ -137,6 +137,8 @@ describe('Node Functionality', function() {
     });
   });
 
+  var invalidatedBlockHash;
+
   it('will handle a reorganization', function(done) {
 
     var count;
@@ -157,12 +159,12 @@ describe('Node Functionality', function() {
           if (err) {
             return next(err);
           }
-          blockHash = response.result;
+          invalidatedBlockHash = response.result;
           next();
         });
       },
       function(next) {
-        client.invalidateBlock(blockHash, next);
+        client.invalidateBlock(invalidatedBlockHash, next);
       },
       function(next) {
         client.getBlockCount(function(err, response) {
@@ -212,4 +214,9 @@ describe('Node Functionality', function() {
     });
 
   });
+
+  it('isMainChain() will return false for stale/orphan block', function(done) {
+    node.services.bitcoind.isMainChain(invalidatedBlockHash).should.equal(false);
+    setImmediate(done);
+  });
 });

integration/regtest.js

@@ -251,6 +251,14 @@ describe('Daemon Binding Functionality', function() {
     });
   });
 
+  describe('isMainChain', function() {
+    [1,2,3,4,5,6,7,8,9].forEach(function(i) {
+      it('block ' + i + ' is on the main chain', function() {
+        bitcoind.isMainChain(blockHashes[i]).should.equal(true);
+      });
+    });
+  });
+
   describe('send transaction functionality', function() {
 
     it('will not error and return the transaction hash', function() {

lib/services/bitcoind.js

@@ -189,6 +189,10 @@ Bitcoin.prototype.getBlockIndex = function(blockHash) {
   return bindings.getBlockIndex(blockHash);
 };
 
+Bitcoin.prototype.isMainChain = function(blockHash) {
+  return bindings.isMainChain(blockHash);
+};
+
 Bitcoin.prototype.estimateFee = function(blocks) {
   return bindings.estimateFee(blocks);
 };

src/libbitcoind.cc

@@ -1350,6 +1350,36 @@ NAN_METHOD(GetBlockIndex) {
   NanReturnValue(obj);
 };
 
+
+/**
+ * IsMainChain()
+ * bitcoind.isMainChain()
+ *
+ * @param {string} - block hash
+ * @returns {boolean} - True if the block is in the main chain. False if it is an orphan.
+ */
+NAN_METHOD(IsMainChain) {
+  Isolate* isolate = Isolate::GetCurrent();
+  HandleScope scope(isolate);
+
+  CBlockIndex* blockIndex;
+
+  String::Utf8Value hash_(args[0]->ToString());
+  std::string hashStr = std::string(*hash_);
+  uint256 hash = uint256S(hashStr);
+  if (mapBlockIndex.count(hash) == 0) {
+    NanReturnValue(Undefined(isolate));
+  } else {
+    blockIndex = mapBlockIndex[hash];
+  }
+
+  if (chainActive.Contains(blockIndex)) {
+    NanReturnValue(NanNew<Boolean>(true));
+  } else {
+    NanReturnValue(NanNew<Boolean>(false));
+  }
+}
+
 /**
  * GetInfo()
  * bitcoindjs.getInfo()
@@ -1606,6 +1636,7 @@ init(Handle<Object> target) {
   NODE_SET_METHOD(target, "getInfo", GetInfo);
   NODE_SET_METHOD(target, "isSpent", IsSpent);
   NODE_SET_METHOD(target, "getBlockIndex", GetBlockIndex);
+  NODE_SET_METHOD(target, "isMainChain", IsMainChain);
   NODE_SET_METHOD(target, "getMempoolOutputs", GetMempoolOutputs);
   NODE_SET_METHOD(target, "addMempoolUncheckedTransaction", AddMempoolUncheckedTransaction);
   NODE_SET_METHOD(target, "sendTransaction", SendTransaction);

src/libbitcoind.h

@@ -22,6 +22,8 @@ NAN_METHOD(OnBlocksReady);
 NAN_METHOD(OnTipUpdate);
 NAN_METHOD(StopBitcoind);
 NAN_METHOD(GetBlock);
+NAN_METHOD(GetBlockIndex);
+NAN_METHOD(IsMainChain);
 NAN_METHOD(GetTransaction);
 NAN_METHOD(GetInfo);
 NAN_METHOD(IsSpent);

test/services/bitcoind.unit.js

@@ -371,6 +371,7 @@ describe('Bitcoin Service', function() {
       ['getBlock', 2],
       ['isSpent', 2],
       ['getBlockIndex', 1],
+      ['isMainChain', 1],
       ['estimateFee', 1],
       ['sendTransaction', 2],
       ['getTransaction', 3],