try to GetTransaction working.

src/bitcoindjs.cc

@@ -877,6 +877,9 @@ async_get_block_after(uv_work_t *req) {
  * bitcoind.getTx(hash, callback)
  */
 
+static bool
+GetTransaction_(const uint256 &hash, CTransaction &txOut, uint256 &hashBlock, bool fAllowSlow);
+
 NAN_METHOD(GetTx) {
   NanScope();
 
@@ -916,7 +919,7 @@ NAN_METHOD(GetTx) {
   uint256 hashBlock(blockHash);
   CTransaction tx;
 
-  if (!GetTransaction(hash, tx, hashBlock, noBlockHash ? true : false)) {
+  if (!GetTransaction_(hash, tx, hashBlock, noBlockHash ? true : false)) {
     Local<Value> err = Exception::Error(String::New("Bad Transaction."));
     const unsigned argc = 1;
     Local<Value> argv[argc] = { err };
@@ -1031,6 +1034,65 @@ NAN_METHOD(GetTx) {
   }
 }
 
+static bool
+GetTransaction_(const uint256 &hash, CTransaction &txOut, uint256 &hashBlock, bool fAllowSlow) {
+  CBlockIndex *pindexSlow = NULL;
+  {
+    LOCK(cs_main);
+    {
+      if (mempool.lookup(hash, txOut)) {
+        return true;
+      }
+    }
+
+    if (0 && fTxIndex) {
+      CDiskTxPos postx;
+      if (pblocktree->ReadTxIndex(hash, postx)) {
+        CAutoFile file(OpenBlockFile(postx, true), SER_DISK, CLIENT_VERSION);
+        CBlockHeader header;
+        try {
+          file >> header;
+          fseek(file, postx.nTxOffset, SEEK_CUR);
+          file >> txOut;
+        } catch (std::exception &e) {
+          return error("%s : Deserialize or I/O error - %s", __PRETTY_FUNCTION__, e.what());
+        }
+        hashBlock = header.GetHash();
+        if (txOut.GetHash() != hash)
+          return error("%s : txid mismatch", __PRETTY_FUNCTION__);
+        return true;
+      }
+    }
+
+    if (fAllowSlow) { // use coin database to locate block that contains transaction, and scan it
+      int nHeight = -1;
+      {
+        CCoinsViewCache &view = *pcoinsTip;
+        CCoins coins;
+        if (view.GetCoins(hash, coins))
+          nHeight = coins.nHeight;
+      }
+      if (nHeight > 0)
+        pindexSlow = chainActive[nHeight];
+    }
+  }
+
+  if (pindexSlow) {
+    CBlock block;
+    if (ReadBlockFromDisk(block, pindexSlow)) {
+      BOOST_FOREACH(const CTransaction &tx, block.vtx) {
+        if (tx.GetHash() == hash) {
+          txOut = tx;
+          hashBlock = pindexSlow->GetBlockHash();
+          return true;
+        }
+      }
+    }
+  }
+
+  return false;
+}
+
 /**
  * Init
  */