chain/mempool/node: expose getSpentView.

lib/blockchain/chain.js

@@ -1704,16 +1704,16 @@ Chain.prototype.hasPending = function hasPending(hash) {
 };
 
 /**
- * Get coin viewpoint.
+ * Get coin viewpoint (spent).
  * @method
  * @param {TX} tx
  * @returns {Promise} - Returns {@link CoinView}.
  */
 
-Chain.prototype.getCoinView = co(function* getCoinView(tx) {
+Chain.prototype.getSpentView = co(function* getSpentView(tx) {
   var unlock = yield this.locker.lock();
   try {
-    return yield this.db.getCoinView(tx);
+    return yield this.db.getSpentView(tx);
   } finally {
     unlock();
   }

lib/mempool/mempool.js

@@ -29,6 +29,8 @@ var layout = require('./layout');
 var LDB = require('../db/ldb');
 var Fees = require('./fees');
 var Map = require('../utils/map');
+var CoinView = require('../coins/coinview');
+var Coins = require('../coins/coins');
 var VerifyError = errors.VerifyError;
 var VerifyResult = errors.VerifyResult;
 
@@ -1603,7 +1605,22 @@ Mempool.prototype.isDoubleSpend = function isDoubleSpend(tx) {
  * Get coin viewpoint (lock).
  * @method
  * @param {TX} tx
- * @param {CoinView} view
+ * @returns {Promise} - Returns {@link CoinView}.
+ */
+
+Mempool.prototype.getSpentView = co(function* getSpentView(tx) {
+  var unlock = yield this.locker.lock();
+  try {
+    return yield this.getCoinView(tx);
+  } finally {
+    unlock();
+  }
+});
+
+/**
+ * Get coin viewpoint (no lock).
+ * @method
+ * @param {TX} tx
  * @returns {Promise} - Returns {@link CoinView}.
  */
 
@@ -1629,6 +1646,42 @@ Mempool.prototype.getCoinView = co(function* getCoinView(tx) {
   return view;
 });
 
+/**
+ * Get coin viewpoint (no lock).
+ * @method
+ * @param {TX} tx
+ * @returns {Promise} - Returns {@link CoinView}.
+ */
+
+Mempool.prototype.getCoinView = co(function* getCoinView(tx) {
+  var view = new CoinView();
+  var prevout = tx.getPrevout();
+  var i, hash, entry, coins;
+
+  for (i = 0; i < prevout.length; i++) {
+    hash = prevout[i];
+    entry = this.getEntry(hash);
+
+    if (entry) {
+      view.addTX(entry.tx, -1);
+      continue;
+    }
+
+    coins = yield this.chain.db.getCoins(hash);
+
+    if (!coins) {
+      coins = new Coins();
+      coins.hash = hash;
+      view.add(coins);
+      continue;
+    }
+
+    view.add(coins);
+  }
+
+  return view;
+});
+
 /**
  * Find missing outpoints.
  * @param {TX} tx

lib/node/fullnode.js

@@ -465,6 +465,18 @@ FullNode.prototype.getMeta = co(function* getMeta(hash) {
   return yield this.chain.db.getMeta(hash);
 });
 
+/**
+ * Retrieve a spent coin viewpoint from mempool or chain database.
+ * @param {TXMeta} meta
+ * @returns {Promise} - Returns {@link CoinView}.
+ */
+
+FullNode.prototype.getMetaView = co(function* getMetaView(meta) {
+  if (meta.height === -1)
+    return this.mempool.getSpentView(meta.tx);
+  return this.chain.getSpentView(meta.tx);
+});
+
 /**
  * Retrieve transactions pertaining to an
  * address from the mempool or chain database.