db: change iterator api to be more loop-friendly.

YusukeShimizu · Oct 18, 2017 · 4d8ca8c · 4d8ca8c
1 parent 1c1e429
commit 4d8ca8c
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Showing 8 changed files with 183 additions and 228 deletions.
diff --git a/lib/blockchain/chaindb.js b/lib/blockchain/chaindb.js
@@ -1881,7 +1881,9 @@ ChainDB.prototype.pruneBlock = async function pruneBlock(entry) {
 
 ChainDB.prototype.saveFlags = function saveFlags() {
   const flags = ChainFlags.fromOptions(this.options);
-  return this.db.put(layout.O, flags.toRaw());
+  const batch = this.db.batch();
+  batch.put(layout.O, flags.toRaw());
+  return batch.write();
 };
 
 /**

diff --git a/lib/db/level.js b/lib/db/level.js
@@ -17,37 +17,19 @@ DB.prototype.close = function close(callback) {
 };
 
 DB.prototype.get = function get(key, options, callback) {
-  if (this.bufferKeys && Buffer.isBuffer(key))
-    key = key.toString('hex');
-  this.level.get(key, options, callback);
+  this.level.get(toHex(key), options, callback);
 };
 
 DB.prototype.put = function put(key, value, options, callback) {
-  if (this.bufferKeys && Buffer.isBuffer(key))
-    key = key.toString('hex');
-  this.level.put(key, value, options, callback);
+  this.level.put(toHex(key), value, options, callback);
 };
 
 DB.prototype.del = function del(key, options, callback) {
-  if (this.bufferKeys && Buffer.isBuffer(key))
-    key = key.toString('hex');
-  this.level.del(key, options, callback);
+  this.level.del(toHex(key), options, callback);
 };
 
-DB.prototype.batch = function batch(ops, options, callback) {
-  if (!ops)
-    return new Batch(this);
-
-  if (this.bufferKeys) {
-    for (const op of ops) {
-      if (Buffer.isBuffer(op.key))
-        op.key = op.key.toString('hex');
-    }
-  }
-
-  this.level.batch(ops, options, callback);
-
-  return undefined;
+DB.prototype.batch = function batch() {
+  return new Batch(this);
 };
 
 DB.prototype.iterator = function iterator(options) {
@@ -65,17 +47,13 @@ function Batch(db) {
 }
 
 Batch.prototype.put = function put(key, value) {
-  if (this.db.bufferKeys && Buffer.isBuffer(key))
-    key = key.toString('hex');
-  this.batch.put(key, value);
+  this.batch.put(toHex(key), value);
   this.hasOps = true;
   return this;
 };
 
 Batch.prototype.del = function del(key) {
-  if (this.db.bufferKeys && Buffer.isBuffer(key))
-    key = key.toString('hex');
-  this.batch.del(key);
+  this.batch.del(toHex(key));
   this.hasOps = true;
   return this;
 };
@@ -93,28 +71,30 @@ Batch.prototype.clear = function clear() {
 };
 
 function Iterator(db, options) {
-  if (db.bufferKeys) {
-    if (Buffer.isBuffer(options.gt))
-      options.gt = options.gt.toString('hex');
-    if (Buffer.isBuffer(options.gte))
-      options.gte = options.gte.toString('hex');
-    if (Buffer.isBuffer(options.lt))
-      options.lt = options.lt.toString('hex');
-    if (Buffer.isBuffer(options.lte))
-      options.lte = options.lte.toString('hex');
-  }
-  options.keyAsBuffer = false;
+  const opt = {
+    gt: toHex(options.gt),
+    gte: toHex(options.gte),
+    lt: toHex(options.lt),
+    lte: toHex(options.lte),
+    limit: options.limit,
+    reverse: options.reverse,
+    keys: options.keys,
+    values: options.values,
+    keyAsBuffer: false,
+    valueAsBuffer: true
+  };
+
   this.db = db;
-  this.iter = db.level.iterator(options);
-  this._end = false;
+  this.iter = db.level.iterator(opt);
+  this.ended = false;
 }
 
 Iterator.prototype.next = function next(callback) {
   this.iter.next((err, key, value) => {
     // Hack for level-js: it doesn't actually
     // end iterators -- it keeps streaming keys
     // and values.
-    if (this._end)
+    if (this.ended)
       return;
 
     if (err) {
@@ -138,18 +118,22 @@ Iterator.prototype.next = function next(callback) {
 };
 
 Iterator.prototype.seek = function seek(key) {
-  if (this.db.bufferKeys && Buffer.isBuffer(key))
-    key = key.toString('hex');
-  this.iter.seek(key);
+  this.iter.seek(toHex(key));
 };
 
 Iterator.prototype.end = function end(callback) {
-  if (this._end) {
+  if (this.ended) {
     callback(new Error('end() already called on iterator.'));
     return;
   }
-  this._end = true;
+  this.ended = true;
   this.iter.end(callback);
 };
 
+function toHex(key) {
+  if (Buffer.isBuffer(key))
+    return key.toString('hex');
+  return key;
+}
+
 module.exports = DB;