Ready to use pipeline option

lib/datastore.js

@@ -12,20 +12,38 @@ var fs = require('fs')
 
 /**
  * Create a new collection
- * If a filename is provided, persist it to disk
+ * @param {String} options.filename Optional, datastore will be in-memory only if not provided
- * Otherwise keep it in memory (data will be lost when the application stops)
+ * @param {Boolean} options.inMemoryOnly Optional, default to false
+ * @param {Boolean} options.pipeline Optional, defaults to false, pipeline appends to the data file (enable to return before writes are persisted to disk for greater speed)
  */
-function Datastore (filename) {
+function Datastore (options) {
+  var filename;
+
+  // Retrocompatibility with v0.6 and before
+  if (typeof options === 'string') {
+    filename = options;
+    this.inMemoryOnly = false;   // Default
+    this.pipeline = false;       // Default
+  } else {
+    options = options || {};
+    filename = options.filename
+    this.inMemoryOnly = options.inMemoryOnly || false;
+    this.pipeline = options.pipeline || false;
+  }
+
   if (!filename || typeof filename !== 'string' || filename.length === 0) {
     this.filename = null;
+    this.inMemoryOnly = true;
   } else {
     this.filename = filename;
   }
 
   this.executor = new Executor();
+  if (this.pipeline) { this.persistenceExecutor = new Executor(); }
 
   // We keep internally the number of lines in the datafile
   // This will be used when/if I implement autocompacting when the datafile grows too big
+  // For now it is not urgent as autocompaction happens upon every restart
   this.datafileSize = 0;
 
   // Indexed by field name, dot notation can be used
@@ -202,17 +220,15 @@ Datastore.prototype._loadDatabase = function (cb) {
     , self = this
     ;
 
+  self.resetIndexes();
+  self.datafileSize = 0;
+
   // In-memory only datastore
-  if (!self.filename) { return callback(); }
+  if (self.inMemoryOnly) { return callback(); }
 
   customUtils.ensureDirectoryExists(path.dirname(self.filename), function (err) {
     fs.exists(self.filename, function (exists) {
-      if (!exists) {
+      if (!exists) { return fs.writeFile(self.filename, '', 'utf8', function (err) { callback(err); }); }
-        self.resetIndexes();
-        self.datafileSize = 0;
-        fs.writeFile(self.filename, '', 'utf8', function (err) { return callback(err); });
-        return;
-      }
 
       fs.readFile(self.filename, 'utf8', function (err, rawData) {
         if (err) { return callback(err); }
@@ -299,14 +315,14 @@ Datastore.prototype.persistCachedDatabase = function (cb) {
  * @param {Array} newDocs Can be empty if no doc was updated/removed
  * @param {Function} cb Optional, signature: err
  */
-Datastore.prototype.persistNewState = function (newDocs, cb) {
+Datastore.prototype._persistNewState = function (newDocs, cb) {
   var self = this
     , toPersist = ''
     , callback = cb || function () {}
     ;
 
   // In-memory only datastore
-  if (!self.filename) { return callback(); }
+  if (self.inMemoryOnly) { return callback(); }
 
   self.datafileSize += newDocs.length;
 
@@ -320,6 +336,9 @@ Datastore.prototype.persistNewState = function (newDocs, cb) {
     return callback(err);
   });
 };
+Datastore.prototype.persistNewState = function (newDocs, cb) {
+  this._persistNewState(newDocs, cb);
+};
 
 
 /**