[api test] Added `.sources` option for `nconf.Provider` for readonly configuration data

lib/nconf/provider.js

@@ -30,6 +30,7 @@ var Provider = exports.Provider = function (options) {
   this._env       = options.env       || false;
   this._reserved  = Object.keys(Provider.prototype);
   this._stores    = [];
+  this.sources    = [];
   
   //
   // Add the default `system` store for working with
@@ -38,6 +39,10 @@ var Provider = exports.Provider = function (options) {
   //
   this.add('system', options);
   
+  //
+  // Add any stores passed in through the options
+  // to this instance.
+  //
   if (options.type) {
     this.add(options.type, options);
   }
@@ -47,7 +52,20 @@ var Provider = exports.Provider = function (options) {
   else if (options.stores) {
     Object.keys(options.stores).forEach(function (name) {
       var store = options.stores[name];
-      self.add(store.name || store.type, store);
+      self.add(store.name || name || store.type, store);
+    });
+  }
+  
+  //
+  // Add any read-only sources to this instance
+  //
+  if (options.source) {
+    this.sources.push(this.create(options.source.type || options.source.name, options.source));
+  }
+  else if (options.sources) {
+    Object.keys(options.sources).forEach(function (name) {
+      var source = options.sources[name];
+      self.sources.push(self.create(source.type || source.name || name, source));
     });
   }
 };
@@ -122,6 +140,8 @@ Provider.prototype.add = function (name, options) {
   if (this[name].loadSync) {
     this[name].loadSync();
   }
+  
+  return this;
 };
 
 //
@@ -141,6 +161,7 @@ Provider.prototype.remove = function (name) {
   
   delete this[name];
   this._stores.splice(this._stores.indexOf(name), 1);
+  return this;
 };
 
 //
@@ -270,11 +291,11 @@ Provider.prototype.merge = function () {
 // Responds with an Object representing all keys associated in this instance.
 //
 Provider.prototype.load = function (callback) {
-  var self = this;
+  var self = this,
+      stores = this._stores.map(function (name) { return self[name] })
+                           .concat(this.sources);
   
-  function loadStoreSync(name) {
-    var store = self[name];
-    
+  function loadStoreSync(store) {
     if (!store.loadSync) {
       throw new Error('nconf store ' + store.type + ' has no loadSync() method');
     }
@@ -282,9 +303,7 @@ Provider.prototype.load = function (callback) {
     return store.loadSync();
   }
   
-  function loadStore(name, next) {
-    var store = self[name];
-    
+  function loadStore(store, next) {
     if (!store.load && !store.loadSync) {
       return next(new Error('nconf store ' + store.type + ' has no load() method'));
     }
@@ -300,10 +319,10 @@ Provider.prototype.load = function (callback) {
   // then do so.
   //
   if (!callback) {
-    return common.merge(this._stores.map(loadStoreSync));
+    return common.merge(stores.map(loadStoreSync));
   }
   
-  async.map(this._stores, loadStore, function (err, objs) {
+  async.map(stores, loadStore, function (err, objs) {
     return err ? callback(err) : callback(null, common.merge(objs));
   });
 };

test/provider-test.js

@@ -64,6 +64,23 @@ vows.describe('nconf/provider').addBatch({
           provider.merge(override);
           helpers.assertMerged(null, provider.file.store);
         }
+      },
+      "when sources are passed in": {
+        topic: new nconf.Provider({
+          sources: {
+            user: {
+              type: 'file',
+              file: files[0]
+            },
+            global: {
+              type: 'file',
+              file: files[1]
+            }
+          }
+        }),
+        "should have the result merged in": function (provider) {
+          helpers.assertMerged(null, provider.load());
+        }
       }
     }
   }