From 7316048afc1164ed91a004a8f4f58f3603df456f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Miroslav=20Bajto=C5=A1?= <miroslav@strongloop.com>
Date: Mon, 16 Jun 2014 16:13:24 +0200
Subject: [PATCH] lib/registry: `getModel` throws, add `findModel`

Rename `loopback.getModel` to `loopback.findModel`.

Implement `loopback.getModel` as a wrapper around `findModel` that
throws an error when the model as not found.
---
 lib/models/acl.js     |  4 ++--
 lib/models/change.js  |  2 +-
 lib/registry.js       | 18 +++++++++++++++++-
 test/loopback.test.js |  7 ++++++-
 4 files changed, 26 insertions(+), 5 deletions(-)

diff --git a/lib/models/acl.js b/lib/models/acl.js
index a3126b87..2c0abe57 100644
--- a/lib/models/acl.js
+++ b/lib/models/acl.js
@@ -261,7 +261,7 @@ ACL.resolvePermission = function resolvePermission(acls, req) {
  * @return {Object[]} An array of ACLs
  */
 ACL.getStaticACLs = function getStaticACLs(model, property) {
-  var modelClass = loopback.getModel(model);
+  var modelClass = loopback.findModel(model);
   var staticACLs = [];
   if (modelClass && modelClass.settings.acls) {
     modelClass.settings.acls.forEach(function (acl) {
@@ -343,7 +343,7 @@ ACL.checkPermission = function checkPermission(principalType, principalId,
       acls = acls.concat(dynACLs);
       resolved = self.resolvePermission(acls, req);
       if(resolved && resolved.permission === ACL.DEFAULT) {
-        var modelClass = loopback.getModel(model);
+        var modelClass = loopback.findModel(model);
         resolved.permission = (modelClass && modelClass.settings.defaultPermission) || ACL.ALLOW;
       }
       callback && callback(null, resolved);
diff --git a/lib/models/change.js b/lib/models/change.js
index 65420725..e66a8453 100644
--- a/lib/models/change.js
+++ b/lib/models/change.js
@@ -128,7 +128,7 @@ Change.idForModel = function(modelName, modelId) {
  */
 
 Change.findOrCreateChange = function(modelName, modelId, callback) {
-  assert(loopback.getModel(modelName), modelName + ' does not exist');
+  assert(loopback.findModel(modelName), modelName + ' does not exist');
   var id = this.idForModel(modelName, modelId);
   var Change = this;
 
diff --git a/lib/registry.js b/lib/registry.js
index b3666c0b..59c3d94d 100644
--- a/lib/registry.js
+++ b/lib/registry.js
@@ -176,10 +176,26 @@ registry.configureModel = function(ModelCtor, config) {
  * @param {String} modelName The model name
  * @returns {Model} The model class
  *
+ * @header loopback.findModel(modelName)
+ */
+registry.findModel = function(modelName) {
+  return this.Model.modelBuilder.models[modelName];
+};
+
+/**
+ * Look up a model class by name from all models created by
+ * `loopback.createModel()`. Throw an error when no such model exists.
+ *
+ * @param {String} modelName The model name
+ * @returns {Model} The model class
+ *
  * @header loopback.getModel(modelName)
  */
 registry.getModel = function(modelName) {
-  return this.Model.modelBuilder.models[modelName];
+  var model = this.findModel(modelName);
+  if (model) return model;
+
+  throw new Error('Model not found: ' + modelName);
 };
 
 /**
diff --git a/test/loopback.test.js b/test/loopback.test.js
index bb0ef95a..c4dcf313 100644
--- a/test/loopback.test.js
+++ b/test/loopback.test.js
@@ -107,7 +107,7 @@ describe('loopback', function() {
         });
         assert(loopback.getModel('MyModel') === MyModel);
         assert(loopback.getModel('MyCustomModel') === MyCustomModel);
-        assert(loopback.getModel('Invalid') === undefined);
+        assert(loopback.findModel('Invalid') === undefined);
       });
       it('should be able to get model by type', function () {
         var MyModel = loopback.createModel('MyModel', {}, {
@@ -124,6 +124,11 @@ describe('loopback', function() {
         assert(loopback.getModelByType(MyModel) === MyCustomModel);
         assert(loopback.getModelByType(MyCustomModel) === MyCustomModel);
       });
+
+      it('should throw when the model does not exist', function() {
+        expect(function() { loopback.getModel(uniqueModelName); })
+          .to.throw(Error, new RegExp('Model not found: ' + uniqueModelName));
+      });
     });
   });