Make sure type of the foreign key match the primary key

See https://github.com/strongloop/loopback/issues/353

lib/datasource.js

@@ -1579,22 +1579,26 @@ DataSource.prototype.idProperty = function (modelName) {
  * @param {String} foreignClassName The foreign model name
  */
 DataSource.prototype.defineForeignKey = function defineForeignKey(className, key, foreignClassName) {
-  // quit if key already defined
+  var pkType = null;
-  if (this.getModelDefinition(className).rawProperties[key]) return;
-
-  var defaultType = Number;
-  if (foreignClassName) {
   var foreignModel = this.getModelDefinition(foreignClassName);
   var pkName = foreignModel && foreignModel.idName();
   if (pkName) {
-      defaultType = foreignModel.properties[pkName].type;
+    pkType = foreignModel.properties[pkName].type;
   }
+  var model = this.getModelDefinition(className);
+  if (model.properties[key]) {
+    if (pkType) {
+      // Reset the type of the foreign key
+      model.rawProperties[key].type = model.properties[key].type = pkType;
     }
+    return;
+  }
+
   if (this.connector.defineForeignKey) {
     var cb = function (err, keyType) {
       if (err) throw err;
       // Add the foreign key property to the data source _models
-      this.defineProperty(className, key, {type: keyType || defaultType});
+      this.defineProperty(className, key, {type: keyType || pkType});
     }.bind(this);
     switch (this.connector.defineForeignKey.length) {
       case 4:
@@ -1607,7 +1611,7 @@ DataSource.prototype.defineForeignKey = function defineForeignKey(className, key
     }
   } else {
     // Add the foreign key property to the data source _models
-    this.defineProperty(className, key, {type: defaultType});
+    this.defineProperty(className, key, {type: pkType});
   }
 
 };

lib/relation-definition.js

@@ -336,7 +336,7 @@ RelationDefinition.hasMany = function hasMany(modelFrom, modelTo, params) {
 
   if (!params.through) {
     // obviously, modelTo should have attribute called `fk`
-    modelTo.dataSource.defineForeignKey(modelTo.modelName, fk, this.modelName);
+    modelTo.dataSource.defineForeignKey(modelTo.modelName, fk, modelFrom.modelName);
   }
 
   var scopeMethods = {
@@ -348,6 +348,9 @@ RelationDefinition.hasMany = function hasMany(modelFrom, modelTo, params) {
     scopeMethods.create = scopeMethod(definition, 'create');
     scopeMethods.add = scopeMethod(definition, 'add');
     scopeMethods.remove = scopeMethod(definition, 'remove');
+  } else {
+    scopeMethods.create = scopeMethod(definition, 'create');
+    scopeMethods.build = scopeMethod(definition, 'build');
   }
 
   // Mix the property and scoped methods into the prototype class
@@ -623,6 +626,11 @@ BelongsTo.prototype.create = function(targetModelData, cb) {
   var pk = this.definition.keyFrom;
   var modelInstance = this.modelInstance;
 
+  if (typeof targetModelData === 'function' && !cb) {
+    cb = targetModelData;
+    targetModelData = {};
+  }
+
   modelTo.create(targetModelData, function(err, targetModel) {
     if(!err) {
       modelInstance[fk] = targetModel[pk];
@@ -695,7 +703,7 @@ BelongsTo.prototype.related = function (refresh, params) {
       return cachedValue;
     }
   } else if (params === undefined) { // acts as sync getter
-    return modelInstance[fk];
+    return cachedValue;
   } else { // setter
     modelInstance[fk] = params;
     self.resetCache();
@@ -813,18 +821,30 @@ RelationDefinition.hasOne = function (modelFrom, modelTo, params) {
  * @param {String|Object} err Error string or object
  * @param {Object} The newly created target model instance
  */
-HasOne.prototype.create = function(targetModelData, cb) {
+HasOne.prototype.create = function (targetModelData, cb) {
   var self = this;
   var modelTo = this.definition.modelTo;
   var fk = this.definition.keyTo;
   var pk = this.definition.keyFrom;
   var modelInstance = this.modelInstance;
-  var relationName = this.definition.name
 
+  if (typeof targetModelData === 'function' && !cb) {
+    cb = targetModelData;
+    targetModelData = {};
+  }
   targetModelData = targetModelData || {};
   targetModelData[fk] = modelInstance[pk];
-  modelTo.create(targetModelData, function(err, targetModel) {
+  var query = {where: {}};
-    if(!err) {
+  query.where[fk] = targetModelData[fk]
+  modelTo.findOne(query, function(err, result) {
+    if(err) {
+      cb(err);
+    } else if(result) {
+      cb(new Error('HasOne relation cannot create more than one instance of '
+        + modelTo.modelName));
+    } else {
+      modelTo.create(targetModelData, function (err, targetModel) {
+        if (!err) {
           // Refresh the cache
           self.resetCache(targetModel);
           cb && cb(err, targetModel);
@@ -832,14 +852,46 @@ HasOne.prototype.create = function(targetModelData, cb) {
           cb && cb(err);
         }
       });
+    }
+  });
 };
 
+/**
+ * Create a target model instance
+ * @param {Object} targetModelData The target model data
+ * @callback {Function} [cb] Callback function
+ * @param {String|Object} err Error string or object
+ * @param {Object} The newly created target model instance
+ */
+HasMany.prototype.create = function (targetModelData, cb) {
+  var self = this;
+  var modelTo = this.definition.modelTo;
+  var fk = this.definition.keyTo;
+  var pk = this.definition.keyFrom;
+  var modelInstance = this.modelInstance;
+
+  if (typeof targetModelData === 'function' && !cb) {
+    cb = targetModelData;
+    targetModelData = {};
+  }
+  targetModelData = targetModelData || {};
+  targetModelData[fk] = modelInstance[pk];
+  modelTo.create(targetModelData, function(err, targetModel) {
+    if(!err) {
+      // Refresh the cache
+      self.addToCache(targetModel);
+      cb && cb(err, targetModel);
+    } else {
+      cb && cb(err);
+    }
+  });
+};
 /**
  * Build a target model instance
  * @param {Object} targetModelData The target model data
  * @returns {Object} The newly built target model instance
  */
-HasOne.prototype.build = function(targetModelData) {
+HasMany.prototype.build = HasOne.prototype.build = function(targetModelData) {
   var modelTo = this.definition.modelTo;
   var pk = this.definition.keyFrom;
   var fk = this.definition.keyTo;
@@ -865,7 +917,6 @@ HasOne.prototype.related = function (refresh, params) {
   var fk = this.definition.keyTo;
   var pk = this.definition.keyFrom;
   var modelInstance = this.modelInstance;
-  var relationName = this.definition.name;
 
   if (arguments.length === 1) {
     params = refresh;
@@ -907,7 +958,7 @@ HasOne.prototype.related = function (refresh, params) {
       return cachedValue;
     }
   } else if (params === undefined) { // acts as sync getter
-    return modelInstance[pk];
+    return cachedValue;
   } else { // setter
     params[fk] = modelInstance[pk];
     self.resetCache();

lib/scope.js

@@ -202,7 +202,9 @@ function defineScope(cls, targetClass, name, params, methods) {
       var prop = targetClass.definition.properties[i];
       if (prop) {
         var val = where[i];
-        if (typeof val !== 'object' || val instanceof prop.type) {
+        if (typeof val !== 'object' || val instanceof prop.type
+          || prop.type.name === 'ObjectID') // MongoDB key
+        {
           // Only pick the {propertyName: propertyValue}
           data[i] = where[i];
         }

test/relations.test.js

@@ -155,7 +155,7 @@ describe('relations', function () {
               should.not.exist(e);
               should.exist(l);
               l.should.be.an.instanceOf(List);
-              todo.list().should.equal(l.id);
+              todo.list().id.should.equal(l.id);
               done();
             });
           });
@@ -206,7 +206,7 @@ describe('relations', function () {
               should.not.exist(e);
               should.exist(act);
               act.should.be.an.instanceOf(Account);
-              supplier.account().should.equal(act.id);
+              supplier.account().id.should.equal(act.id);
               done();
             });
           });