added human readable errors

lib/validation.js

@@ -49,11 +49,47 @@ module.exports = function (req, res, next) {
     
     // validate JSON
     validation = revalidator.validate(req.body, resource);
-    err = validation.valid ? err : validation;
+    err = validation.valid ? err : transform(validation);
+    
     next(err);
   } else {
     // continue
     next(err);
   }
 
-}
+}
+
+/**
+ * Transform revalidator errors into human redable errors.
+ */
+
+function transform(validation) {
+  var err = {}
+    , errors = validation.errors
+    , e
+    , prop
+  ;
+  
+  for(var i = 0, len = errors.length; i < len; i++) {
+    e = errors[i];
+    prop = e.property;
+    
+    switch(e.attribute) {
+      case 'type':
+        err[prop] = 'must be a ' + e.expected;
+      break;
+      case 'required':
+        err[prop] = 'is required';
+      break;
+      default:
+        err[prop] = 'is not valid'
+      break;
+    }
+  }
+  
+  // rename and add human readable errors
+  validation.validation = validation.errors;
+  validation.errors = err;
+  
+  return validation;
+}

test/validation.test.js

@@ -12,10 +12,11 @@ describe('Resource Actions', function(){
   
   describe('POST /todos', function(){
     it('should return an error when provided invalid data', function(done) {
-      todos.post({title: 123}, function (err, todo, req, res) {
+      todos.post({foo: 123, completed: 'flarg'}, function (err, todo, req, res) {
         expect(err).to.exist;
         expect(err.valid).to.equal(false);
-        expect(err.errors).to.have.length(1);
+        expect(err.validation).to.have.length(2);
+        expect(err.errors).to.be.a('object');
         expect(todo).to.not.exist;
         done();
       })