call for check

Signed-off-by: Fabio José <fabiojose@gmail.com>

lib/cloudevent.js

@@ -16,6 +16,10 @@ function Cloudevent(_spec, _formatter){
  * To format the payload using the formatter
  */
 Cloudevent.prototype.format = function(){
+  // Check the constraints
+  this.spec.check();
+
+  // Then, format
   return this.formatter.format(this.spec.payload);
 }
 

lib/specs/spec_0_2.js

@@ -7,6 +7,13 @@ function Spec_0_2(){
   };
 }
 
+/*
+ * Check the spec constraints.
+ */
+Spec_0_2.prototype.check = function(){
+
+}
+
 Spec_0_2.prototype.type = function(_type){
   this.payload['type'] = _type;
   return this;