Umarchaller impl start

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

lib/bindings/http/unmarshaller_0_2.js

@@ -0,0 +1,40 @@
+
+const content_type_header = "content-type";
+const ce_structured_content_type = "application/cloudevents";
+
+/**
+ * Level 0 of validation: is that string? is that JSON?
+ */
+function validate_and_parse_as_json(payload) {
+  var json = payload;
+
+  if( (typeof payload) === "string"){
+    try {
+      json = JSON.parse(payload);
+
+    }catch(e) {
+      throw {message: "Invalid payload", errors: e};
+    }
+
+  } else if( (typeof payload) !== "object"){
+    // anything else
+    throw {message: "Invalid payload type, allowed are: string or object"};
+  }
+
+  return json;
+}
+
+var Unmarshaller = function() {
+
+}
+
+Unmarshaller.prototype.unmarshall = function(payload, headers) {
+
+  var valid0 = validate_and_parse_as_json(payload);
+
+  //TODO binary or structured ?
+  //"Content-Type"
+
+}
+
+module.exports = Unmarshaller;