api and backwards compat work

lib/api_response.js

@@ -0,0 +1,44 @@
+'use strict';
+
+var ApiResponse = function(config) {
+  this.config = config;
+  this.reponse = config.response;
+  this.targetVersion = config.targetVersion;
+  this.version = config.version;
+};
+
+ApiResponse.factory = function factory(config) {
+  return new ApiResponse(config);
+};
+
+module.exports = ApiResponse;
+
+ApiResponse.prototype.respond = function respond(err, res, statusCodeOpt) {
+  var statusCode = statusCodeOpt || 200;
+  if (err) return this.response.json(statusCode, this._buildErr(err));
+  this.response.json(statusCode, this._buildResponse(res));
+};
+
+ApiResponse.prototype._buildErr = function _buildErr(err) {
+  // Handle err as either string or error type
+  var message = err.message || err; 
+  var name = err.name || null;
+
+  if (this.targetVersion < 1) return {err: message, errType: name};
+  return {err: {
+      name: name,
+      message: message,
+      version: this.version
+    }
+  };
+};
+
+ApiResponse.prototype._buildResponse = function _buildResponse(res) {
+  if (this.targetVersion < 1) {
+    var fullRes = res;
+    fullRes = fullRes || {};
+    fullRes.err = null;
+    return fullRes;
+  }
+  return {err: null, result: res || null, version: this.version};
+};