Refactor toHttpError code into BoxError

src/boxerror.js

@@ -3,6 +3,7 @@
 'use strict';
 
 const assert = require('assert'),
+    HttpError = require('connect-lastmile').HttpError,
     util = require('util'),
     _ = require('underscore');
 
@@ -67,4 +68,30 @@ BoxError.prototype.setMessage = function (message) {
     assert.strictEqual(typeof message, 'string');
 
     this.message = message;
-};
+};
+
+// this is a class method for now in case error is not a BoxError
+BoxError.toHttpError = function (error) {
+    switch (error.reason) {
+    case BoxError.BAD_FIELD:
+        return new HttpError(400, error);
+    case BoxError.LICENSE_ERROR:
+        return new HttpError(402, error);
+    case BoxError.NOT_FOUND:
+        return new HttpError(404, error);
+    case BoxError.ALREADY_EXISTS:
+    case BoxError.BAD_STATE:
+    case BoxError.CONFLICT:
+        return new HttpError(409, error);
+    case BoxError.INVALID_CREDENTIALS:
+        return new HttpError(412, error);
+    case BoxError.EXTERNAL_ERROR:
+    case BoxError.NETWORK_ERROR:
+    case BoxError.FS_ERROR:
+        return new HttpError(424, error);
+    case BoxError.DATABASE_ERROR:
+    case BoxError.INTERNAL_ERROR:
+    default:
+        return new HttpError(500, error);
+    }
+};