Error Service
=============

.. list-table::
   :header-rows: 1

   * - Technical name
     - Dependencies
   * - ``crash_manager``
     - `\ ``dialog_manager`` <dialog_manager.md>`_


Overview
--------

The ``crash manager service`` responsibility is to display a dialog
when an rpc error or a client error occurs. No interaction with the
crash manager is possible. If deployed, the crash manager simply listens
to some event and opens the appropriate dialogs when needed.

API
---

The crash_manager service does not export anything.

Channels
--------

The crash manager receives errors throught two channels:


* it listens on ``env.bus`` the event ``RPC_ERROR`` ;
* it listens on ``window`` the event ``error`` ;

RPC_ERROR event handling
------------------------

When an event ``RPC_ERROR`` is triggerd on the bus, the crash manager processes the
``RPCError`` in the following way:


* 
  look if the error's ``type`` is ``server`` ;

* 
  if this is the case, the optional error's ``name`` indicates which `dialog class <./dialog_manager.md#api>`_
  (from the registry ``errorDialogs`` ) should be used to display the error details.
  If the error is unnamed or no `dialog class] <./dialog_manager.md#api>`_ corresponds to its name, the class
  ``ErrorDialog`` is used by default.

* 
  The `dialog class <./dialog_manager.md#api>`_ is instantiated with one prop: the error itself.

This is how a ``UserError`` , ``AccessError``... or a custom server error is handled.

ERROR event handlling
---------------------

When an event ``error`` is triggered on window, the crash manager processes the ``ErrorEvent``
received in the following way:


* 
  if some information on the file name where the error occurs, the error stack... is available
  an ``ErrorDialog`` is displayed showing that information.

* 
  if such information is not available, an ``ErrorDialog`` is also displayed but with a generic message.

This is how client errors are treated.