exceptions.html

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<div class="content">
  <h1>Exceptions</h1>

  <p>Tyranid provides the following exceptions:</p>

  <table>
    <thead>
      <tr>
        <th>Exception<th>Usage<th>HTTP Code<a href="#httpCode"><super>*</super></a><th>Example Reporting
    <tbody>
      <tr>
        <td><a href="appError">AppError</a><td>Use for any sort of application-level exception that is unexpected.<td>500<td>Bugsnag
      <tr>
        <td><a href="eventCancelError">EventCancelError</a><td>Generally should not be used manually, sent when an event handler calls "preventDefault()".<td>Not rethrown
          <td>Not reported since this indicates that an event should not be propagated for non-error reasons.
      <tr>
        <td><a href="secureError">SecureError</a><td>Use for any sort of security violations like access denied.<td>403<td>Security log
      <tr>
        <td><a href="userError">UserError</a><td>Use for any sort of user errors where the problem lies with bad input or data from the user.<td>400
          <td>Not logged, reported inline in the user interface (for example, below form fields, or as toast messages, depending on the context)
  </table>

  <div id="httpCode"><super>*</super> The HTTP codes can be overridden in the <a href="tyr#config"><u>Tyr.config()</u></a> call.</div>

  <p>Exceptions that have an HTTP Code defined indicate that the exception will be rethrown in the <i>calling context</i>.  For example, if a 
    call is made in the web browser to a server via a <a href="services">service</a>, and the service throws a rethrowable exception, then the exception thrown on
    the server will be caught, serialized, sent along the HTTP, and then reified and rethrown on the client.</p>

  <p>Exceptions thrown inside event handlers will also be rethrown in the calling context.</p>