500-pagelet

Default 500 Pagelet used if anything fails in BigPipe

Usage no npm install needed!

<script type="module">
  import 00Pagelet from 'https://cdn.skypack.dev/500-pagelet';
</script>

README

500 Pagelet

Version npmBuild StatusDependenciesCoverage Status

This Pagelet is responsible for displaying server errors. By default the 500 Pagelet is provided with BigPipe. However, if you need a custom 500 you can extend this Pagelet. For example to change the default view.

Installation

The 500 Pagelet is distributed through the node package manager (npm).

npm install --save 500-pagelet

Support

Got stuck? Or can't wrap your head around a concept or just want some feedback, we got a dedicated IRC channel for that on Freenode:

  • IRC Server: irc.freenode.net
  • IRC Room: #bigpipe

Still stuck? Create an issue. Every question you have is a bug in our documentation and that should be corrected. So please, don't hesitate to create issues, many of them.

Example

In this example the 500 Pagelet is extended with a custom view. BigPipe will automatically discover this extended version if it is provided to BigPipe alongside the other pagelets. Note that the enviroment variable can be overruled to manage the data that is displayed.

'use strict';

//
// Extend the 500 Pagelet with a custom view.
//
var Fivehundred = require('500-pagelet').extend({
  view: '/path/to/my/custom-view.html',  // your custom layout
  env: 'development'                     // defaults to process.env.NODE_ENV
});

//
// Initialise BigPipe server.
//
var pipe = require('bigpipe').createServer(2000, {
  pagelets: [ Fivehundred, ... ]
});

API

The following methods are available on the 500 Pagelet instance. Most are only used internally. There is rarely a reason to call these methods.

new Fivehundred()

public, returns Pagelet.

The 500 constructor expects several options to be provided, these include: req, res and pipe. The last option is a reference to the BigPipe instance, mainly to ensure the same Temper instance is re-used. All code examples assume your file is setup as:

'use strict';

var Fivehundred = require('500-pagelet');
  , fivehundred = new Fivehundred({ options }, new Error('failure'));

Bootstrap.get()

private, returns Pagelet.

Extracts the data from the provided Error to render the template. If the environment is production the Error.stack will not be provided to the template.

fivehundred.get(function render(error, data) {
  // provide data to pagelet.render
});

Debugging

The library makes use the diagnostics module from Pagelet. To display the 500 Pagelet specific debug messages, supply the following before running the program or

DEBUG=pagelet:500 node ...

Testing

Tests are automatically run on Travis CI to ensure that everything is functioning as intended. For local development we automatically install a pre-commit hook that runs the npm test command every time you commit changes. This ensures that we don't push any broken code in to this project.

To run tests locally, make sure the development dependencies are installed.

npm test
npm run coverage

License

500-pagelet is released under MIT.