restify 5.0 is finally here! And a great big thank you to all of our contributors. 5.x fixes a ton of bugs, adds some new features, and introduces some breaking changes. This guide helps make sense of all the major changes that have happened since the last 4.x release. A more detailed change log can be found in CHANGES.md.
Plugins, which used to available on the restify.plugins namespace and the
restify.pre namespace, now live in their own
repository and are published
independently on npm. This gives us a
lot more flexibility to make progress in both repos independently. All the
existing plugins are available in the repo, minus CORS. We'll touch on CORS a
little more below.
Errors, which used to be available on the restify.errors namespace, now live
in their own repository and are published
independently on npm.
restify-errors can be used independently of restify in any of your other
projects for customizable error classes and chained errors.
All restify clients have been broken out into their own repository, and are published independently on npm.
restify now emits a generic error event. This error event will be fired for all
errors passed to next(). If you have specific listeners attached for a class
of error, the most specific one will be fired first, with the generic one being
fired last.
// in some route, create a 500
server.get('/', function(req, res, next) {
return next(new InternalServerError('oh noes!'));
// this will hit the InternalServerError FIRST, allowing you to handle it some fashion,
// before firing restifyError event. the semantics of the generic handler means it should
// always be fired, but doesn't mean we shouldn't allow you to handle it first within
// the error handler they care about. this is only possible if we fire events in serial.
});
// handle 500s
server.on('InternalServer', function(req, res, err, cb) {
// this event is fired first. you can annotate errors here by saying
// err.handled = true, because we must ALWAYS fire the generic handler after.
err.handled = true;
return cb();
});
// generic error handler
server.on('restifyError', function(req, res, err, cb) {
// this event is fired last. do some generic metrics/logging
if (!err.handled) {
// do something
}
return cb();
});restify now emits a redirect event when res.redirect() is used. The event is
fired with the new location of the redirect.
SERVER.on('redirect', function (newLocation) {
// newLocation is the new url we redirected to.
});restify's error events for these four types of errors have now been normalized to act like other error events. Previously, listening to these events would require you to send a response. It has now been normalized to work like the other error events:
server.on('NotFound', function(req, res, err, cb) {
// do some logging or metrics collection here. if you want to send a custom
// response, you can do so here by setting the response on the body of the
// error object.
err.body = 'whoops! can't find your stuff!'; // the body of the error becomes the response
return cb();
});CORS has been removed from restify core. That means the existing CORS plugin is no longer compatible with 5.x. A new CORS plugin is currently in development in the restify-plugins repo. It's a brand new rewrite of CORS and aims to address all the shortcomings of the previous plugin. All that's left is to get some tests in to verify the behavior.
If you're using CORS, we'd love to get your help testing this thing and getting it out the door!
Strict routing is now supported via the strictRouting option. This allows
differentiation of routes with trailing slashes. The default value is false,
which mimics the behavior in 4.x which is to strip trailing slashes.
var server = restify.createServer({
strictRouting: true
});
// these two routes are distinct with strictRouting option
server.get('/foo/', function(req, res, next) { });
server.get('/foo', function(req, res, next) { });restify has a concept of formatters, where each formatter is executed to format
a the content of a response before sending it out. A new method,
res.sendRaw(), has been added which allows bypassing of the formatters in
scenarios where you have preformatted content (pre-gzipped, pre-JSON
stringified, etc.). sendRaw has the same signature as send.
Previous versions of restify had some undocumented exports on the main object. These have been removed as of 5.x. These include:
restify.CORS- due to removal of CORS from corerestify.httpDate- undocumentedrestify.realizeUrl- undocumented
To help reduce unintentional exposure of errors to the client, restify no longer does special JSON serialization for Error objects. For example:
server.get('/sendErr', function(req, res, next) {
res.send(new Error('where is my msg?'));
return next();
});
server.get('/nextErr', function(req, res, next) {
return next(new Error('where is my msg?'));
});$ curl -is localhost:8080/sendErr
HTTP/1.1 410 Gone
Content-Type: application/json
Content-Length: 37
Date: Fri, 03 Jun 2016 20:17:48 GMT
Connection: keep-alive
{}
$ curl -is localhost:8080/nextErr
HTTP/1.1 410 Gone
Content-Type: application/json
Content-Length: 37
Date: Fri, 03 Jun 2016 20:17:48 GMT
Connection: keep-alive
{}The response is an empty object because JSON.stringify(err) returns an empty
object. In order to get properly serialized Errors, the preferred method is to
use restify-errors, which will have defined toJSON methods. Alternatively,
if you have custom Error classes, you can define a toJSON method which is
invoked when your Error is being stringified. If you have many custom error
types, consider using restify-errors to help you create and manage them easily.
Lastly, you can use restify-errors to opt-in to automatic toJSON
serialization:
var errs = require('restify-errors');
server.get('/', function(req, res, next) {
res.send(new errs.GoneError('gone girl'));
return next();
});$ curl -is localhost:8080/
HTTP/1.1 410 Gone
Content-Type: application/json
Content-Length: 37
Date: Fri, 03 Jun 2016 20:17:48 GMT
Connection: keep-alive
{"code":"Gone","message":"gone girl"}Restify now supports both sync and async formatters. In 4.x, all formatters had an async signature despite not being async. For example, the text formatter in 4.x might have looked like this:
function formatText(req, res, body, cb) {
return cb(null, body.toString());
}This caused a scenario where formatting could potentially fail, but the handler
chain would continue on. To address this gap, as of 5.x, any formatters that
are async require a callback to be passed into res.send(). For example,
imagine this async formatter:
function specialFormat(req, res, body, cb) {
return asyncSerializer.format(body, cb);
}
server.get('/', function(req, res, next) {
res.send('hello world', function(err) {
if (err) {
res.end('some other backup content when formatting fails');
}
return next();
});
});
server.get('/', function(req, res, next) {
// alternatively, you can pass the error to next, which will render the
// error to the client.
res.send('hello world', next);
});This way we are able to block the handler chain from moving on when an async formatter fails. If you have any custom formatters, migrating from 4.x will require you to change the formatter to be sync. Imagine the previous text formatter changed to sync. Notice that the signature no longer takes a callback. This hints to restify that the formatter is sync:
function formatText(req, res, body) {
return body.toString();
}Thus, if your formatter takes 4 parameters (i.e., takes a callback),
invocations of res.send() must take a callback, or else restify will throw.
The following are still currently supported, but are on life support and may be removed in future versions. Usage of these features will cause restify to spit out deprecation warnings in the logs.
In 4.x, restify utilized domains by default. Any errors captured by the domain
could be handled to via the server.on('uncaughtException', ...) event.
However, it was not immediately obvious that this behavior was happening by
default, and many errors often went unhandled or unnoticed by end users.
With domains being deprecated, we've opted to turn domains off by default. If
you want to use domains, you can turn them back on via the
handleUncaughtExceptions option when you create the server:
var server = restify.createServer({
handleUncaughtExceptions: true
});The next.ifError() feature leveraged domains under the hood. This feature is
also deprecated, and will only be available to you if the
handleUncaughtExceptions flag is set to true.