Documentation on customization of error resopnse incorrect

[DonutEspresso]

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Bug Report

Example of how to customize errors in restify 5.x docs is incorrect.

Restify Version

Docs site for 5.x.

Node.js Version

All

Expected behaviour

On the server API page (http://restify.com/docs/server-api/), example shows

server.on('InternalServer', function(req, res, err, callback) {
    err.body = 'Sorry, an error occurred!';
    return callback();
});

But the returned value to client is still {}.

Actual behaviour

We should be asking folks to implement a custom toJSON in their error listeners instead:

server.on('restifyError', function(req, res, err, callback) {
    err.toJSON = function customToJSON() {
        return 'i just want a string';
    };
    return callback();
});

Cause

More details on restify/errors#72.

Are you willing and able to fix this?

Yes