express-hot-shots

StatsD route monitoring middleware for
Connect/Express.
This middleware can be used either globally or on a per-route basis (preferred)
and sends status codes and response times to StatsD.

Forked from uber/express-statsd for usage in Spectrum.

Installation

`` bash
npm install express-hot-shots
`

Usage

An example of an express server with express-hot-shots:

` js
var express = require('express');
var statsd = require('express-hot-shots');
var app = express();

app.use(statsd());

app.get('/', function (req, res) {
res.send('Hello World!');
});

app.listen(3000);
`

By default, the middleware will send status_code and response_time stats
for all requests. For example, using the created server above and a request to
http://localhost:3000/, the following stats will be sent:

`
status_code.200:1|c
response_time:100|ms
`

$3

However, it's highly recommended that you set req.statsdKey which
will be used to namespace the stats. Be aware that stats will only be logged
once a response has been sent; this means that req.statsdKey can be
set even after the express-hot-shots middleware was added to the chain. Here's an
example of a server set up with a more specific key:

` js
var express = require('express');
var expressStatsd = require('express-hot-shots');
var app = express();

function statsd (path) {
return function (req, res, next) {
var method = req.method || 'unknown_method';
req.statsdKey = ['http', method.toLowerCase(), path].join('.');
next();
};
}

app.use(expressStatsd());

app.get('/', statsd('home'), function (req, res) {
res.send('Hello World!');
});

app.listen(3000);
`

A GET request to / on this server would produce the following stats:

`
http.get.home.status_code.200:1|c
http.get.home.response_time:100|ms
`

$3

You can set the tags of the metrics with the req.statsdTags property.

`JS

function statsd (path) {
return function (req, res, next) {
var method = req.method || 'unknown_method';
req.statsdKey = ['http', method.toLowerCase(), path].join('.');
req.statsdTags = {
server: process.env.SERVER_NAME,
}
next();
};
}
`

These will be sent with both the response time and status code metrics.

$3

This module also works with any http server

`js
var http = require('http');
var expressStatsd = require('express-hot-shots');

var monitorRequest = expressStatsd();

http.createServer(function (req, res) {
monitorRequest(req, res);

// do whatever you want, framework, library, router
res.end('hello world');
}).listen(3000);
`

Options

` js
expressStatsd(options);
`

- options Object - Container for settings
- client HotShots instance - a custom hot shots instance
- hotShots Object - The hotShots options if you don't want to provide your own instance
- requestKey String - The key on the req object at which to grab
the key for the statsd logs. Defaults to req.statsdKey`.