kwik-e-mon

Monitor one-off tasks on your servers using Redis.

Installation

npm install -g kwikemon

Usage

$ kwikemond &
$ curl -s localhost/nginx_status | grep Active | kwikemon nginx-connections
$ curl localhost:1111/nignx-connections
Active connections: 316
$ kwikemon foo bar
$ curl localhost:1111/
foo: bar
nginx-connections: Active connections: 316

Here's how it works:

• call kwikemon thing status to set the text for the monitor named "thing"
• fire up the server, kwikemond, that serves up these monitors in a big list or individually

Alternatively:

• continuously pipe data to kwikemon <name of thing you are watching> on stdin
• every time a full line of text is received on stdin it becomes the new status for

To see everything kwikemon can do run it without arguments.

# or with -h or --help
$ kwikemon

This is very much a work in progress.

API

You can use kwikemon as a library.

var kwikemon = require('kiwkemon');

kwikemon.set('foo', 'bar', function(err) {
  kwikemon.fetch('foo', function(err, text) {
    console.log('foo = ' + text);
  });
});

kwikemon.fetchAll(function(err, monitors) {
  Object.keys(monitors).forEach(function (name) {
    console.log(name + ' = ' + monitors[name]);
  });
});

Monitors expire 1 day after the last time they were set by default. You can pass in any ttl you want though.

// never expire
kwikemon.set('foo', 'bar', { ttl: 0 });

Protocol

All kwikemon does is shove things into Redis in a standard way and read them out later.

A monitor named nginx stores its data in the hash kwikemon:monitor:nginx. Hash fields are:

• text
• created
• modified
• updates

The list of all monitors is a set stored at kwikemon:monitors.

List

This is when you should clean out expired entries.

names = redis.smembers("kwikemon:monitors")
monitors = {}
for name in names:
    if redis.exists("kwikemon:monitor:$name"):
        monitors[name] = redis.hget("kwikemon:monitor:$name", "text")
return monitors

Read

redis.hgetall("kwikemon:monitor:nginx")

Update

exists = redis.exists("kwikemon:monitor:nginx")
if exists:
    redis.hmset("kwikemon:monitor:nginx", {
        text: "Active connections: 583"
        modified: 1370668341943
    })
    redis.hincrby("kwikemon:monitor:nginx", "updates", 1)
else:
    redis.hmset("kwikemon:monitor:nginx", {
        text: "Active connections: 316"
        updates: 1
        created: 1370668301943
        modified: 1370668301943
    })
redis.sadd("kwikemon:monitors", "nginx")
# optional
redis.expire("kwikemon:monitor:nginx", <ttl>)

Delete

redis.del("kwikemon:monitor:nginx")
redis.srem("kwikemon:monitors", "nginx")

License

Copyright 2013 Sami Samhuri [email protected]

MIT license