System Watcher

Setup

1) Add NPM package

``shell
npm init
npm install --save sys-watcher
`

2) Create watcher.js with following code as an example

`javascript
const SysWatcher = require('sys-watcher');

let watcher = new SysWatcher();

watcher.start();
`

3) Create config.js with following code as an example

`javascript
module.exports =
{ caching: {
file3min: {
type: 'FileCache'
, settings: {
lifespan: '3 min'
}
}
, redis3min: {
type: 'RedisCache'
, settings: {
lifespan: '3 min'
}
}
}
, loggers: {
email: {
type: 'MailLogger'
, settings: {
recipients: [ '' ]
, sender: ''
}
, composing: {
format: 'text'
, hostInfo: true
, locationInSubject: true
, subject: 'Error report'
}
}
, slackChannel: {
type: 'SlackLogger'
, settings: {
kind: 'webhook'
, webHooks: [ '' ]
}
, composing: {
hostInfo: true
}
}
, slackDirect: {
type: 'SlackLogger'
, settings: {
kind: 'direct'
, token: ''
, recipients: [ '' ]
}
, composing: {
hostInfo: true
}
}
, telegram: {
type: 'TelegramLogger'
, settings: {
token: ''
, recipients: [ ]
}
, composing: {
hostInfo: true
}
}
, AWSFreeSpaceCloudWatch: {
type: 'AWSCloudWatchLogger'
, settings: {
metricName: 'FreeSpace'
, nameSpace: 'TESTING'
, units: 'Bytes'
, AWS: {
region: 'us-east-1'
, accessKeyId: ''
, secretAccessKey: ''
}
}
, composing: {
hostInfo: true
, locationInfo: true
}
}
}
, globals: {
location: ''
, onStart: {
composing: {
hostInfo: true
}
, loggers: [ 'email', 'slackDirect' ]
, cache: 'file3min'
}
, onError: {
loggers: [ 'slackChannel', 'telegram' ]
, composing: {
hostInfo: true
}
, cache: 'redis3min'
}
}
, watchers: {
freeSpaceWatcher: {
type: 'FreeSpaceWatcher'
, settings: {
path: '/'
, threshold: '1 Gb'
}
, loggers: [ 'email', 'slackDirect' ]
, scheduling: {
interval: '5 min'
}
}
, freeRAMWatcher: {
type: 'FreeRAMWatcher'
, settings: {
threshold: '16 Gb'
}
, loggers: [ 'email', 'slackDirect' ]
, scheduling: {
interval: '1 min'
}
}
, apacheErrorLog: {
type: 'FileWatcher'
, settings: {
path: [ '/var/log/httpd/error_log' ]
, rules: {
all: {
match: [ '([0-9]+[/][0-9]+[/][0-9]+ [0-9]+\:[0-9]+\:[0-9]+ \[error\] [0-9#]+\: [0-9*]+) (.+)' ]
, cacheKey: '$2'
}
}
}
, loggers: [ 'email', 'slackDirect' ]
, cache: 'redis3min'
}
, CMWatcher: {
type: 'ConfigurationWatcher'
, settings: {
rules:[
{ cmd: 'node -v', check: '(8|10).16.(0|1|2)' }
]
}
, scheduling: {
interval: '60 minutes'
}
, loggers: [ 'email', 'slackDirect' ]
, cache: 'redis'
}
}
};
`

4) Run the watcher

`shell
node watcher.js start
`

Run using pm2 http://pm2.keymetrics.io.

The best way to make sure watcher is always up and running is to use pm2.

1) Create ecosystem.config.yml using following code as an example:

`yaml
apps:
- script : ./watcher.js
name : 'Watcher'
cwd : '/usr/local/node/sys-watcher/'
args : 'start --config config.js'
treekill : false
watch : true
watch_delay : 1000
ignore_watch:
- .git
- node_modules
error_file : '/var/log/node/sys-watcher.err'
out_file : '/var/log/node/sys-watcher.log'
combine_logs: true
max_memory_restart: '200M'
`

2) Run watcher through pm2

`shell
pm2 start
`

3) Check it's running using

`shell
pm2 ls
`

4) Check logs using

`shell
pm2 logs
``

Components

$3

- AWSSQSWatcher
- ConfigurationWatcher
- CronWatcher
- DirectoryWatcher
- FileWatcher
- FreeRAMWatcher
- FreeSpaceWatcher
- GitHubWebHookWatcher
- HTTPWatcher
- MailQueueWatcher
- MySQLWatcher
- ProcessWatcher
- RabbitMQWatcher
- SSLCertificateWatcher
- WebWatcher

$3

- FileCache
- RedisCache

$3

- AWSCloudWatchLogger
- ConsoleLogger
- MailLogger
- RabbitMQLogger
- SlackLogger
- TelegramLogger