Uptime Event Emitter
An uptime event emitter for http and tcp servers.
Installation
npm install ping-monitor
Documentation
How to use
const Monitor = require('ping-monitor');
const myWebsite = new Monitor(options);
myWebsite.on(event, function(response, state) {
// Do something with the response
});
Alternatively, you can subscribe to the Monitor's events through a notification channel. Click to see some demo nofitication channels.
const Monitor = require('ping-monitor');
const SlackChannel = require('@ping-monitor/slack');
const EmailChannel = require('@ping-monitor/email');
const myWebsite = new Monitor(options);
const slacker = new SlackChannel({...config});
const mailer = new EmailChannel({...config});
myWebsite.addNotificationChannel(slacker);
myWebsite.addNotificationChannel(mailer);
Methods
stop
- stop an active monitorrestart
- stop and start an active monitoraddNotificationChannel
(oraddChannel
) - adds a notification channel that subscribes to the monitor's events
Options
address
- Server address to be monitoredprotocol
- (defaults tohttp
) request protocol (http/s, tcp, udp)port
- Server port (optional).interval
(defaults to 15) - time interval for polling requests.httpOptions
- allows you to define your http/s request with more control. A full list of the options can be found here: https://nodejs.org/api/http.html#http_http_request_url_options_callbackexpect
{ statusCode , contentSearch } - allows you define what kind of a response you expect from your endpoint.statusCode
defines the expected http response status code.contentSearch
defines a substring to be expected from the response body.
config
{ intervalUnits } - configuration for your Monitor, currently supports one property,intervalUnits
.intervalUnits
specifies which to time unit you want your Monitor to use. There are 4 options,milliseconds
,seconds
,minutes
(default), andhours
.ignoreSSL
- ignore broken/expired certificatesup
- All is good server is up.down
- Not good, server is down.stop
- Fired when the monitor has stopped.error
- Fired when there's an errortimeout
- Fired when the http request times outrestored
- Fired server is up after being downobject.website
(deprecated) - website being monitored .object.address
- server addressobject.port
- server portobject.time
- (aka responseTime) request response timeobject.responseMessage
- http response code messageobject.responseTime
- response time in millisecondsobject.httpResponse
- native http/s response objectobject.id
null
- monitor id, useful when persistence.object.title
null
- monitor label for humans.object.isUp
true
- flag to indicate if monitored server is up or down.object.created_at
<Date.now()> - monitor creation date.object.isUp
true
- previous uptime status of the monitor.object.port
null
- server port.object.totalRequests
0
- total requests made.object.totalDownTimes
0
- total number of downtimes.object.lastDownTime
<Date.now()> - time of last downtime.object.lastRequest
<Date.now()> - time of last request.object.interval
5
- polling interval in minutesobject.website
null
- (deprecated) website being monitored.object.address
null
- server address being monitored.object.port
null
- server port.object.paused
false
- monitor paused flagobject.httpOptions
- monitor httpOptions optionsWebsite Example
'use strict'; const Monitor = require('ping-monitor'); const myMonitor = new Monitor({ address: 'http://www.ragingflame.co.za', title: 'Raging Flame', interval: 10 // minutes //protocol: 'http' }); myMonitor.on('up', function (res, state) { console.log('Yay!! ' + state.address + ' is up.'); }); myMonitor.on('down', function (res, state) { console.log('Oh Snap!! ' + state.address + ' is down! ' + state.statusMessage); }); myMonitor.on('restored', function (res, state) { console.log(state.address + ' has been restore'); }); myMonitor.on('stop', function (res, state) { console.log(state.address + ' monitor has stopped.'); }); myMonitor.on('timeout', function (error, res) { console.log(error); }); myMonitor.on('error', function (error) { console.log(error); });
TCP Example
'use strict'; const Monitor = require('ping-monitor'); const myMonitor = new Monitor({ address: '162.13.124.139', port: 8080, interval: 5, // minutes protocol: 'tcp' }); myMonitor.on('up', function (res, state) { console.log('Yay!! ' + state.address + ':' + state.port + ' is up.'); }); myMonitor.on('down', function (res, state) { console.log('Oh Snap!! ' + state.address + ':' + state.port + ' is down! '); }); myMonitor.on('restored', function (res, state) { console.log('Yay!! ' + state.address + ':' + state.port + ' has been restored! '); }); myMonitor.on('stop', function (res, state) { console.log(state.address + ' monitor has stopped.'); }); myMonitor.on('error', function (error, res) { console.log(error); }); myMonitor.on('timeout', function (error, res) { console.log(error); });
UDP Example
'use strict'; const Monitor = require('ping-monitor'); const myMonitor = new Monitor({ address: '32.13.124.139', port: 8080, interval: 5, protocol: 'udp' }); myMonitor.on('up', function (res, state) { console.log('Yay!! ' + state.address + ':' + state.port + ' is up.'); }); myMonitor.on('down', function (res, state) { console.log('Oh Snap!! ' + state.address + ':' + state.port + ' is down! '); }); myMonitor.on('restored', function (res, state) { console.log('Yay!! ' + state.address + ':' + state.port + ' has been restored! '); }); myMonitor.on('stop', function (res, state) { console.log(state.address + ' monitor has stopped.'); }); myMonitor.on('error', function (error, res) { console.log(error); }); myMonitor.on('timeout', function (error, res) { console.log(error); });
Change log
v0.8.0
Changes
- Added
protocol
property to the Monitor Options object - Added support for UDP servers. To monitor a UDP server, set the
protocol
property toudp
- Added the
restored
event which is emitted once when a server is up after beign down - Depracated
website
property on the Monitor Options object. Only useaddress
- Refactored some code
const ping = new Monitor({ address: '34.22.237.1', port: 1234, interval: 10, protocol: 'udp', }); ping.on('up', function (res, state) { console.log('Yay!! Service is up'); }); ping.on('down', function (res, state) { console.log(':( Service is down!'); }); ping.on('restored', function (res, state) { console.log('Yay!! Service has been restored'); }); ping.on('error', function (error, res) { console.error(error); });
v0.7.0
Changes
- Dependencies update.
- Added
addNotificationChannel
method to Monitor. - Added
addChannel
method to Monitor. This method is an alias of theaddNotificationChannel
method.
/*** * Channel class * methods: up, down, stop, error, timeout * properties: name ***/ class Logger { constructor(config = {}) { // do something with the config } name = 'logger'; up(res, state) { console.log(`#${this.name}: ${res.address} is up`); } down(res, state) { console.log(`#${this.name}: ${res.address} is down`); } stop(res, state) { console.log(`#${this.name}: ${res.address} monitor stopped`); } error(error, res, state) { console.log(`#${this.name}: ${res.address} monitor returned an error`); } timeout(error, res, state) { console.log(`#${this.name}: ${res.address} timed out`); } restored(error, res, state) { console.log(`#${this.name}: ${res.address} has been restored`); } } const ping = new Monitor({ address: 'https://google.com', interval: 30, protocol: 'http', config: { intervalUnits: 'seconds', } }); const logger = new Logger(); ping.addNotificationChannel(logger); // you can multiple notification channels // ping.addNotificationChannel(mailer) // ping.addNotificationChannel(slack)
v0.6.1
Changes
- Added auto id generation opt-out
let ping = new Monitor({ address: 'https://google.com', interval: 5, protocol: 'http', config: { intervalUnits: 'minutes', generateId: false // defaults is true } }); ping.on('up', function (res, state) { //state.id === null console.log('Yay!! Google is up'); }); ping.on('error', function (error, res) { console.error(error); });
v0.6.0
Changes
- Code refactoring
- Removed
active
from props (redundant) - Removed
host
from props (not used) - Added
ignoreSSL
to support websites with expired certificates
let ping = new Monitor({ address: 'https://wrong.host.badssl.com', interval: 1, protocol: 'http', config: { intervalUnits: 'minutes' // seconds, milliseconds, minutes {default}, hours }, ignoreSSL: true }); ping.on('up', function (res, state) { console.log('Yay!! Service is up'); }); ping.on('error', function (error, res) { console.error(error); });
v0.5.2
Changes
- Added support for configuring interval units
let ping = new Monitor({ address: 'https://webservice.com', interval: 1, protocol: 'http', config: { intervalUnits: 'minutes' } }); ping.on('up', function (res, state) { console.log('Yay!! Service is up'); }); ping.on('error', function (error, res) { console.error(error); });
v0.5.1
Changes
- Added Support for content search in HTTP/HTTPS - courtesy of @pbombnz
let ping = new Monitor({ address: 'https://ecommorce-shop.com/playstation5', interval: 1, protocol: 'http', expect: { contentSearch: 'In stock' } }); ping.on('up', function (res, state) { console.log('Yay!! Content cantains the phrase "In stock"'); }); ping.on('error', function (error, res) { console.error(error); });
v0.5.0
Changes
- Added
timeout
event to Monitor instance. This event is passed from the htt/s module.
myMonitor.on('timeout', function (error, res) { console.log(error); }); // also make sure that you are handling the error event myMonitor.on('error', function (error, res) { console.log(error); });
- Dependencies update
Please note: When the
timeout
event is fired, it is followed by theerror
event which is created when we manually abort the http request.v0.4.4
Dependencies update
v0.4.3
Changes
- Added the native http/s response object in the
Monitor
response object - Added Post support in your Monitor instances.
You can now include a body in your
httpOptions
:// http Post const myApi = new Monitor({ address: 'http://api.ragingflame.co.za', title: 'Raging Flame', interval: 10 // minutes protocol: 'http', // new options httpOptions: { path: '/users', method: 'post', query: { type: 'customer', }, body: { name: 'Que', email: '[email protected]' } }, expect: { statusCode: 200 } }); myApi.on('up', function (res, state) { /* response { responseTime <Integer> milliseconds responseMessage <String> response code message address <String> url being monitored. address <String> server address being monitored port <Integer> httpResponse <Object> native http/s response object } state { created_at <Date.now()> isUp <Boolean> port: <Integer> totalRequests <Integer> lastDownTime <Date.now()> lastRequest <Date.now()> interval <Integer> } */ });
v0.4.2
Changes
Added some utility methods used when updating a monitor and added immediate ping on monitor creation.
- Added
pause
method to Monitor. - Added
unpause
method to Monitor.
Tip: See options section to learn how they work.
v0.4.1
Changes
Changes in v0.4.1 give you more control to define your http requests and what response to expect.
- Added
httpOptions
prop to Monitor instance options. - Added
expect
prop for naming your your monitor.
Tip: See options section to learn how they work.
v0.4.0
Changes
Most of the changes introduced in this version were introduced to support database persistence.
- Added
id
prop, useful when you add database persistence. - Added
title
prop for naming your your monitor. - Added
active
prop to flag if monitoring is active. - Added
totalDownTimes
prop for keeping record of total downtimes. - Added
isUp
prop to indicate if monitored server is up or down. - Added
website
,address
,totalDownTimes
,active
,active
props to the emittedstate
object - Added eslinting (2015) and cleaned up the code a bit
- *breaking change: * the
stop
event now takes a callback that accepts 2 arguments,response
&&state
(same as theup
anddown
events).
v0.3.1
New Feature
-
Added a
state
object in the response that returns useful monitoring data -
State
object
const Monitor = require('ping-monitor'); const myMonitor = new Monitor(options); myMonitor.on(event, function(response, state) { /* response {...} state { created_at <Date.now()> isUp <Boolean> port: <Integer> totalRequests <Integer> lastDownTime <Date.now()> lastRequest <Date.now()> interval <Integer> } */ });
Changes made
- The event handler now accepts to arguments
response
andstate
, please see above examples.
v0.3.0
- Brought back
error
event - required for handling module usage related errors - Added
responseTime
to the response object - Added support for tcp servers
v0.2.0
- Code cleanup and upgrade to ES6
- Removed the
error
event - now being handled internally - Bug fixed: Unreachable resource not handled #9
Testing
npm test
License
(MIT License)
Copyright (c) 2013 - 2018 Qawelesizwe Mlilo [email protected]
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the 'Software'), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
- Added
Expect Object
expect {
statusCode: Integer, // http status codes
contentSearch: String
}
Config Object
config {
intervalUnits: String
}
// http Get
const myApi = new Monitor({
address: 'https://api.ragingflame.co.za',
title: 'Raging Flame',
interval: 5,
protocol: 'http', // http/s, tcp, udp
config: {
intervalUnits: 'minutes' // seconds, milliseconds, minutes {default}, hours
},
httpOptions: {
path: '/users',
method: 'get',
query: {
id: 3
}
},
expect: {
statusCode: 200
}
});
// http Post
const myApi = new Monitor({
address: 'http://api.ragingflame.co.za',
title: 'Raging Flame',
interval: 10,
protocol: 'http',
config: {
intervalUnits: 'minutes' // seconds, milliseconds, minutes {default}, hours
},
httpOptions: {
path: '/users',
method: 'post',
query: {
first_name: 'Que',
last_name: 'Fire'
},
body: {content:'Hello World!'}
},
expect: {
statusCode: 200
}
});