Uptime Event Emitter
An uptime event emitter for http and tcp servers.
Installation
npm install --save @hfsnetbr/boleto-utils
How to use
const Monitor = require('ping-monitor');
const myWebsite = new Monitor(options);
myWebsite.on(event, function(response, state) {
// Do something with the response
});
Options
-
website
- The url of the website to be monitored (required is monitoring a website). -
address
- Server address to be monitored (required if monitoring tcp server). -
port
- Server port (required if monitoring tcp server). -
interval
(defaults to 15) - time interval (in minutes) for polling requests.
New Options: v0.4.1
The new options give you more control to define your http endpoints.
-
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_callback -
expect
- allows you define what kind of a response you expect for your endpoint. At the moment expect accepts 1 prop (more to be added in future versions),statusCode
a http status code.
// http Get
const myApi = new Monitor({
website: 'http://api.ragingflame.co.za',
title: 'Raging Flame',
interval: 10 // minutes
// new options
httpOptions: {
path: '/users',
method: 'get',
query: {
id: 3
}
},
expect: {
statusCode: 200
}
});
// http Post
const myApi = new Monitor({
website: 'http://api.ragingflame.co.za',
title: 'Raging Flame',
interval: 10 // minutes
// new options
httpOptions: {
path: '/users',
method: 'post',
query: {
first_name: 'Que',
last_name: 'Fire'
},
body: 'Hello World!'
},
expect: {
statusCode: 200
}
});
Emitted Events
-
up
- All is good website is up. -
down
- Not good, website is down. -
stop
- Fired when the monitor has stopped. -
error
- Fired when there's an error -
timeout
- Fired when the http request times out
response object
-
object.website
- website being monitored. -
object.address
- server address being monitored. -
object.port
- server port. -
object.time
- (aka responseTime) request response time. -
object.responseMessage
- http response code message. -
object.responseTime
- response time in milliseconds. -
object.httpResponse
- native http/s response object.
state object
-
object.id
null
- monitor id, useful when persistence. -
object.title
null
- monitor label for humans. -
object.active
true
- flag to indicate if monitor is active. -
object.isUp
true
- flag to indicate if monitored server is up or down. -
object.created_at
<Date.now()> - monitor creation date. -
object.isUp
true
- current uptime status of the monitor. -
object.port
null
- server port. -
object.host
null
- server / website address. -
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 minutes -
object.website
null
- website being monitored. -
object.address
null
- server address being monitored. -
object.port
null
- server port.
Website Example
'use strict';
const Monitor = require('ping-monitor');
const myMonitor = new Monitor({
website: 'http://www.ragingflame.co.za',
title: 'Raging Flame',
interval: 10 // minutes
});
myMonitor.on('up', function (res, state) {
console.log('Yay!! ' + res.website + ' is up.');
});
myMonitor.on('down', function (res) {
console.log('Oh Snap!! ' + res.website + ' is down! ' + res.statusMessage);
});
myMonitor.on('stop', function (website) {
console.log(website + ' monitor has stopped.');
});
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
});
myMonitor.on('up', function (res, state) {
console.log('Yay!! ' + res.address + ':' + res.port + ' is up.');
});
myMonitor.on('down', function (res, state) {
console.log('Oh Snap!! ' + res.address + ':' + res.port + ' is down! ');
});
myMonitor.on('stop', function (res, state) {
console.log(res.address + ' monitor has stopped.');
});
myMonitor.on('error', function (error, res) {
console.log(error);
});
myMonitor.on('timeout', function (error, res) {
console.log(error);
});
Change log
v0.5.1
Changes
- Added Support for content search in HTTP/HTTPS - courtesy of @pbombnz
let ping = new Monitor({
website: 'https://ecommorce-shop.com/playstation5',
interval: 0.1,
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 the error
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({
website: 'http://api.ragingflame.co.za',
title: 'Raging Flame',
interval: 10 // minutes
// new options
httpOptions: {
path: '/users',
method: 'post',
query: {
first_name: 'Que',
last_name: 'Fire'
},
body: 'Hello World!'
},
expect: {
statusCode: 200
}
});
myApi.on('up', function (res, state) {
/*
response {
responseTime <Integer> milliseconds
responseMessage <String> response code message
website <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>
host <String>
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>
host <String>
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 qawemlilo@gmail.com
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.