PM2 Webhook Monitor

This is a pm2 module which monitors application processes and sends log messages of specified events, exceptions and errors.

At the first, I want to monitor my application and I want a program which can notify me on WeChat when my application crashes. But, for some reason, I have to implement this by a private webhook url. So this module is only works for me. If you want to use a public webhook url (e.g. WeChat webhook) or your own private url, you can fork this module and implement your own notify function in notifier.js. It's very easy.

Usage

You should install this module first:

pm2 install pm2-webhook-monitor

To get this module work, you need to tell it your webhook url:

pm2 set pm2-webhook-monitor:webhookUrl < https://www.webhook.com/notify.action >

And for my case, I use phone numbers to specify the people who will receive the notification. It could be set like this:

pm2 set pm2-webhook-monitor:phone "13000000000,13000000001"

Configuration

Here are the all configuration items and their default value.

{
  "webhookUrl"        : null,
  "log"               : false,
  "error"             : true,
  "kill"              : true,
  "exception"         : true,
  "restart"           : true,
  "reload"            : true,
  "delete"            : true,
  "stop"              : true,
  "restart overlimit" : true,
  "exit"              : false,
  "start"             : false,
  "online"            : false,
  "phone"             : null,
  "bufferMaxSecond"   : 5,
  "buffer"            : true
}

You can config them by using:

pm2 set pm2-webhook-monitor:<key> <value>

Message merge and postpone sending

When our application is executed in cluster mode, there will be many processes. And if we restart the application, every process will trigger a restart event and all the events will be notified to us. I think this is unnecessary and use a message queue to avoid this behaviour.

The message queue receives messages and merges the same event. Then it uses a scheduler to finish the notify task.

We can enable this by set:

pm2 set pm2-webhook-monitor:buffer true

And the bufferMaxSecond specifies how long should the monitor program buffer the messages. The default value is 5, which means the message queue waits at most 5 seconds while the first message is arrived. Once the waiting time is over the limit, the notify task is executed immediately.

Acknowledgements

• pm2-slack : This project inspired me to create this module, thanks to every one contributes to this project, thanks for their hard-working and open source spirit.

• sailor103 : This is one of my best friends, he introduced the pm2-slack project to me, and he often plays the duck role in my rubber duck debugging. Thanks for his time and love(just love between friends, I'm not a gay, but I'm not sure if he is a gay 😏 ).