Slogged

socket.io logger middleware inspired by koa-logger

What is it?

Slogged is a basic logger middleware for socket.io that modifies the Socket class to output colorful logging to display information about client events, acks, emits, and errors. For the appearance it takes koa-logger as an inspiration.

Usage

$ npm install slogged

Then in your io.js (or wherever you're instantiating socket.io),

const io = require('socket.io')()
const slogger = require('slogged')
 
io.use(slogger())
 
io.on('connection', (socket) => {
  // ...
})

Types of logs

There are essentially four different types of logs: client events, emit events, acks, and errors.

Client events use <--, emit events use >>>, acks and errors both use --> as those are sent back to the originating client.

Acks and errors also report the overall time taken from the time the server received the packet to when the ack or error is sent back to the client. In addition, the overall connection time for the client is reported on disconnect events.

By default, payloads (both from client events and emits), acks, and error callstacks are included in the logs, but there is an option to disregard this data in the logs. See below.

For emits, if the broadcast flag is added, then the log will also add the client id that initiated the emit.

Finally, an important note about using acks and error logs is that the logging assumes you are using a standard Connect-like signature, with an error as the first argument, followed by the data to ack. If the first argument is not null then slogged will log it as an error. This is how it knows to log an error instead of a successful ack, since under the hood they are both triggered in the socket event's ack.

ack(null, { success: true }) // CORRECT! Will be logged as an OK ack
ack({ success: true }) // WRONG! Will be logged as an ERROR
ack(new Error(), null) // CORRECT! Will be logged as an ERROR

Make sense?

Options

Currently there are two options,

{
  minimal: false, // Set to true to ignore payloads, ack data, and error call stacks
  boring: false // Set to true to log plain jane, uncolorized text
}

Examples

With minimal === false

[socket.io] <-- connection Rquzt8syTkGjMZzyAAAB
[socket.io] <-- join Rquzt8syTkGjMZzyAAAB "[e-mail]"
[socket.io] <-- join Rquzt8syTkGjMZzyAAAB "1b9ie86u62"
[socket.io] <-- update-user Rquzt8syTkGjMZzyAAAB {"username":"[e-mail]","body":{"currentList":"1b9ie86u62"}}
[socket.io] >>> updated [e-mail] broadcast by Rquzt8syTkGjMZzyAAAB {"_id":"58c5658f0a3d0025673bdf89","darkmode":true,"username":"[e-mail]","currentList":"1b9ie86u62"}
[socket.io] --> update-user Rquzt8syTkGjMZzyAAAB OK 12ms {"_id":"58c5658f0a3d0025673bdf89","darkmode":true,"username":"[e-mail]","currentList":"1b9ie86u62"}
[socket.io] <-- create-item Rquzt8syTkGjMZzyAAAB {"listid":"1b9ie86u62","item":{"_id":"b2oo811us1","item":"Do something","createdBy":"[e-mail]","complete":false,"dateCreated":"2017-06-21T14:21:29.182Z","dueDate":null,"dateCompleted":null,"completedBy":"","notes":"","_dueDateDifference":null,"_deleting":false,"_detailsToggled":false},"username":"[e-mail]"}
[socket.io] --> create-item Rquzt8syTkGjMZzyAAAB ERR 2ms ERRROOOOOR
Error: ERRROOOOOR
    at Object.create (/Users/patrick/Projects/taskmastr/routes/items.js:10:11)
    at Socket.socket.on (/Users/patrick/Projects/taskmastr/io.js:96:18)
    at emitTwo (events.js:125:13)
    at Socket.emit (events.js:213:7)
    at /Users/patrick/Projects/taskmastr/node_modules/socket.io/lib/socket.js:514:12
    at _combinedTickCallback (internal/process/next_tick.js:95:7)
    at process._tickCallback (internal/process/next_tick.js:161:9)

With minimal === true

[socket.io] <-- connection Rquzt8syTkGjMZzyAAAB
[socket.io] <-- join Rquzt8syTkGjMZzyAAAB "[e-mail]"
[socket.io] <-- join Rquzt8syTkGjMZzyAAAB "1b9ie86u62"
[socket.io] <-- update-user Rquzt8syTkGjMZzyAAAB 
[socket.io] >>> updated [e-mail] broadcast by Rquzt8syTkGjMZzyAAAB
[socket.io] --> update-user Rquzt8syTkGjMZzyAAAB OK 12ms 
[socket.io] <-- create-item Rquzt8syTkGjMZzyAAAB
[socket.io] --> create-item Rquzt8syTkGjMZzyAAAB ERR 2ms ERRROOOOOR

License

Slogged is freely distributable under the terms of the MIT license.