@mayeaux
Correct me if I am wrong, but channelName, channel description and comment are only affected by these endpoints:

• POST /:channel/:media - comments
• POST /account/profile - ChannelName and channel description
  So I've added validation and sanitization to middleware of these endpoints.

Looks really good! I like the JSDocs usage I was planning to start that soon so I'm glad you got the ball rolling.

Quick question what's this for:
const express = require("express"); //JSDoc types only

Other than that I can merge this right away, thanks my friend!

Quick question what's this for:
const express = require("express"); //JSDoc types only

It's for better type inference. VSCode comes pre-bundled with Typescript which adds a lot of type info and tooltips and also infers types off JSDoc comments.

@BassOfBass : check the review:

this works for you? it throws an error for me

TypeError: req.sanitize(...).trim(...).escape is not a function
at exports.postSignup (/Users/anthony/Development/nodetube/controllers/backend/account.js:148:37)

@mayeaux Guess this version of validator can't into chaining.

@mayeaux please review again.

@mr-winson
The newest version works as collection of functions instead of middleware, so it will require complete rewrite of every req.assert() instance. But more importantly there should be a single source of truth in regards to validation constraints in the first place,