Middleware functionality

[kritzware]

Issue for discussion about Bot middleware functionality and ideas.

Inspired by Express middleware functions.

Express implementation:

app.use(function (req, res, next) {
  console.log('Time:', Date.now())
  next()
})

Bot.use((chatter, send) => {
  // ... some sort of operation with the chatter object, or message string

  send() // Allows the message to be sent
})

In relation to this, the idea of custom Bot plugins would be cool e.g.

const TwitchBotCommands = require('twitch-bot-commands')

// The custom bot module
const commands = TwitchBotCommands("!", {
  "test": "command executed!",
  "tweet": async chatter => {
    const latestTweet = await someAsyncApiRequest(chatter.username)
    return `Latest tweet: ${latestTweet}`
  }
})

// Instantiate the module
Bot.module(commands)