Nick nickknissen

Controlling the Brother P-Touch Cube label maker from a computer

The Brother PTP300BT label maker is intended to be controlled using the official Brother P-Touch Design & Print iOS/Android app. The app has arbitrary limits on what you can print (1 text object and up to 3 preset icons), so I thought it would be a fun challenge to reverse engineer the protocol to print whatever I wanted.

Python code at the bottom if you want to skip the fine details.

Process

Intitially I had a quick peek at the Android APK to see if there was any useful information inside. The code that handles the communication with the printer in Print&Design turned out to be a native library, but the app clearly prepares a bitmap image and passes it to this native library for printing. Bitmaps are definitely something we can work with.

README

This gist assumes you are migrating an existing site for www.example.com — ideally WordPress — to a new server — ideally Ubuntu Server 16.04 LTS — and wish to enable HTTP/2 (backwards compatibile with HTTP/1.1) with always-on HTTPS, caching, compression, and more. Although these instructions are geared towards WordPress, they should be trivially extensible to other PHP frameworks, other FastCGI backends, and even non-FastCGI backends (using proxy in lieu of fastcgi in the terminal Caddyfile stanza).

Quickstart: Use your own naked and canonical domain names instead of example.com and www.example.com and customize the Caddyfile and VCL provided in this gist to your preferences!

These instructions target Varnish Cache 4.1, PHP-FPM 7.0, and Caddy 0.10. (I'm using MariaDB 10.1 as well, but that's not relevant to this guide.)

Moving to ES6 from CoffeeScript

I fell in love with CoffeeScript a couple of years ago. Javascript has always seemed something of an interesting curiosity to me and I was happy to see the meteoric rise of Node.js, but coming from a background of Python I really preferred a cleaner syntax.

In any fast moving community it is inevitable that things will change, and so today we see a big shift toward ES6, the new version of Javascript. It incorporates a handful of the nicer features from CoffeeScript and is usable today through tools like Babel. Here are some of my thoughts and issues on moving away from CoffeeScript in favor of ES6.

While reading I suggest keeping open a tab to Babel's learning ES6 page. The examples there are great.

Punctuation

Holy punctuation, Batman! Say goodbye to your whitespace and hello to parenthesis, curly braces, and semicolons again. Even with the advanced ES6 syntax you'll find yourself writing a lot more punctuatio

	<?php

	declare(strict_types=1);

	namespace App\DataTransferObjects;

	use Carbon\CarbonImmutable;
	use Spatie\DataTransferObject\Caster;

	class CarbonImmutableCaster implements Caster

	# A Python script that decrypts the content of Kamstrup KEM file and imports meter files
	# to wmbusmeters' config folder.
	#
	# The KEM file is a (sometimes zipped) xml file that contains xml-encrypted data using
	# the xml-enc standard (http://www.w3.org/2001/04/xmlenc). The password needed to decrypt
	# the xml-encrypted data can either be the CustomerId or something else selected by the
	# person that has created the KEM file using Kamstrup software.
	#
	# This script takes the encrypted KEM file and decrypts its content (it automaticly detects
	# the zip archive and extracts the kem file from it). The result is a XML with a list of meters

	/* Helper buddy for removing async/await try/catch litter 🗑 */
	function O_o(promise) {
	return promise.then(data => {
	if (data instanceof Error) return [data]
	return [null, data]
	}).catch(err => [err])
	}

	/* Look ma, no try/catch */
	async function usageExample(params) {

	# Description: Boxstarter Script
	# Author: Jess Frazelle <jess@linux.com>
	# Last Updated: 2017-09-11
	#
	# Install boxstarter:
	# . { iwr -useb http://boxstarter.org/bootstrapper.ps1 } \| iex; get-boxstarter -Force
	#
	# You might need to set: Set-ExecutionPolicy RemoteSigned
	#
	# Run this boxstarter by calling the following from an elevated command-prompt:

	##################
	# Privacy Settings
	##################

	# Privacy: Let apps use my advertising ID: Disable
	Set-ItemProperty -Path HKCU:\SOFTWARE\Microsoft\Windows\CurrentVersion\AdvertisingInfo -Name Enabled -Type DWord -Value 0
	# To Restore:
	#Set-ItemProperty -Path HKCU:\SOFTWARE\Microsoft\Windows\CurrentVersion\AdvertisingInfo -Name Enabled -Type DWord -Value 1
	# Privacy: SmartScreen Filter for Store Apps: Disable
	Set-ItemProperty -Path HKCU:\SOFTWARE\Microsoft\Windows\CurrentVersion\AppHost -Name EnableWebContentEvaluation -Type DWord -Value 0

	// Implementation in ES6
	function pagination(c, m) {
	var current = c,
	last = m,
	delta = 2,
	left = current - delta,
	right = current + delta + 1,
	range = [],
	rangeWithDots = [],
	l;