Science Fare

I was surprised to see that Xcode does not make it easy to build all the various icon files for AppIcons for Mac OS and IOS. A few tools have been whipped together, but I’m not a fan of needing to install a whole new GUI app just to solve a simple problem. I’m also not a huge proponent of python, but it’s one of the scripting languages that natively supports JSON — which is part of how Apple’s implemented .xcassets (look inside you’ll see a file called Contents.json). So here is my solution — you’ll need to customize it for your own project. This particular project has two different AppIcon.appiconset entries in the xcassets file.

Note that this script re-writes the Contents.json file, to normalize the file naming. By default if you drag-and-drop files into Xcode it just adds -1 and -2 etc.. to the name, which is lame.

Whenever you update the icon (hardcoded here as a file called ‘icon.pdf’) re-run this script and the icon for you Mac and/or iOS app will update!

import re
import json
from subprocess import call
from pprint import pprint

for iconset in ['Design Show Server/Images.xcassets/AppIcon.appiconset', 'Design Show/Images.xcassets/AppIcon.appiconset']:
	json_data=open(iconset + '/Contents.json')
	newdata = []

	data = json.load(json_data)
	for img in data["images"]:
		size = int(re.sub(r'x.+$','', img["size"]))
		filename='{idiom:s}_{size:d}_{scale}.png'.format(idiom=img["idiom"],scale=img["scale"],size=size)
		filepath='{iconset:s}/{filename:s}'.format(iconset=iconset,filename=filename)
		if img["scale"] == '2x':
			size = size * 2
		newdata.append({ "filename" : filename, "size" : img["size"], "idiom" : img["idiom"], "scale" :img["scale"] })
		print('{filename:s} {size:d}'.format(filename=filename,size=size))
		call(['sips', '-s', 'format', 'png', '-Z', str(size), '-o', filepath, 'icon.pdf'])
	json_data.close()
	contents_file = open(iconset + '/Contents.json', "w")
	contents_file.write( json.dumps({ "images" : newdata, "info" : { "version" : 1, "author" : "andy's python script" }}) )
	contents_file.close()

Here’s a gist:

I’ve read that you’re supposed to be able to use git rebase to move commits from an old repo to a one after using git filter-branch. But I couldn’t get that to work.

The backstory: Our repo was bloated because we started by forking a different project, and then deleted unneeded parts. This was an easy way to get started, but we ended up with all the history of the old project. So I ran git filter-branch and some other tools to clean up the history and remove empty merge commits. While I was preparing that, the rest of the team kept working on the old repo.

So I had to move those commits the rest of the team made onto the new, filtered repo. I used git format-patch and git am. Like this (assuming cwd is the new repo):


( cd ../old-repo; git format-patch --stdout -k commit id on old-repo of last shared commit ) | git am -k


Edit ~/.ssh/config


Host git git.mycompany.com

Hostname git.mycompany.com
IdentityFile ~/.ssh/github_rsa


A new phase in my life starts…

Leo (short for Leonard, in honor of Leonard Nimoy) on the left, and Chester on the right.

Me with Leo (Leo has the science-officer blue collar).

These best buds comforted each other on the scary ride from the farm outside of New Ulm where they grew up.

Both GDB and LLDB by default will stop when a debugged process receives a signal. Some libraries, such as the mongoose HTTP server, will generate SIGPIPE as a matter of course and that can be “normal”. However, the debuggers stop anyhow.

Google result currently shows this GDB command can be entered to stop the behavior:

handle SIGPIPE nostop


The LLDB equivalent is not obvious, but I found that this will do it:


process handle SIGPIPE -n true -p true -s false