Mac developer? Clean up your app

The reason for this article should be obvious: too many OS X third party developers do an absolutely terrible job of building and packaging their applications. rixstep

Too many apps are shipped with debug symbols, uncompressed images, redundant files or generally useless rubbish that not only wastes users’ disk space, it ultimately ends up increasing the developer’s own bandwidth costs.

It’s not just the script kiddies at fault. Path Finder weighs in at over 60 MB on disk, but after a few simple operations, is halved in size to just over 30 MB. AppZapper can be trimmed from three megabytes to just one. Xslimmer (ironically) is over 80% junk, going from 5 MB on disk to a meagre 1 MB after being cleaned. In this case, the disk image is three times as big as the cleaned, uncompressed app. Starting to see the trend? Almost every app can be cleaned up to save a good deal of space.

Deploying your app

Rixstep provide instructions on deploying OS X apps covering most of the major areas.

Essentially, you need to:

Remove Junk: Get rid of all .DS_Store files. In Cocoa apps, remove PkgInfo. You should only have objects.nib or keyedobjects.nib in your nibs: remove classes.nib, info.nib, and data.dependency; these are not relevant for the user. Also remove all header files from your app and from embedded frameworks.
Clean up localization: Keep all non-language-specific resources in the Resources folder rather than duplicating them in each .lproj folder. Look through the framework you’re embedding, and remove any unnecessary files files. That includes language projects which your main app doesn’t support.
Compress images: Make sure all your images are compressed, especially if they’re in TIFF format. (But you shouldn’t use images for simple graphics like curves or gradients anyway; there are Cocoa drawing routines for that and NSBezierPath is your friend)
Trim binaries: Do not release an app that has been built using the Xcode “Debug” configuration. Remove the debug symbols from your build product, and if possible, release architecture-specific versions of your app, as well as a universal binary.

Get all the details in Building and Packaging Native OS X Applications.

Automation

A relevant question is: are there any tools that automate this process? And the answer has to be ‘not up to now there aren’t’. Until something comes along to save users from these issues it’s still all up to that developer you trust. Rixstep

There is finally a tool that automates at least some of the cleaning process. Say hello:

Go get trim-app

Trim-app is a shell script. It:

Cleans out all the horrible .DS_Store files
Removes unnecessary info.nib, classes.nib, and data.dependency files from inside nibs
Strips “fat” universal binaries to contain code for a chosen architecture only
Eliminates debug symbols that may be left in your application

You can perform all procedures at once, one at a time, multiple at a time, etc. using different parameters or flags (run trim-app -h for help).

The script searches the current working directory including every subdirectory so no files are missed. Even embedded frameworks are scanned through and cleaned out. So make sure you’re in the right directory before running (use the pwd command if unsure)

All changes performed are permanent and non-recoverable. (If you’re writing the app, that shouldn’t be a problem. Just build it again if something goes wrong)

While it’s written for cleaning out applications, this script is also great for general tasks - cleaning out .DS_Store files in a certain folder, for example.

Installation

Unzip the download.
Open Terminal and navigate to the folder where the unzipped trim-app is.
Run chmod 0700 trim-app. This makes sure only you can execute it.

If you want easy access to the command, move the file to /usr/bin/ by running sudo mv trim-app /usr/bin/. You’ll be asked for the admin password, then file will be moved.

You can now test if it’s working by running trim-app -h. Instructions for trim-app will appear. Once you’re done reading them, press q to exit, and start using it!

Usage

Running the shell script without any parameters will attempt to run all four procedures. You’ll be prompted for an architecture to keep in universal binaries. Leave this blank (just hit return) to leave universal binaries universal, or type in an architecture to keep (usually ppc or i386) if you want them stripped down.

Here’s an example of how you would use it in the Terminal:

% cd myApp.app/
% trim-app
Architecture to keep? (ppc/i386) ppc
   Removing .DS_Store files…
   Trimming nibs…
   Trimming universal binaries…
   Stripping debug symbols…
   Cleaning up…
Done.
%

If you don’t want to be prompted each time for the architecture, use either --all (as in, trim-app --all) (which will run everything except the liposuction of universal binaries), or add the architecture to keep immediately after, like trim-app --all ppc.

Add a -p flag to the end if you want to see a list of affected files. For example,

% trim-app --all i386 -p

You can also run individual procedures. The following cleans out .DS_Stores from the entire Macintosh HD:

% cd /
% sudo trim-app -d

Run trim-app -h to find out more about the available parameters.

Don’t forget the standard shell practices still apply. Ctrl-C any time during operation to immediately halt execution, save output to a file with trim-app -p > trim-log.txt, and so on.

Lastly, remember that while this shell script does a lot of the work (and there is an application called CleanApp which can help remove unnecessary lproj files), it’s still up to you to take care of removing headers, compressing images, etc.

Mac developer? Clean up your app

Deploying your app

Automation

Installation

Usage

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