README-dev.md

Developer Notes

This document is to remind me of things that are useful during development, but which I will probably forget!

Creating the gem

I used bundler to create boiler plate for a gem with an executable:

$ bundle gem --exe iphoneutils

Experimenting

To fire up irb with the library loaded:

$ bin/console`

Documents consulted

During the development, I looked at these:

• Restore or copy iPhone contacts to another phone using Linux - how to use idevicebackup2 and ideviceunback to get the data from the iPhone.
• ifuse for mounting the iPhone locally using fuse:

$ mkdir -p ~/media/iphone
$ ifuse ~/media/iphone

• How to write your first CLI with Thor
• What is Thor?
• How to create a Ruby gem with Bundler

Files on the iPhone

Recordings

This directory contains audio recorded by the Voice Memos app. The recordings are stored on the iPhone in a Recordings directory with file names containing timestamps. e.g. 20190716 203652.m4a.

There's a file called AssetManifest.plist that maps the names of the .m4a files onto the titles that you see in the user interface of the Voice Memos app. It is an Apple plist in XML format. Here's an example that maps a .m4a file name onto the name 'God Only Knows':

    <key>20140701 205735.m4a</key>
        <dict>
                <key>hasChanges</key>
                <false/>
                <key>name</key>
                <string>God Only Knows</string>
                <key>pid</key>
                <integer>7608165057324974017</integer>
        </dict>

Fortunately, there's a ruby gem plist to convert it into a Hash.

If only things were that simple! Sometimes, the .m4a file mentioned in the <key> does not exist. In this case, there is another place where .m4a files may lurk. An example:

$ ls Recordings/20180802\ 222805.composition/fragments/*.m4a
'Recordings/20180802 222805.composition/fragments/7F1452E7-3DD9-4287-A875-7C440D545B2B.m4a'

Running the exe

Without installing the gem, commands can be run like this:

$ bundle exec exe/iphoneutils copy recordings ~/media/iphone/Recordings/ my-target-dir

Installing the gem

I generally install gems with --user-install to put them in my local tree. This seemed to do the job for version 0.1.0:

$ bundle exec rake install
$ gem install --user-install pkg/iphoneutils-0.1.0.gem