build.md

NB! This project requires LoopWorkspace dev. You must use the workspace to buid this.

Start with a clean LoopWorkspace based on dev

• Download a fresh copy of LoopWorkspace dev into a subfolder of your choice

cd ~
mkdir Code && cd Code
git clone --branch=dev --recurse-submodules https://github.com/LoopKit/LoopWorkspace
cd LoopWorkspace

• Add LibreTransmitter submodule

git submodule add -b main git@github.com:dabear/LibreTransmitter.git LibreTransmitter

• Add Glucose algorithm (GetGlucoseFromRaw.swift)
  • First Download GetGlucoseFromRaw.swift from this external repo and put it in the Download folder on your mac: https://raw.githubusercontent.com/gui-dos/DiaBLE/main/Reversing/GlucoseFromRaw.swift
  • Add GetGlucoseFromRaw.swift into project. For example:

cd ~/Downloads
mv GlucoseFromRaw.swift ~/Code/LoopWorkspace/LibreTransmitter/LibreSensor/GlucoseAlgorithm/GlucoseFromRaw.swift

In Xcode, Add LibreTransmitter project into LoopWorkspace

• Open LoopWorkspace.xcworkspace

• Drag LibreTransmitter.xcodeproj from the Finder (from the LibreTransmitter submodule) into the xcode left menu while having the loop workspace open

• It should Look like this:

• Make sure the default "LoopWorkspace" scheme is selected and then "Edit scheme.."

• In the Build Dialog, make sure to add LibreTransmitterPlugin as a build target, and place it just before "ShareClientPlugin"

• In Xcode 13 this can be accessed from the top menu Product -> Scheme -> Edit Scheme

• it should look like this:

Give Loop Extra background permissions

The LibreTransmitter plugin will run as a part of Loop. If you want LibreTransmitter to be able to give vibrations for low/high glucose, this is a necessary step

• In Xcode, Open the Loop Project (not the LibreTransmitter project) in the navigator, go to "Signing & Capabilities", then under "background modes", select "Audio, AirPlay, and Picture in picture". This will allow Libretransmitter to use vibration when the phone is locked.
• It should look like this:

Give Loop NFC permissions for libre2 direct bluetooth support

This plugin now supports libre2 direct bluetooth connections. To utilize libre2direct you need to pair your sensor via NFC first, and therefore Loop needs NFC permissions

• In Xcode, Open the Loop Project (not the LibreTransmitter project) in the navigator, go to "Signing & Capabilities", then "+ Capability" and add the "NFC" or "Near field communication Tag Reading" capability.
• In Loop's Info.plist, add the tag NFCReaderUsageDescription and set description to something similar to: "Loop will use NFC on the phone to pair libre2 sensors"

Give Libretransmitter Critical Alerts permissions

Libretransmitter will by default send alarms as "timesensitve", appearing immediately on the lock screen. If you mute or set your phone to do not disturb, you can potentially miss out on such alarms. To remedy this, LibreTransmitter can be configured to try to upgrade any glucose alarms to "critical". Critical alarms will sound even if your phone is set to to mute or "do not disturb" mode.

For this to be possible, you will have to request special permissions from apple. This process is documented at https://stackoverflow.com/questions/66057840/ios-how-do-you-implement-critical-alerts-for-your-app-when-you-dont-have-an-en . The linked article describes some necessary code changes, but the code changes mentioned there should be ignored.

It's worth mentioning again that those permissions must be given to Loop itself, not to the LibreTransmitter package. The com.apple.developer.usernotifications.critical-alerts permission must be added to Loop/Loop.entitlement file in the Loop folder (not inside LibreTransmitter

Method 1

Using this method, only the LibreTransmitter cgm alarms can become critical

You should only change the shouldOverrideRequestCriticalPermissions toggle in the NotificationHelperOverride.swift file to true, like this:

enum NotificationHelperOverride {
    static var shouldOverrideRequestCriticalPermissions : Bool {
        // if you want LibreTransmitter to try upgrading to critical notifications, change this
        true
    }
}

Method 2

Using this method, both Loop pump, cgm alarms and LibreTransmitter alarms will become critical

Go to the Loop Project (not target)→Build settings → Swift Compiler → Custom flags → Other swift flags section and edit the different configuration flags. Add the flag “CRITICAL_ALERTS_ENABLED” (without the quotes).

Build the LoopWorkspace with LibreTransmitter Plugin

• In xcode, go to Product->"Clean Build Folder"
• Make sure you build "Loop (Workspace)" rather than "Loop"