The goal of Rigablue is to provide an easy to use library for Bluetooth Low Energy (BLE) device integration. Rigablue provides classes which abstract away many of the low level details required for typical BLE operations: scanning, connecting, and communications.
The main tenant of the current Rigablue architecture is the Observer pattern. This pattern meets the needs of a sychronous data flow but also provides for asynchronous data recpetion as needed. While not the best choice of designs for modern iOS and Android development, it is the overarching pattern for the current architecture.
Another common design tenant are the manager classes. The classes follow a singleton design. The manager classes provide the ability to scan for BLE devices and connect with them. These operations are provided by the Discovery manager and Connection manager respectively. As with use of the observer pattern, this may not be the best choice for modern application design.
To begin scanning for a BLE device, a request object is first created. The request object holds scanning parameters such as Service UUIDs to search for, amount of time to run the scan, and other OS specific parameters.
After kicking off a discovery request, the request parameters will be supplied to the low level bluetooth stack. The discovery request can result in a few different callbacks: didDiscoverDevice, discoveryDidTimeout, bluetoothPowerStateChanged, bluetoothNotSupported.
As each discovery report is returned, the device information is coalesced into an available device object. This object contains fields such as device name, address or UUID (on iOS), advertising data, RSSI, and a timestamp of discovery. This object is then used to initiate connections via the connection manager.
To connect with a BLE device, an available device object is provided to the connection manager. The connection manager then reports the connection success via one of the observer callbacks. The connection manager is dualy responsible for handling disconnections and provides a separate callback after a disconnection is complete as reported by the low level Bluetooth stack.
After connection, the RigLeBaseDevice object is provided for all interaction purposes. This object can be queired for the various characteristics available on a device and also encapsulates items such as the advertisement data found during discovery. This object needs further expansions to include more basic services such as auto-population of the Device Information Service and, at least for iOS, easier access functions.