Rework the API to use descriptors.

.gitignore

@@ -4,3 +4,4 @@ _build
 .env
 build*
 bundles
+.DS_Store

.travis.yml

@@ -17,10 +17,10 @@ deploy:
 install:
 - pip install -r requirements.txt
 - pip install circuitpython-build-tools Sphinx sphinx-rtd-theme
-- pip install --force-reinstall pylint==1.9.2
+- pip install --force-reinstall "pylint<3"
 
 script:
-- pylint adafruit_ble/*.py
+- pylint --disable=too-few-public-methods adafruit_ble/**/*.py adafruit_ble/*.py
 - ([[ ! -d "examples" ]] || pylint --disable=missing-docstring,invalid-name,bad-whitespace
   examples/*.py)
 - circuitpython-build-bundles --filename_prefix adafruit-circuitpython-ble

README.rst

@@ -31,16 +31,18 @@ Usage Example
 
 .. code-block:: python
 
-    from adafruit_ble.uart import UARTServer
-
-    uart_server = UARTServer()
-    uart_server.start_advertising()
-
-    # Wait for a connection.
-    while not uart_server.connected:
-        pass
-
-    uart_server.write('abc')
+    from adafruit_ble import SmartAdapter
+
+    adapter = SmartAdapter()
+    print("scanning")
+    found = set()
+    for entry in adapter.start_scan(timeout=60, minimum_rssi=-80):
+        addr = entry.address
+        if addr not in found:
+            print(entry)
+        found.add(addr)
+
+    print("scan done")
 
 
 Contributing

adafruit_ble/__init__.py

@@ -1,6 +1,7 @@
 # The MIT License (MIT)
 #
 # Copyright (c) 2019 Dan Halbert for Adafruit Industries
+# Copyright (c) 2019 Scott Shawcroft for Adafruit Industries
 #
 # Permission is hereby granted, free of charge, to any person obtaining a copy
 # of this software and associated documentation files (the "Software"), to deal
@@ -26,7 +27,7 @@
 This module provides higher-level BLE (Bluetooth Low Energy) functionality,
 building on the native `_bleio` module.
 
-* Author(s): Dan Halbert for Adafruit Industries
+* Author(s): Dan Halbert and Scott Shawcroft for Adafruit Industries
 
 Implementation Notes
 --------------------
@@ -42,7 +43,148 @@
 
 """
 
-# imports
+import board
+import _bleio
+
+from .services import Service
+from .advertising import Advertisement
 
 __version__ = "0.0.0-auto.0"
 __repo__ = "https://github.com/adafruit/Adafruit_CircuitPython_BLE.git"
+
+class BLEConnection:
+    """This represents a connection to a peer BLE device.
+
+       It acts as a map from a Service type to a Service instance for the connection.
+    """
+    def __init__(self, connection):
+        self._connection = connection
+        self._discovered_services = {}
+        """These are the bare remote services from _bleio."""
+
+        self._constructed_services = {}
+        """These are the Service instances from the library that wrap the remote services."""
+
+    def _discover_remote(self, uuid):
+        remote_service = None
+        if uuid in self._discovered_services:
+            remote_service = self._discovered_services[uuid]
+        else:
+            results = self._connection.discover_remote_services((uuid.bleio_uuid,))
+            if results:
+                remote_service = results[0]
+                self._discovered_services[uuid] = remote_service
+        return remote_service
+
+    def __contains__(self, key):
+        uuid = key
+        if hasattr(key, "uuid"):
+            uuid = key.uuid
+        return self._discover_remote(uuid) is not None
+
+    def __getitem__(self, key):
+        uuid = key
+        maybe_service = False
+        if hasattr(key, "uuid"):
+            uuid = key.uuid
+            maybe_service = True
+
+        remote_service = self._discover_remote(uuid)
+
+        if uuid in self._constructed_services:
+            return self._constructed_services[uuid]
+        if remote_service:
+            constructed_service = None
+            if maybe_service:
+                constructed_service = key(service=remote_service)
+                self._constructed_services[uuid] = constructed_service
+            return constructed_service
+
+        raise KeyError("{!r} object has no service {}".format(self, key))
+
+    @property
+    def connected(self):
+        """True if the connection to the peer is still active."""
+        return self._connection.connected
+
+    def disconnect(self):
+        """Disconnect from peer."""
+        self._connection.disconnect()
+
+class BLERadio:
+    """The BLERadio class enhances the normal `_bleio.Adapter`.
+
+       It uses the library's `Advertisement` classes and the `BLEConnection` class."""
+
+    def __init__(self, adapter=None):
+        if not adapter:
+            adapter = _bleio.adapter
+        self._adapter = adapter
+        self._current_advertisement = None
+        self._connection_cache = {}
+
+    def start_advertising(self, advertisement, scan_response=None, **kwargs):
+        """Starts advertising the given advertisement.
+
+            It takes most kwargs of `_bleio.Adapter.start_advertising`."""
+        scan_response_data = None
+        if scan_response:
+            scan_response_data = bytes(scan_response)
+        self._adapter.start_advertising(bytes(advertisement),
+                                        scan_response=scan_response_data,
+                                        connectable=advertisement.connectable,
+                                        **kwargs)
+
+    def stop_advertising(self):
+        """Stops advertising."""
+        self._adapter.stop_advertising()
+
+    def start_scan(self, *advertisement_types, **kwargs):
+        """Starts scanning. Returns an iterator of advertisement objects of the types given in
+           advertisement_types. The iterator will block until an advertisement is heard or the scan
+           times out.
+
+           If any ``advertisement_types`` are given, only Advertisements of those types are produced
+           by the returned iterator. If none are given then `Advertisement` objects will be
+           returned."""
+        prefixes = b""
+        if advertisement_types:
+            prefixes = b"".join(adv.prefix for adv in advertisement_types)
+        for entry in self._adapter.start_scan(prefixes=prefixes, **kwargs):
+            adv_type = Advertisement
+            for possible_type in advertisement_types:
+                if possible_type.matches(entry) and issubclass(possible_type, adv_type):
+                    adv_type = possible_type
+            advertisement = adv_type.from_entry(entry)
+            if advertisement:
+                yield advertisement
+
+    def stop_scan(self):
+        """Stops any active scan.
+
+           The scan results iterator will return any buffered results and then raise StopIteration
+           once empty."""
+        self._adapter.stop_scan()
+
+    def connect(self, advertisement, *, timeout=4):
+        """Initiates a `BLEConnection` to the peer that advertised the given advertisement."""
+        connection = self._adapter.connect(advertisement.address, timeout=timeout)
+        self._connection_cache[connection] = BLEConnection(connection)
+        return self._connection_cache[connection]
+
+    @property
+    def connected(self):
+        """True if any peers are connected to the adapter."""
+        return self._adapter.connected
+
+    @property
+    def connections(self):
+        """A tuple of active `BLEConnection` objects."""
+        connections = self._adapter.connections
+        wrapped_connections = [None] * len(connections)
+        for i, connection in enumerate(self._adapter.connections):
+            if connection not in self._connection_cache:
+                self._connection_cache[connection] = BLEConnection(connection)
+            wrapped_connections[i] = self._connection_cache[connection]
+
+        return tuple(wrapped_connections)