Add device tracker for Linksys Smart Wifi devices (#8144)

* Add device tracker for Linksys Smart Wifi devices

* Fixing code style

.coveragerc

@@ -245,6 +245,7 @@ omit =
     homeassistant/components/device_tracker/gpslogger.py
     homeassistant/components/device_tracker/icloud.py
     homeassistant/components/device_tracker/linksys_ap.py
+    homeassistant/components/device_tracker/linksys_smart.py
     homeassistant/components/device_tracker/luci.py
     homeassistant/components/device_tracker/mikrotik.py
     homeassistant/components/device_tracker/netgear.py

homeassistant/components/device_tracker/linksys_smart.py

@@ -0,0 +1,110 @@
+"""Support for Linksys Smart Wifi routers."""
+import logging
+import threading
+from datetime import timedelta
+
+import requests
+import voluptuous as vol
+
+import homeassistant.helpers.config_validation as cv
+from homeassistant.components.device_tracker import (
+    DOMAIN, PLATFORM_SCHEMA, DeviceScanner)
+from homeassistant.const import CONF_HOST
+from homeassistant.util import Throttle
+
+MIN_TIME_BETWEEN_SCANS = timedelta(seconds=5)
+DEFAULT_TIMEOUT = 10
+
+_LOGGER = logging.getLogger(__name__)
+
+PLATFORM_SCHEMA = PLATFORM_SCHEMA.extend({
+    vol.Required(CONF_HOST): cv.string,
+})
+
+
+def get_scanner(hass, config):
+    """Validate the configuration and return a Linksys AP scanner."""
+    try:
+        return LinksysSmartWifiDeviceScanner(config[DOMAIN])
+    except ConnectionError:
+        return None
+
+
+class LinksysSmartWifiDeviceScanner(DeviceScanner):
+    """This class queries a Linksys Access Point."""
+
+    def __init__(self, config):
+        """Initialize the scanner."""
+        self.host = config[CONF_HOST]
+
+        self.lock = threading.Lock()
+        self.last_results = {}
+
+        # Check if the access point is accessible
+        response = self._make_request()
+        if not response.status_code == 200:
+            raise ConnectionError("Cannot connect to Linksys Access Point")
+
+    def scan_devices(self):
+        """Scan for new devices and return a list with device IDs (MACs)."""
+        self._update_info()
+
+        return self.last_results.keys()
+
+    def get_device_name(self, mac):
+        """Return the name (if known) of the device."""
+        return self.last_results.get(mac)
+
+    @Throttle(MIN_TIME_BETWEEN_SCANS)
+    def _update_info(self):
+        """Check for connected devices."""
+        with self.lock:
+            _LOGGER.info("Checking Linksys Smart Wifi")
+
+            self.last_results = {}
+            response = self._make_request()
+            if response.status_code != 200:
+                _LOGGER.error(
+                    "Got HTTP status code %d when getting device list",
+                    response.status_code)
+                return False
+            try:
+                data = response.json()
+                result = data["responses"][0]
+                devices = result["output"]["devices"]
+                for device in devices:
+                    macs = device["knownMACAddresses"]
+                    if not macs:
+                        _LOGGER.warning(
+                            "Skipping device without known MAC address")
+                        continue
+                    mac = macs[-1]
+                    connections = device["connections"]
+                    if not connections:
+                        _LOGGER.debug("Device %s is not connected", mac)
+                        continue
+                    name = device["friendlyName"]
+                    properties = device["properties"]
+                    for prop in properties:
+                        if prop["name"] == "userDeviceName":
+                            name = prop["value"]
+                    _LOGGER.debug("Device %s is connected", mac)
+                    self.last_results[mac] = name
+            except (KeyError, IndexError):
+                _LOGGER.exception("Router returned unexpected response")
+                return False
+            return True
+
+    def _make_request(self):
+        # Weirdly enough, this doesn't seem to require authentication
+        data = [{
+            "request": {
+                "sinceRevision": 0
+            },
+            "action": "http://linksys.com/jnap/devicelist/GetDevices"
+        }]
+        headers = {"X-JNAP-Action": "http://linksys.com/jnap/core/Transaction"}
+        return requests.post('http://{}/JNAP/'.format(self.host),
+                             timeout=DEFAULT_TIMEOUT,
+                             headers=headers,
+                             json=data)