Ble scanner doc (#611)

* Added ble_scanner documentation.

* Added ble_scanner link into /index.rst

* Update components/text_sensor/ble_scanner.rst

Improved sensor description.

Co-Authored-By: Otto Winter <otto@otto-winter.com>

* ble_scanner: esphome.io link replaced with ref.

* ble_scanner-doc: fixed bar length

Co-authored-by: Otto Winter <otto@otto-winter.com>

components/esp32_ble_tracker.rst

@@ -52,6 +52,7 @@ for information on how you can find out the MAC address of a device and track it
     resized. Please flash the ESP32 via USB when adding this to your configuration. After that,
     you can use OTA updates again.
 
+.. _config-esp32_ble_tracker:
 
 Configuration variables:
 ------------------------

components/text_sensor/ble_scanner.rst

@@ -0,0 +1,48 @@
+ESP32 Bluetooth Low Energy Scanner
+==================================
+
+.. seo::
+    :description: Instructions for setting up BLE text sensors for the ESP32.
+    :image: bluetooth.png
+    :keywords: ESP32
+
+The ``ble_scanner`` text sensor platform lets you track reachable BLE devices.
+See the :ref:`BLE Tracker Configuration variables <config-esp32_ble_tracker>` for
+instructions for setting up scan parameters.
+The sensor platform is similar to :doc:`/components/sensor/ble_rssi` but in contrast to that platform, this text sensor sends out all raw BLE scan information and does not filter devices.
+
+The data this sensor publishes is intended to be processed by the remote (for example an MQTT client) and sends the data in JSON format.
+
+.. code-block:: yaml
+
+    # Example configuration entry
+    esp32_ble_tracker:
+
+    text_sensor:
+      - platform: ble_scanner
+        name: "BLE Devices Scanner"
+
+Example json log:
+
+.. code-block:: json
+
+    {
+        "timestamp":1578254525,
+        "address":"D7:E7:E7:66:DD:33",
+        "rssi":"-80",
+        "name":"MI Band 2"
+    }
+
+Configuration variables:
+------------------------
+
+-  **name** (**Required**, string): The name of the sensor.
+- All other options from :ref:`Text Sensor <config-text_sensor>`.
+
+See Also
+--------
+
+- :doc:`/components/esp32_ble_tracker`
+- :doc:`/components/text_sensor/index`
+- :apiref:`ble_scanner/ble_scanner.h`
+- :ghedit:`Edit`

index.rst

@@ -291,6 +291,7 @@ Text Sensor Components
     MQTT Subscribe Text, components/text_sensor/mqtt_subscribe, mqtt.png
     Version, components/text_sensor/version, new-box.svg
     WiFi Info, components/text_sensor/wifi_info, network-wifi.svg
+    BLE Scanner, components/text_sensor/ble_scanner, bluetooth.svg
     Template Text Sensor, components/text_sensor/template, description.svg
     Custom Text Sensor, components/text_sensor/custom, language-cpp.svg
     Custom UART Text Sensor, components/text_sensor/uart, language-cpp.svg