Add automatic connection option

Author: maggie44

README.md

@@ -1,5 +1,4 @@
 ## Description
-
 An API for controlling Wi-Fi connections on [Balena](https://www.balena.io/os/) devices.
 
 It does not contain an interface, instead it provides API endpoints to send requests to interact with the device. Any interface of your choice can be built to interact with the API. If you develop an interface that is open source, please do let me know so I can provide people links. 
@@ -13,21 +12,28 @@ You can set your own default Wi-Fi SSID and a Wi-Fi password for your hotspot us
 
 Enjoy and please do feel free to feedback experiences and issues.
 
-## Securing the API
+## Automatic connections
+You can specify a Wi-Fi connection you would like your device to try and connect to the first time it loads by using the environment variables in the docker-compose.yml file. Once this connection is established, the device will stay connected after reboots until you use the `forget` endpoint. If the network is not available, the hotspot will start instead.
 
+````
+PWC_SSID: "network-name" # The SSID of the network you would like to try and auto-connect.
+USERNAME: "username" # Optional, for enterprise networks
+PWC_PASSWORD: "your-password" # Optional, the password associated with the Wi-Fi network. Must be 8 characters or more. 
+````
+
+## Securing the API
 By default, the API is exposed so your interface can interact directly. In other words, anyone can go to `http://your-device:9090/v1/connect` to send commands to your device. 
 
-If you would prefer to only allow access from your backend, change the `host` environment variable to `127.0.0.1`. Then ensure your backend container is connected to the host network so it matches the API docker-compose.yml file in this repo:
+If you would prefer to only allow access from your backend, change the `PWC_HOST` environment variable to `127.0.0.1`. Then ensure your backend container is connected to the host network so it matches the API docker-compose.yml file in this repo:
 
 `network_mode: "host"`
 
 Users will then be unable to access the API `http://your-device:9090/v1/connect`. Your backend container on the device, however, can reach the API using `http://127.0.0.1:9090/v1/connect`. This is useful if your interface has a login process, and you only want users to be able to interact with Wi-Fi after logging in.
 
-Alternatively, if you would rather have your backend use specified ports instead of the host network, you can change the `host` environment variable to `172.17.0.1` and access the API from `http://172.17.0.1:9090/v1/connect`.
+Alternatively, if you would rather have your backend use specified ports instead of the host network, you can change the `PWC_HOST` environment variable to `172.17.0.1` and access the API from `http://172.17.0.1:9090/v1/connect`.
 
 
 ## Endpoints
-
 ### http://your-device:9090/v1/connect
 Connect to a nearby Wi-Fi access point.
 

docker-compose.yml

@@ -3,10 +3,20 @@ version: '2.1'
 services:
   py-wifi-connect:
     environment:
-      HOTSPOT_SSID: "Py Wi-Fi Connect"
-      #HOTSPOT_PASSWORD: "my-hotspot-password" # Hotspot passwords must be 8 characters or more.
-      HOST: "0.0.0.0"
-      PORT: 9090
+      ## Listening IP and port ##
+      PWC_HOST: "0.0.0.0"
+      PWC_PORT: 9090
+
+      ## Hotspot details ##
+      PWC_HOTSPOT_SSID: "Py Wi-Fi Connect"
+      #HOTSPOT_PASSWORD: "my-hotspot-password" # Optional hotspot password. Must be 8 characters or more.
+
+      ## Try to automatically set up a Wi-Fi network on first boot ##
+      #PWC_SSID: "network-name" # Compulsory for this feature
+      #USERNAME: "username" # Optional
+      #PWC_PASSWORD: "your-password" # Optional. Must be 8 characters or more. 
+
+      ## System Variables ##
       DBUS_SYSTEM_BUS_ADDRESS: "unix:path=/host/run/dbus/system_bus_socket"
     build:
       context: .

src/common/wifi.py

@@ -47,6 +47,24 @@ def analyse_access_point(ap):
     return entry
 
 
+def auto_connect(ssid=None,
+                 username=None,
+                 password=None):
+    ssids, _ = list_access_points()
+
+    for ssid_item in ssids:
+        if ssid_item['ssid'] == ssid:
+            connect(conn_type=ssid_item['conn_type'],
+                    ssid=ssid,
+                    username=username,
+                    password=password)
+            break
+    else:
+        logger.info('Auto-connect failed as the device could not find the '
+                    'specified network.')
+        connect()
+
+
 def check_internet_status(host="8.8.8.8", port=53, timeout=5):
     try:
         socket.setdefaulttimeout(timeout)
@@ -236,7 +254,7 @@ def refresh_networks(retries=5):
             logger.error('Unknown error calling IW.')
             return False
         else:
-            logger.info('IW succeeded.')
+            logger.debug('IW succeeded.')
             return True
         finally:
             run += 1

src/config.py

@@ -1,29 +1,41 @@
 import os
 
 # Set default Wi-Fi SSID.
-if "HOTSPOT_SSID" in os.environ:
-    hotspot_ssid = os.environ['HOTSPOT_SSID']
+if "PWC_HOTSPOT_SSID" in os.environ:
+    hotspot_ssid = os.environ['PWC_HOTSPOT_SSID']
 else:
     hotspot_ssid = "Py Wi-Fi Connect"
 
 # Set default hotspot password.
-if "HOTSPOT_PASSWORD" in os.environ:
-    hotspot_password = os.environ['HOTSPOT_PASSWORD']
+if "PWC_HOTSPOT_PASSWORD" in os.environ:
+    hotspot_password = os.environ['PWC_HOTSPOT_PASSWORD']
 else:
     hotspot_password = None
 
 # Set default host.
-if "HOST" in os.environ:
-    host = os.environ['HOST']
+if "PWC_HOST" in os.environ:
+    host = os.environ['PWC_HOST']
 else:
     host = '0.0.0.0'
 
 # Set default port.
-if "PORT" in os.environ:
-    port = os.environ['PORT']
+if "PWC_PORT" in os.environ:
+    port = os.environ['PWC_PORT']
 else:
     port = 9090
 
+# Compile kwargs for automatic connection
+if "PWC_SSID" in os.environ:
+    auto_connect_kargs = \
+        {"ssid": os.environ['PWC_SSID']}
+
+    if "PWC_USERNAME" in os.environ:
+        auto_connect_kargs.update(username=os.environ['PWC_USERNAME'])
+    if "PWC_PASSWORD" in os.environ:
+        auto_connect_kargs.update(password=os.environ['PWC_PASSWORD'])
+else:
+    auto_connect_kargs = False
+
 # Default access point name. No need to change these under usual operation as
 # they are for use inside the app only. PWC is acronym for 'Py Wi-Fi Connect'.
 ap_name = 'PWC'

src/run.py

@@ -1,10 +1,12 @@
 import atexit
+import config
 import signal
 import sys
 import time
 from common.errors import errors
 from common.errors import logger
 from common.system import dnsmasq
+from common.wifi import auto_connect
 from common.wifi import check_wifi_status
 from common.wifi import connect
 from common.wifi import refresh_networks
@@ -29,6 +31,7 @@ def handle_sigterm(*args):
 
 # Startup process
 if __name__ == '__main__':
+    logger.info('Starting...')
     # Load Flask-Restful API
     api = Api(errors=errors)
 
@@ -51,9 +54,13 @@ def handle_sigterm(*args):
     if check_wifi_status():
         logger.info('Wi-Fi connection already established.')
     else:
-        logger.info('Starting hotspot...')
         refresh_networks(retries=1)
-        connect()
+        if config.auto_connect_kargs:
+            logger.info('Attempting auto-connect...')
+            auto_connect(**config.auto_connect_kargs)
+        else:
+            logger.info('Starting hotspot...')
+            connect()
 
     # Configure endpoints #