DRAFT: Wifi connect example

Dockerfile.template

@@ -1,9 +1,42 @@
 # see more about dockerfile templates here: https://www.balena.io/docs/learn/develop/dockerfile/
 FROM python:3.13-slim-bookworm
 
-# Set our working directory
+RUN apt-get update && apt-get install -y --no-install-recommends \
+    curl \
+    dnsmasq \
+    wireless-tools
+
+# use latest version. If specific version is required, it should be provided as vX.Y.Z, e.g v4.11.37
+ARG VERSION="latest"
+
+# create /usr/src/app/ui directory where we will extract pre-built UI 
+WORKDIR /usr/src/app/ui
+
 WORKDIR /usr/src/app
 
+RUN \
+    export BASE_URL="https://github.com/balena-os/wifi-connect/releases" &&\    
+    DETECTED_ARCH=$(uname -m) &&\
+    case $DETECTED_ARCH in \
+        "aarch64") \
+            BINARY_ARCH_NAME="aarch64-unknown-linux-gnu" ;; \
+        "x86_64") \
+            BINARY_ARCH_NAME="x86_64-unknown-linux-gnu" ;;\
+        "armv7l") \
+            BINARY_ARCH_NAME="armv7-unknown-linux-gnueabihf" ;;\
+        *) \
+            echo >&2 "error: unsupported architecture ($DETECTED_ARCH)"; exit 1 ;; \ 
+    esac;\
+    if [ ${VERSION} = "latest" ]; then \
+        export URL_PARTIAL="latest/download" ; \
+    else \
+        export URL_PARTIAL="download/${VERSION}" ; \
+    fi; \
+    curl -Ls "$BASE_URL/$URL_PARTIAL/wifi-connect-$BINARY_ARCH_NAME.tar.gz" \
+    | tar -xvz -C  /usr/src/app/ && \
+    curl -Ls "$BASE_URL/$URL_PARTIAL/wifi-connect-ui.tar.gz" \
+    | tar -xvz -C  /usr/src/app/ui
+
 # Copy requirements.txt first for better cache on later pushes
 COPY requirements.txt requirements.txt
 
@@ -13,5 +46,9 @@ RUN pip install -r requirements.txt
 # This will copy all files in our root to the working  directory in the container
 COPY . ./
 
+COPY scripts/start.sh .
+
+ENV DBUS_SYSTEM_BUS_ADDRESS unix:path=/host/run/dbus/system_bus_socket
+
 # main.py will run when container starts up on the device
-CMD ["python","-u","src/app.py"]
+CMD ["sh", "./start.sh"]

docker-compose.yml

@@ -4,4 +4,8 @@ services:
   balena-hello-world:
     build: .
     ports:
-      - "80:80"
+      - "80:80"
+    volumes:
+      - /run/dbus:/host/run/dbus:ro
+    labels:
+      io.balena.features.dbus: "1"

requirements.txt

@@ -1,8 +1,8 @@
-click==8.1.8
-Flask==2.3.3
-importlib-metadata==4.13.0
-itsdangerous==2.2.0
-Jinja2==3.1.6
-MarkupSafe==2.1.5
-Werkzeug==2.0.3
-zipp==3.21.0
+click
+Flask
+importlib-metadata
+itsdangerous
+Jinja2
+MarkupSafe
+Werkzeug
+zipp

scripts/start.sh

@@ -0,0 +1,34 @@
+#!/usr/bin/env bash
+sleep 1  # give Supervisor time to attach log stream
+set -x
+
+export DBUS_SYSTEM_BUS_ADDRESS=unix:path=/host/run/dbus/system_bus_socket
+
+# Optional step - it takes couple of seconds (or longer) to establish a WiFi connection
+# sometimes. In this case, following checks will fail and wifi-connect
+# will be launched even if the device will be able to connect to a WiFi network.
+# If this is your case, you can wait for a while and then check for the connection.
+# sleep 15
+
+# Choose a condition for running WiFi Connect according to your use case:
+
+# 1. Is there a default gateway?
+# ip route | grep default
+
+# 2. Is there Internet connectivity?
+# nmcli -t g | grep full
+
+# 3. Is there Internet connectivity via a google ping?
+# wget --spider http://google.com 2>&1
+
+# 4. Is there an active WiFi connection?
+iwgetid -r
+
+if [ $? -eq 0 ]; then
+    printf 'Skipping WiFi Connect\n'
+else
+    printf 'Starting WiFi Connect\n'
+    ./wifi-connect
+fi
+
+python -u src/app.py

src/app.py

@@ -6,4 +6,5 @@ def hello_world():
     return render_template('index.html')
 
 if __name__ == '__main__':
+    print('Starting Hello World')
     app.run(host='0.0.0.0', port=80)