Added more examples for rpc's usage (#4)

* add usage example for attribute requests

* add usage example for attribute update

* remove extra client initialization from rpc example

* fix ruff formatting

* fix formatting

* fix formatting

* select better variable name for MQTT loop timeout

Author: Andry925

examples/attribute_requests.py

@@ -0,0 +1,42 @@
+# SPDX-FileCopyrightText: 2017 Scott Shawcroft, written for Adafruit Industries
+# SPDX-FileCopyrightText: Copyright (c) 2026 ThingsBoard Inc.
+#
+# SPDX-License-Identifier: Unlicense
+
+import time
+
+import wifi  # CircuitPython Wi-Fi module
+
+from tb_device_mqtt import TBDeviceMqttClient  # ThingsBoard MQTT client wrapper (your SDK)
+
+# Sanity check: Wi-Fi must be connected before MQTT
+print("WiFi connected:", wifi.radio.connected)
+print("IP:", wifi.radio.ipv4_address)
+
+# ThingsBoard connection settings
+HOST = "YOUR_HOST"  # e.g. "thingsboard.cloud" or "192.168.1.10"
+PORT = 1883  # standard MQTT port (non-TLS)
+TOKEN = "YOUR_ACCESS_TOKEN"  # device access token from ThingsBoard
+TIMEOUT = 20  # how long we keep pumping MQTT loop (seconds)
+
+# Create and connect MQTT client
+client = TBDeviceMqttClient(host=HOST, port=PORT, access_token=TOKEN)
+client.connect()  # establishes MQTT session + subscriptions inside your SDK (if implemented)
+
+
+def on_attributes_change(result, exception=None):
+    # Callback is called when the attributes response arrives
+    if exception is not None:
+        print("Exception:", exception)
+    else:
+        print("Attributes response:", result)
+
+
+# Request client/shared attributes by keys (your SDK forms attributes/request/<id>)
+client.request_attributes(client_keys=["atr1", "atr2"], callback=on_attributes_change)
+
+# IMPORTANT: CircuitPython needs a loop to receive/process MQTT packets
+deadline = time.monotonic() + TIMEOUT
+while time.monotonic() < deadline:
+    client.check_for_msg()  # wraps MiniMQTT.loop() -> triggers callbacks
+    time.sleep(0.05)  # small sleep to reduce CPU usage

examples/attribute_update.py

@@ -0,0 +1,40 @@
+# SPDX-FileCopyrightText: 2017 Scott Shawcroft, written for Adafruit Industries
+# SPDX-FileCopyrightText: Copyright (c) 2026 ThingsBoard Inc.
+#
+# SPDX-License-Identifier: Unlicense
+
+import time
+
+import wifi  # CircuitPython Wi-Fi module
+
+from tb_device_mqtt import TBDeviceMqttClient  # ThingsBoard MQTT client wrapper (your SDK)
+
+# Sanity check: Wi-Fi must be connected before MQTT
+print("Connected:", wifi.radio.connected)
+print("IP:", wifi.radio.ipv4_address)
+
+# ThingsBoard connection settings
+HOST = "YOUR_HOST"  # e.g. "thingsboard.cloud" or "192.168.1.10"
+PORT = 1883  # standard MQTT port (non-TLS)
+TOKEN = "YOUR_ACCESS_TOKEN"  # device access token from ThingsBoard
+TIMEOUT = 20  # how long we keep pumping MQTT loop (seconds)
+
+# Create and connect MQTT client
+client = TBDeviceMqttClient(host=HOST, port=PORT, access_token=TOKEN)
+client.connect()
+
+
+def callback(result, *args):  # noqa: F841
+    # Called when subscribed attribute update arrives
+    # (extra args may contain metadata depending on your SDK design)
+    print("Received data:", result)
+
+
+# Subscribe to updates of a single attribute key (e.g. shared attribute "frequency")
+sub_id = client.subscribe_to_attribute("frequency", callback)  # returns subscription id (optional)
+
+# IMPORTANT: keep looping so incoming MQTT messages are processed
+deadline = time.monotonic() + TIMEOUT
+while time.monotonic() < deadline:
+    client.check_for_msg()  # wraps MiniMQTT.loop() -> triggers callbacks
+    time.sleep(0.05)  # small sleep to reduce CPU usage

examples/rpc_example.py

@@ -21,10 +21,6 @@
 RPC_METHODS = ("Pwd", "Ls")
 
 
-# Create MQTT client instance
-client = TBDeviceMqttClient(host=HOST, port=PORT, access_token=TOKEN)
-
-
 def on_server_side_rpc_request(request_id, request_body):
     # request_id: numeric id from the MQTT topic
     # request_body: decoded JSON dict, typically {"method": "...", "params": ...}
@@ -65,6 +61,7 @@ def on_server_side_rpc_request(request_id, request_body):
             client.send_rpc_reply(request_id, reply)
 
 
+# Create MQTT client instance
 client = TBDeviceMqttClient(HOST, port=PORT, access_token=TOKEN)
 # Register the server-side RPC callback before the main loop
 client.set_server_side_rpc_request_handler(on_server_side_rpc_request)