The Python Flask code snippet you provided sets up a simple web server capable of receiving POST requests containing JSON data, specifically for temperature and humidity values. Here's a detailed breakdown of its components and functionality:
- Application Setup: The application is built using Flask, a lightweight WSGI web application framework in Python. It is designed to be quick and easy to get started with, making it an excellent choice for simple web APIs.
-
Endpoint:
'/data'
- This endpoint listens for POST requests. It is intended to receive JSON data that includes temperature and humidity readings.
-
Function:
sensor_data()
- This function processes incoming POST requests to the
/data
endpoint.
- This function processes incoming POST requests to the
-
JSON Data Retrieval:
data = request.get_json()
extracts JSON data from the incoming POST request. Flask automatically handles the parsing of JSON data if theContent-Type
header of the request is set toapplication/json
.
-
Data Processing:
- The temperature and humidity values are extracted from the JSON data using
data.get('temperature')
anddata.get('humidity')
. The.get()
method is used for safe access, which returnsNone
if the specified key does not exist, rather than throwing an error. - These values are then printed to the console with the format:
"Received temperature: {t}°C, humidity: {h}%"
. This logging is helpful for debugging and monitoring the data received by the server.
- The temperature and humidity values are extracted from the JSON data using
-
Response JSON Object:
- A response JSON object is constructed containing a message stating
"Data received successfully"
, along with the receivedtemperature
andhumidity
values. This response confirms to the client that the data was received and processed.
- A response JSON object is constructed containing a message stating
-
Response Return:
return jsonify(res), 200
sends the response back to the client. Thejsonify
function from Flask converts the Python dictionary into a JSON response. The200
HTTP status code indicates that the request has been processed successfully.
- Running the Server:
if __name__ == '__main__': app.run(host='0.0.0.0', port=5000)
- This condition ensures that the Flask server runs directly when the script is executed, not when imported as a module.
host='0.0.0.0'
tells the server to be accessible externally, not just locally. It listens on all network interfaces.port=5000
specifies that the server will be accessible on TCP port 5000, which is the default port for Flask development servers.