config.json

{
  "device_id": "your_device_id",
  "database": {
    "database": "your_database",
    "user": "your_user",
    "password": "your_password",
    "host": "your_host",
    "port": "your_port"
  }
}


------------------------------------------------------------

postPartial.py

import psycopg2
from psycopg2 import sql
import json

def connect_to_database(database, user, password, host, port):
    """Establishes a connection to the PostgreSQL database."""
    try:
        conn = psycopg2.connect(
            database=database,
            user=user,
            password=password,
            host=host,
            port=port
        )
        return conn
    except psycopg2.Error as e:
        print("Failed to connect to the database:", e)
        return None

def get_last_entry(device_id, conn):
    """Retrieves the last entry from the device's database."""
    try:
        cursor = conn.cursor()
        query = sql.SQL("SELECT * FROM {} ORDER BY id DESC LIMIT 1").format(sql.Identifier(device_id))
        cursor.execute(query)
        last_entry = cursor.fetchone()
        cursor.close()
        return last_entry
    except psycopg2.Error as e:
        print("Error retrieving last entry:", e)
        return None

def backup_data(device_id, last_entry, conn):
    """Backs up the new data entries since the last backup."""
    try:
        cursor = conn.cursor()
        query = sql.SQL("SELECT * FROM {} WHERE id > %s").format(sql.Identifier(device_id))
        cursor.execute(query, (last_entry[0],))
        new_entries = cursor.fetchall()
        cursor.close()
        return new_entries
    except psycopg2.Error as e:
        print("Error backing up data:", e)
        return []

def compress_data(data):
    """Compresses the data using a suitable compression algorithm."""
    # TODO: Compression logic here
    return compressed_data

def send_to_central_server(compressed_data):
    """Sends the compressed data to the central server."""
    # TODO: Sending logic here
    pass

def load_config(filename):
    """Loads the configuration from a JSON file."""
    try:
        with open(filename, 'r') as file:
            config = json.load(file)
            return config
    except FileNotFoundError:
        print(f"Configuration file '{filename}' not found.")
        return None
    except json.JSONDecodeError as e:
        print(f"Error parsing configuration file: {e}")
        return None

# Load configuration from JSON file
config = load_config('config.json')
if not config:
    exit()

# Retrieve configuration values
device_id = config.get('device_id')
database_config = config.get('database')

# Connect to the database
conn = connect_to_database(**database_config)
if not conn:
    exit()

# Get the last entry
last_entry = get_last_entry(device_id, conn)
if not last_entry:
    conn.close()
    exit()

# Backup new data
new_entries = backup_data(device_id, last_entry, conn)
if not new_entries:
    conn.close()
    exit()

# Compress the data
compressed_data = compress_data(new_entries)

# Send data to central server
send_to_central_server(compressed_data)

# Close the connection
conn.close()