From b406cb5b9ee43ec8c702c2f2cae8b1cb504cf8c3 Mon Sep 17 00:00:00 2001
From: "Wortman, Elliot (UG - Comp Sci & Elec Eng)" <ew00710@surrey.ac.uk>
Date: Thu, 30 Nov 2023 22:17:47 +0000
Subject: [PATCH] Write to database every 6 hours
---
db_sqlite.py | 47 ++++++++++++++++++++++++-----------------------
1 file changed, 24 insertions(+), 23 deletions(-)
diff --git a/db_sqlite.py b/db_sqlite.py
index 1743cd0..a6008a6 100644
--- a/db_sqlite.py
+++ b/db_sqlite.py
@@ -1,48 +1,49 @@
import sqlite3
import json
+from datetime import datetime, timedelta
DB_FILE = "measurements.db"
-def insert_measurement(input_values):
- """ Insert values into the database and fetch the latest entry """
+def insert_measurement(input_values, time_limit=True):
+ """ Insert values into the database with a timestamp.
+ Only insert if it's been at least 6 hours since the last entry. """
try:
# Create a database connection
conn = sqlite3.connect(DB_FILE)
cursor = conn.cursor()
- # Create table if it doesn't exist
+ # Create table if it doesn't exist with an additional time_modified column
cursor.execute('''CREATE TABLE IF NOT EXISTS measurements (
nitrogen INTEGER,
phosphorus INTEGER,
potassium INTEGER,
temperature INTEGER,
humidity INTEGER,
- moisture INTEGER
+ moisture INTEGER,
+ time_modified TEXT
);''')
- # Insert new values
+ # Check the time of the last entry
+ cursor.execute(
+ "SELECT time_modified FROM measurements ORDER BY rowid DESC LIMIT 1;")
+ last_entry = cursor.fetchone()
+
+ if time_limit and last_entry:
+ last_time = datetime.strptime(
+ last_entry[0], '%Y-%m-%dT%H:%M:%S.%fZ')
+ if datetime.utcnow() - last_time < timedelta(hours=6):
+ return False
+
+ # Insert new values with current UTC timestamp
cursor.execute('''INSERT INTO measurements
- (nitrogen, phosphorus, potassium, temperature, humidity, moisture)
- VALUES (?, ?, ?, ?, ?, ?)''', input_values)
+ (nitrogen, phosphorus, potassium, temperature, humidity, moisture, time_modified)
+ VALUES (?, ?, ?, ?, ?, ?, strftime('%Y-%m-%dT%H:%M:%fZ', 'now'))''', input_values)
conn.commit()
- # Fetch the latest entry
- cursor.execute(
- "SELECT * FROM measurements ORDER BY rowid DESC LIMIT 1;")
- row = cursor.fetchone()
-
# Close the connection
conn.close()
-
- # Process and return the result
- if row:
- column_names = ['nitrogen', 'phosphorus',
- 'potassium', 'temperature', 'humidity', 'moisture']
- data = dict(zip(column_names, row))
- return json.dumps(data, indent=4)
- else:
- return json.dumps({})
+ return True
except sqlite3.Error as e:
print(e)
@@ -57,9 +58,9 @@ def read_latest_entry_as_json():
conn = sqlite3.connect(DB_FILE)
cursor = conn.cursor()
- # Fetch the latest entry
+ # Fetch the latest entry excluding the time_modified column
cursor.execute(
- "SELECT * FROM measurements ORDER BY rowid DESC LIMIT 1;")
+ "SELECT nitrogen, phosphorus, potassium, temperature, humidity, moisture FROM measurements ORDER BY rowid DESC LIMIT 1;")
row = cursor.fetchone()
# Close the connection
--
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