Init repo with first working version

.gitignore

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+config.json
+__pycache__
+*.swp
+venv

config.example.json

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+{
+    "db_user": "",
+    "db_passwd": "",
+    "db_host": "localhost",
+    "db_port": 3306,
+    "db_db": "",
+    "db_table": "water_level_elbe_dresden",
+    "sleep_sec": 600,
+    "url": "https://www.umwelt.sachsen.de/umwelt/infosysteme/hwims/portal/web/wasserstand-pegel-501060"
+}

main.py

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+import json
+import mariadb
+import sys
+import time
+from urllib.request import urlopen
+from bs4 import BeautifulSoup
+from datetime import datetime
+
+
+def read_config(file="config.json"):
+    """
+    Read config file to get database configuration and other stuff.
+    """
+    with open(file, "r") as f:
+        config = json.load(f)
+    return config
+
+
+def prepare_db():
+    """
+    Setup database table, if it not exists.
+    """
+    try:
+        conn = mariadb.connect(
+            user=config["db_user"],
+            password=config["db_passwd"],
+            host=config["db_host"],
+            port=config["db_port"],
+            database=config["db_db"]
+        )
+    except mariadb.Error as e:
+        print(f"Error connecting to MariaDB Platform: {e}")
+        sys.exit(1)
+
+    cur = conn.cursor()
+    cur.execute("SHOW TABLES")
+
+    table_exists = False
+    for table in cur:
+        if table == config["db_table"]:
+            table_exists = True
+
+    if not table_exists:
+        cur.execute("CREATE TABLE ? (timestamp TIMESTAMP PRIMARY KEY, level_cm INT, flow_m3_s INT)", (config["db_table"]))
+
+    conn.close()
+
+
+def write_db(timestamp, level: int, flow: int):
+    """
+    Write data set to database.
+    @param timestamp: timestamp of data set
+    @param level: water level in cm
+    @param flow: water flow in m3/s
+    """
+    try:
+        conn = mariadb.connect(
+            user=config["db_user"],
+            password=config["db_passwd"],
+            host=config["db_host"],
+            port=config["db_port"],
+            database=config["db_db"]
+        )
+    except mariadb.Error as e:
+        print(f"Error connecting to MariaDB Platform: {e}")
+        sys.exit(1)
+
+    cur = conn.cursor()
+    try:
+        cur.execute("INSERT INTO ? (timestamp,level_cm,flow_m3_s) VALUES (?, ?, ?)", (config["db_table"], timestamp, level, flow))
+    except mariadb.Error as e:
+        print(f"Error: {e}")
+    finally:
+        conn.close()
+
+
+def retrieve(url: str):
+    """
+    Get webpage and parse it to get timestamp, water level and flow.
+    @param url: the URL to call
+    @return: 3-tuple with timestamp, level, flow
+    """
+    page = urlopen(url)
+    html = page.read().decode("utf-8")
+    soup = BeautifulSoup(html, "html.parser")
+
+    latest = soup.select(".quickbarTable tbody")[0].select("tr")[0]
+    latest_ts = latest.select("td")[0].text
+    ts = datetime.strptime(latest_ts.strip(), "%d.%m.%Y %H:%M")
+    latest_level = latest.select("td")[1].text
+    latest_flow = latest.select("td")[2].text
+
+    return ts, int(latest_level), int(latest_flow)
+
+
+config = read_config()
+# prepare_db()
+while True:
+    ts, latest_level, latest_flow = retrieve(config["url"])
+    # write_db(ts, latest_level, latest_flow)
+    print(str(ts) + ": " + str(latest_level) + "cm " + str(latest_flow) + "m3/s")
+    time.sleep(config["sleep_sec"])

requirements.txt

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+beautifulsoup4==4.12.3
+mariadb==1.1.9