From df922fcdba4a5e96cb72b8238e1999de970fe6fb Mon Sep 17 00:00:00 2001
From: Daniel Bulant <danbulant@gmail.com>
Date: Sun, 8 Mar 2026 23:58:52 +0100
Subject: [PATCH] initial api version of a5

---
 a5/.python-version |  1 +
 a5/README.md       |  0
 a5/db.py           | 91 ++++++++++++++++++++++++++++++++++++++++++++++
 a5/main.py         | 63 ++++++++++++++++++++++++++++++++
 a5/pyproject.toml  |  7 ++++
 5 files changed, 162 insertions(+)
 create mode 100644 a5/.python-version
 create mode 100644 a5/README.md
 create mode 100644 a5/db.py
 create mode 100644 a5/main.py
 create mode 100644 a5/pyproject.toml

diff --git a/a5/.python-version b/a5/.python-version
new file mode 100644
index 0000000..24ee5b1
--- /dev/null
+++ b/a5/.python-version
@@ -0,0 +1 @@
+3.13
diff --git a/a5/README.md b/a5/README.md
new file mode 100644
index 0000000..e69de29
diff --git a/a5/db.py b/a5/db.py
new file mode 100644
index 0000000..b5c3da2
--- /dev/null
+++ b/a5/db.py
@@ -0,0 +1,91 @@
+import sqlite3
+from contextlib import closing
+from typing import List
+
+
+class Stats:
+    """Holds statistics of measurements"""
+
+    tvoc_max: sqlite3.Row | None
+    tvoc_min: sqlite3.Row | None
+    co2_min: sqlite3.Row | None
+    co2_max: sqlite3.Row | None
+
+
+class DB:
+    """Class for handling database interactions"""
+
+    # sql
+    CREATE_SQL = """
+CREATE TABLE IF NOT EXISTS measurements
+    (
+        timestamp integer not null primary key,
+        tvoc real not null,
+        co2 real not null
+    );
+"""
+
+    def __init__(self, db_name: str = "greetings.db"):
+        """Class init"""
+        self.db_name = db_name
+        self._conn = sqlite3.connect(
+            self.db_name, detect_types=sqlite3.PARSE_DECLTYPES | sqlite3.PARSE_COLNAMES
+        )
+        self._conn.row_factory = sqlite3.Row
+        cursor = self._conn.cursor()
+        cursor.execute(self.CREATE_SQL)
+        self._conn.commit()
+
+    def store(self, timestamp: int, tvoc: float, co2: float) -> int | None:
+        """Adds a measurement"""
+        with closing(self._conn.cursor()) as cursor:
+            cursor.execute(
+                # sql
+                "INSERT INTO measurements (timestamp, tvoc, co2) VALUES (?, ?, ?)",
+                (timestamp, tvoc, co2),
+            )
+            self._conn.commit()
+            return cursor.lastrowid
+
+    def get_stats(self) -> Stats:
+        """Returns measurement statistics"""
+        with closing(self._conn.cursor()) as cursor:
+            # this could probably be made into a single query, but the database being sqlite results in much lower latency with multiple selects
+            # returned object could also be better typed
+            stats = Stats()
+            cursor.execute(
+                # sql
+                "SELECT tvoc, timestamp FROM measurements ORDER BY tvoc DESC LIMIT 1"
+            )
+            stats.tvoc_max = cursor.fetchone()
+            cursor.execute(
+                # sql
+                "SELECT tvoc, timestamp FROM measurements ORDER BY tvoc ASC LIMIT 1"
+            )
+            stats.tvoc_min = cursor.fetchone()
+            cursor.execute(
+                # sql
+                "SELECT co2, timestamp FROM measurements ORDER BY co2 DESC LIMIT 1"
+            )
+            stats.co2_max = cursor.fetchone()
+            cursor.execute(
+                # sql
+                "SELECT co2, timestamp FROM measurements ORDER BY co2 ASC LIMIT 1"
+            )
+            stats.co2_min = cursor.fetchone()
+            return stats
+
+    def get_page(self, page: int, page_size: int = 20) -> List[sqlite3.Row]:
+        """Gets a paged list of all measurements. Page is 0 indexed."""
+        with closing(self._conn.cursor()) as cur:
+            cur = self._conn.cursor()
+            cur.execute(
+                # sql
+                "SELECT timestamp, tvoc, co2 FROM measurements ORDER BY timestamp DESC LIMIT ?, ?",
+                (page_size, page * page_size),
+            )
+            return cur.fetchall()
+
+    def close(self) -> None:
+        """Closes the DB connection"""
+        self._conn.close()
diff --git a/a5/main.py b/a5/main.py
new file mode 100644
index 0000000..2126fd6
--- /dev/null
+++ b/a5/main.py
@@ -0,0 +1,63 @@
+from flask import Flask, g, redirect, render_template, request, url_for
+from werkzeug.wrappers.response import Response
+
+from db import DB
+
+app = Flask(__name__)
+
+
+@app.route("/api/report", methods=["POST"])
+def report() -> str | Response:
+    """Adds a measurement"""
+    timestamp = request.form["timestamp"]
+    tvoc = request.form["tvoc"]
+    co2 = request.form["co2"]
+    try:
+        timestamp = int(timestamp)
+        tvoc = float(tvoc)
+        co2 = float(co2)
+    except ValueError:
+        return "Invalid data", 400
+    db = get_db()
+    db.store(timestamp, tvoc, co2)
+    return "ok", 200
+
+
+@app.route("/api/stats", methods=["GET"])
+def stats() -> Response:
+    db = get_db()
+    return db.get_stats()
+
+
+@app.route("/api/measurements", methods=["GET"])
+def measurements() -> Response:
+    db = get_db()
+    page = request.get["page"]
+    page_size = 20
+    try:
+        page = int(page)
+        if page < 0:
+            raise ValueError()
+    except ValueError:
+        return "Invalid page", 400
+    return db.get_page(page, page_size)
+
+
+def get_db() -> DB:
+    """gets database connection"""
+    db_instance = getattr(g, "_database", None)
+    if db_instance is None:
+        db_instance = g._database = DB()
+    return db_instance
+
+
+@app.teardown_appcontext
+def close_connection(_exception):
+    """disconnects database on connection close (if opened)"""
+    db_instance = getattr(g, "_database", None)
+    if db_instance is not None:
+        db_instance.close()
+
+
+if __name__ == "__main__":
+    app.run(debug=True)
diff --git a/a5/pyproject.toml b/a5/pyproject.toml
new file mode 100644
index 0000000..6a0cb92
--- /dev/null
+++ b/a5/pyproject.toml
@@ -0,0 +1,7 @@
+[project]
+name = "a5"
+version = "0.1.0"
+description = "Sensor driven website"
+readme = "README.md"
+requires-python = ">=3.13"
+dependencies = []