Improved readability

This reverts commit 9715339c43.

requirements.txt

@@ -4,4 +4,5 @@ fastapi
 uvicorn
 fastapi-cors
 Adafruit_DHT
-requests
+requests
+mh_z19

src/actions.py

@@ -5,30 +5,34 @@ from config import climate_log_file, dht22_pin
 
 from handler.dht22_climate import Dht22Climate
 from handler.matrix_display import MatrixDisplay
+from handler.mhz19_co2 import Mhz19Co2
 
 
 climate_sensor = Dht22Climate(dht22_pin)
+co2_sensor = Mhz19Co2()
 matrix_display = MatrixDisplay()
 
 
-async def log_temperature():
+async def log_climate(delay_sec: int = 60):
     # If file does not exist, create it and write header
     if not os.path.isfile(climate_log_file):
         with open(climate_log_file, "w") as f:
-            f.write("timestamp,temperature,humidity\n")
+            f.write("timestamp,temperature,humidity,co2\n")
 
     while True:
         measurements = climate_sensor.read()
+        co2_density = co2_sensor.read()
         if measurements is not None:
             with open(climate_log_file, "a") as f:
                 f.write(
-                    "{},{},{}\n".format(
+                    "{},{},{},{}\n".format(
                         datetime.now().isoformat(),
                         measurements["temperature"],
                         measurements["humidity"],
+                        co2_density,
                     )
                 )
-        await asyncio.sleep(60)
+        await asyncio.sleep(delay_sec)
 
 
 async def display_time():

src/handler/dht22_climate.py

@@ -8,12 +8,12 @@ class Dht22Climate:
         self.pin = pin
         self.last_read = None
 
-    def get_last_read(self):
+    def get_last_read(self) -> dict | None:
         if self.last_read is None:
             return self.read()
         return self.last_read
 
-    def read(self):
+    def read(self) -> dict | None:
         humidity, temperature = Adafruit_DHT.read_retry(self.sensor, self.pin)
         if humidity is not None and temperature is not None:
             self.last_read = {"temperature": temperature, "humidity": humidity}

src/handler/mhz19_co2.py

@@ -0,0 +1,48 @@
+import serial
+
+
+class Mhz19Co2:
+    def __init__(self):
+        self.last_read = None
+
+        self.serial_port = "/dev/serial0"
+        self.baud_rate = 9600
+        self.byte_size = 8
+        self.parity = "N"
+        self.stop_bits = 1
+        self.timeout = None
+
+    def get_last_read(self) -> int | None:
+        if self.last_read is None:
+            return self.read()
+        return self.last_read
+
+    def read(self) -> int | None:
+        ser = None
+        try:
+            ser = serial.Serial(
+                port=self.serial_port,
+                baudrate=self.baud_rate,
+                bytesize=self.byte_size,
+                parity=self.parity,
+                stopbits=self.stop_bits,
+                timeout=self.timeout,
+            )
+
+            # send "Read CO2" command
+            command_data = bytes([0xFF, 0x01, 0x86, 0x00, 0x00, 0x00, 0x00, 0x00, 0x79])
+            ser.write(command_data)
+
+            # read "Return Value (CO2 concentration)"
+            data = ser.read(9)
+            concentration = data[2] * 256 + data[3]
+
+        except Exception as e:
+            print(f"Error reading data: {e}")
+        finally:
+            if ser:
+                ser.close()
+                ser = None
+
+        self.last_read = concentration
+        return concentration

src/main.py

@@ -8,9 +8,9 @@ from fastapi.middleware.cors import CORSMiddleware
 from actions import (
     climate_sensor,
     display_time,
-    log_temperature,
     matrix_display,
     display_pattern,
+    co2_sensor,
 )
 from config import climate_log_file
 from handler.action_queue import ActionQueue
@@ -20,7 +20,6 @@ logging.getLogger().setLevel(logging.INFO)
 
 
 # Start services
-asyncio.create_task(log_temperature())
 queue = ActionQueue(matrix_display.show_current_time)
 app = FastAPI()
 
@@ -62,7 +61,7 @@ async def turn_off():
 
 @app.post("/temperature")
 async def temperature():
-    measurements = climate_sensor.get_last_read()
+    measurements = climate_sensor.read()
     if measurements is None:
         return {"message": "Failed to read temperature"}
 
@@ -75,7 +74,7 @@ async def temperature():
 
 @app.post("/humidity")
 async def humidity():
-    measurements = climate_sensor.get_last_read()
+    measurements = climate_sensor.read()
     if measurements is None:
         return {"message": "Failed to read humidity"}
 
@@ -86,6 +85,30 @@ async def humidity():
     return measurements
 
 
+@app.post("/co2")
+async def co2():
+    co2 = co2_sensor.read()
+    if co2 is None:
+        return {"message": "Failed to read co2"}
+
+    await queue.add_action_to_queue(matrix_display.show_text, f"{co2} ppm")
+
+    return {"co2": co2}
+
+
+@app.post("/climate")
+async def climate():
+    measurements = climate_sensor.read()
+    if measurements is None:
+        return {"message": "Failed to read humidy and temperature"}
+
+    co2 = co2_sensor.read()
+    if co2 is None:
+        return {"message": "Failed to read co2"}
+
+    return {"co2": co2, **measurements}
+
+
 @app.post("/history")
 async def history():
     day_entry_count = 24 * 60

start.sh

@@ -1,3 +0,0 @@
-cd /home/pi/matrix-clock/src
-
-uvicorn main:app --reload --host 0.0.0.0