Switch pump to class

library/grow/pump.py

@@ -1,78 +1,63 @@
 import time
 import atexit
+import threading
 import RPi.GPIO as GPIO
 
 PUMP_1_PIN = 17
 PUMP_2_PIN = 27
 PUMP_3_PIN = 22
-
-_is_setup = False
+PUMP_PWM_FREQ = 10000
+PUMP_MAX_DUTY = 60
 
 
 class Pump(object):
-    __slots__ = 'out1', 'out2', 'out3'
+    def __init__(self, channel):
+        self._gpio_pin = [PUMP_1_PIN, PUMP_2_PIN, PUMP_3_PIN][channel]
 
-    def __init__(self, out1, out2, out3):
-        self.out1 = out1
-        self.out2 = out2
-        self.out3 = out3
+        GPIO.setmode(GPIO.BCM)
+        GPIO.setwarnings(False)
+        GPIO.setup(self._gpio_pin, GPIO.OUT, initial=GPIO.LOW)
+        self._pwm = GPIO.PWM(self._gpio_pin, PUMP_PWM_FREQ)
+        self._pwm.start(0)
 
-    def __repr__(self):
-        fmt = """Pump 1: {out1}
-Pump 1: {out2} Ohms
-Pump 1: {out3} Ohms"""
-        
-        return fmt.format(
-            out1=self.out1,
-            out2=self.out2,
-            out3=self.out3)
+        self._timeout = None
 
-    __str__ = __repr__
+    def set_speed(self, speed):
+        """Set pump speed (PWM duty cycle)."""
+        if speed > 1.0 or speed < 0:
+            raise ValueError("Speed must be between 0 and 1")
+        self._pwm.ChangeDutyCycle(int(PUMP_MAX_DUTY * speed))
+        self._speed = speed
 
+    def get_speed(self):
+        """Return Pump speed (PWM duty cycle)."""
+        return self._speed
 
-def setup():
-    global _is_setup
-    global _pump
-    
-    if _is_setup:
-        return
-    _is_setup = True
+    def stop(self):
+        """Stop the pump."""
+        self.set_speed(0)
 
-    GPIO.setwarnings(False)
-    GPIO.setmode(GPIO.BCM)
-    GPIO.setup(PUMP_1_PIN, GPIO.OUT)
-    GPIO.input(PUMP_1_PIN, 0)
-    GPIO.setup(PUMP_2_PIN, GPIO.OUT)
-    GPIO.input(PUMP_2_PIN, 0)
-    GPIO.setup(PUMP_3_PIN, GPIO.OUT)
-    GPIO.input(PUMP_3_PIN, 0)
-    
-    atexit.register(cleanup)
+    def pulse(self, speed, timeout=0.1, blocking=True, force=False):
+        """Pulse the pump for timeout seconds.
 
+        :param timeout: Timeout, in seconds, of the pump pulse
+        :param blocking: If true, function will block until pump has stopped
 
-def set_pump_on(channel):
-    """Set wet point for a moisture channel."""
-    _pump[channel] = 1
+        """
+        if blocking:
+            self.set_speed(speed)
+            time.sleep(timeout)
+            self.stop()
+            return True
+        else:
+            if self._timeout is not None:
+                if self._timeout.is_alive():
+                    if force:
+                        self._timeout.cancel()
+                    else:
+                        return False
+            self._timeout = threading.Timer(timeout, self.stop)
+            self.set_speed(speed)
+            self._timeout.start()
+            return True
 
-def set_pump_off(channel, value):
-    """Set wet point for a moisture channel."""
-    _pump[channel] = 0
-
-def read_pump(channel):
-    """Get current value for the additional ADC pin."""
-    setup()
-    return _pump[channel]
-
-def cleanup():
-    GPIO.output(PUMP_1_PIN, 0)
-    GPIO.output(PUMP_2_PIN, 0)
-    GPIO.output(PUMP_3_PIN, 0)
-
-def read_all():
-    """Return pump state"""
-    setup()
-    in1 = _pump[1]
-    in2 = _pump[2]
-    in3 = _pump[3]
-
-    return _pump(in1, in2, in3)