succd: split out http server, daemon state, daemon controller

This improves the structure of the code, separating the data/control
interface out and then implementing the http interface as a user of this
interface.

succbone/succd/process.go

@@ -4,21 +4,18 @@ import (
 	"context"
 	"errors"
 	"fmt"
-	"math"
 	"sync"
 	"time"
 
 	"k8s.io/klog"
 )
 
-// daemon is the main state of the succdaemon.
+// daemon is the main service of the succdaemon.
 type daemon struct {
 	// adcPirani is the adc implementation returning the voltage of the Pfeiffer
 	// Pirani gauge.
 	adcPirani adc
 
-	safety safetyStatus
-
 	gpioDiffusionPump gpio
 	gpioRoughingPump  gpio
 	gpioBtnPumpDown   gpio
@@ -26,27 +23,9 @@ type daemon struct {
 	gpioBelowRough    gpio
 	gpioBelowHigh     gpio
 
-	// mu guards state variables below.
+	// mu guards the state below.
 	mu sync.RWMutex
-	// adcPiraniVolts is a moving window of read ADC values, used to calculate a
-	// moving average.
-	adcPiraniVolts []float32
-	rpOn           bool
-	dpOn           bool
-
-	vent       momentaryOutput
-	pumpdown   momentaryOutput
-	aboveRough thresholdOutput
-	aboveHigh  thresholdOutput
-}
-
-type safetyStatus struct {
-	// failsafe mode is enabled when the pirani gauge appears to be
-	// disconnected, and is disabled only when an atmosphere is read.
-	failsafe bool
-	// highPressure mode is enabled when the pressure reading is above 1e-1
-	// mbar, locking out the diffusion pump from being enabled.
-	highPressure bool
+	daemonState
 }
 
 // momentaryOutput is an output that can be triggered for 500ms.
@@ -127,7 +106,7 @@ func (d *daemon) processOnce(_ context.Context) error {
 	d.pumpdown.process()
 	d.vent.process()
 
-	_, mbar := d.piraniUnlocked()
+	_, mbar := d.daemonState.pirani()
 	d.aboveRough.process(float64(mbar))
 	d.aboveHigh.process(float64(mbar))
 
@@ -201,116 +180,3 @@ func (d *daemon) processOnce(_ context.Context) error {
 
 	return nil
 }
-
-type piraniDetection uint
-
-const (
-	// piraniDetectionUnknown means the system isn't yet sure whether the pirani
-	// gauge is connected.
-	piraniDetectionUnknown piraniDetection = iota
-	// piraniDetectionConnected means the system assumes the pirani gauge is
-	// connected.
-	piraniDetectionConnected = iota
-	// piraniDetectionDisconnected means the system assumes the pirani gauge is
-	// disconnected.
-	piraniDetectionDisconnected = iota
-)
-
-// piraniDetection guesses whether the pirani gauge is connected.
-func (d *daemon) piraniDetection() piraniDetection {
-	if len(d.adcPiraniVolts) < 3 {
-		return piraniDetectionUnknown
-	}
-	volts := float32(0.0)
-	for _, v := range d.adcPiraniVolts[len(d.adcPiraniVolts)-3:] {
-		volts += v
-	}
-	volts /= 3.0
-
-	bar := math.Pow(10.0, float64(volts)-8.5)
-	mbar := float32(bar * 1000.0)
-
-	if mbar < 4e-6 {
-		return piraniDetectionDisconnected
-	}
-	return piraniDetectionConnected
-}
-
-// pirani returns the Pirani gauge voltage and pressure.
-func (d *daemon) pirani() (volts float32, mbar float32) {
-	d.mu.RLock()
-	volts, mbar = d.piraniUnlocked()
-	d.mu.RUnlock()
-	return
-}
-
-func (d *daemon) piraniUnlocked() (volts float32, mbar float32) {
-	volts = 0.0
-	for _, v := range d.adcPiraniVolts {
-		volts += v
-	}
-	if len(d.adcPiraniVolts) != 0 {
-		volts /= float32(len(d.adcPiraniVolts))
-	}
-
-	// Per Pirani probe docs.
-	bar := math.Pow(10.0, float64(volts)-8.5)
-	mbar = float32(bar * 1000.0)
-	return
-}
-
-// rpSet enables/disables the roughing pump.
-func (d *daemon) rpSet(state bool) {
-	d.mu.Lock()
-	defer d.mu.Unlock()
-	d.rpOn = state
-}
-
-// rpGet returns whether the roughing pump is enabled/disabled.
-func (d *daemon) rpGet() bool {
-	d.mu.RLock()
-	defer d.mu.RUnlock()
-	return d.rpOn
-}
-
-// dpSet enables/disables the diffusion pump.
-func (d *daemon) dpSet(state bool) {
-	d.mu.Lock()
-	defer d.mu.Unlock()
-	d.dpOn = state
-}
-
-// dpGet returns whether the diffusion pump is enabled/disabled.
-func (d *daemon) dpGet() bool {
-	d.mu.RLock()
-	defer d.mu.RUnlock()
-	return d.dpOn
-}
-
-func (d *daemon) vacuumStatusGet() (rough, high bool) {
-	d.mu.RLock()
-	defer d.mu.RUnlock()
-	rough = !d.aboveRough.output
-	high = !d.aboveHigh.output
-	return
-}
-
-func (d *daemon) safetyStatusGet() safetyStatus {
-	d.mu.RLock()
-	defer d.mu.RUnlock()
-	return d.safety
-}
-
-// pumpDownPressed toggles the pump down relay for 500ms.
-func (d *daemon) pumpDownPress() {
-	d.mu.Lock()
-	defer d.mu.Unlock()
-	d.pumpdown.trigger()
-}
-
-// ventPress toggles the vent relay for 500ms.
-func (d *daemon) ventPress() {
-	d.mu.Lock()
-	defer d.mu.Unlock()
-	d.vent.trigger()
-}