From 591097e5a3741432e2acd9c41fadd4eb10678674 Mon Sep 17 00:00:00 2001
From: xengineering <mail2xengineering@protonmail.com>
Date: Tue, 15 Jun 2021 16:44:15 +0200
Subject: Refactoring: Make Statemachine reusable
---
src/camera.go | 16 ++++++++++++++++
src/state.go | 33 ++++++++++++---------------------
2 files changed, 28 insertions(+), 21 deletions(-)
(limited to 'src')
diff --git a/src/camera.go b/src/camera.go
index 12a9d54..197aa21 100644
--- a/src/camera.go
+++ b/src/camera.go
@@ -2,6 +2,10 @@
package main
+import (
+ "time"
+)
+
type Camera struct {
statemachine Machine
}
@@ -29,10 +33,22 @@ func NewCamera() Camera {
},
api: make(chan string),
state_listeners: make([]*(chan string), 0),
+ hook: runCameraHooks,
},
}
}
+func runCameraHooks(last string, next string) {
+
+ if last == "idle" && next == "single_picture" {
+ // TODO implement launch of python subprocess here
+ go func() {
+ time.Sleep(1 * time.Second)
+ camera.statemachine.SendEvent("single_picture_taken")
+ }()
+ }
+}
+
func (cam *Camera) run() {
cam.statemachine.Run()
}
diff --git a/src/state.go b/src/state.go
index 5970ba8..10c35ef 100644
--- a/src/state.go
+++ b/src/state.go
@@ -4,7 +4,6 @@ package main
import (
"log"
- "time"
)
// This struct represents the statemachine.
@@ -15,6 +14,7 @@ type Machine struct {
states StateMap
api chan string
state_listeners []*(chan string)
+ hook HookFunction
}
type StateMap map[string]MachineState
@@ -29,6 +29,8 @@ type MachineTransition struct {
to string
}
+type HookFunction func(string, string)
+
// This will run the statemachine (blocking).
func (m *Machine) Run() {
var event string
@@ -100,28 +102,17 @@ func (m *Machine) deregisterListener(listener *(chan string)) {
func (m *Machine) processEvent(event string) string {
current := m.GetState()
next := m.states[current].on[event].to
- if next != "" {
+ if next != "" { // check if transition is possible
log.Printf("State machine '%s' changes from '%s' to '%s'\n", m.name, current, next)
- m.current = next
- m.runHooks(current, next)
- return next
- }
- return current
-}
-// In this function one can implement callback functions
-// which will be triggered on certain transitions.
-func (m *Machine) runHooks(last string, next string) {
-
- for _,listener := range(m.state_listeners) {
- *listener <- next
- }
+ // inform all state listeners
+ for _,listener := range(m.state_listeners) {
+ *listener <- next
+ }
- if last == "idle" && next == "single_picture" {
- // TODO implement launch of python subprocess here
- go func() {
- time.Sleep(1 * time.Second)
- m.SendEvent("single_picture_taken")
- }()
+ m.hook(current, next) // execute registered callback function
+ m.current = next // set new state
+ return next
}
+ return current
}
--
cgit v1.2.3-70-g09d2