Add debug variable to save a live fsm graph

2 files changed, 84 insertions, 11 deletions

diff --git a/src/fsm.go b/src/fsm.go
index 9978fde..2b61cda 100644
--- a/src/fsm.go
+++ b/src/fsm.go
@@ -2,6 +2,7 @@ package eduvpn
 
 import (
 	"errors"
+	"os"
 )
 
 type FSMStateID int8
@@ -152,18 +153,84 @@ func (eduvpn *VPNState) HasTransition(check FSMStateID) bool {
 	return ok && fsm != nil
 }
 
+func (eduvpn *VPNState) InState(check FSMStateID) bool {
+	fsm := FindFSMState(check, eduvpn.FSM)
+
+	if fsm == nil {
+		return false
+	}
+
+	return fsm.Current == check
+}
+
+func (eduvpn *VPNState) writeGraph() {
+	graph := eduvpn.GenerateGraph()
+
+	f, err := os.Create("debug.graph")
+
+	if err != nil {
+		panic(err)
+	}
+
+	defer f.Close()
+
+	f.WriteString(graph)
+}
+
 func (eduvpn *VPNState) GoTransition(newState FSMStateID, data string) bool {
 	fsm, ok := eduvpn.findTransition(newState)
 
 	if ok {
 		oldState := fsm.Current
 		fsm.Current = newState
+		if eduvpn.Debug {
+			eduvpn.writeGraph()
+		}
 		eduvpn.StateCallback(oldState.String(), newState.String(), data)
 	}
 
 	return ok
 }
 
+func getGraphviz(fsm *FSM, graph string) string {
+	if fsm == nil {
+		return graph
+	}
+
+	for name, state := range fsm.States {
+		for _, transition := range state.Transition {
+			graph += "\n" + "cluster_" + name.String() + " -> cluster_" + transition.String()
+		}
+
+		graph += "\nsubgraph cluster_" + name.String() + "{\n"
+		if (state.Locked) {
+			graph += "style=\"dotted\"\n"
+		} else {
+			graph += "style=\"\"\n"
+		}
+		if (fsm.Current == name) {
+			graph += "color=\"blue\"\n"
+			graph += "fontcolor=\"blue\"\n"
+		} else {
+			graph += "color=\"\"\n"
+			graph += "fontcolor=\"\"\n"
+		}
+		graph += "label=" + name.String()
+		graph = getGraphviz(state.Sub, graph)
+		graph += "\n}"
+	}
+	return graph
+}
+
+func (eduvpn *VPNState) GenerateGraph() string {
+	graph := "digraph fsm {\n"
+	graph += "nodesep=2"
+	graph = getGraphviz(eduvpn.FSM, graph)
+	graph += "\n}"
+
+	return graph
+}
+
 func (eduvpn *VPNState) InitializeFSM() {
 	// The states when a server is authenticated
 	serverAuthenticated := &FSMState{Sub: &FSM{States: FSMStates{
diff --git a/src/state.go b/src/state.go
index aa31513..ec927f9 100644
--- a/src/state.go
+++ b/src/state.go
@@ -19,29 +19,36 @@ type VPNState struct {
 	// The file we keep open for logging
 	LogFile *FileLogger `json:"-"`
 
+	// The fsm
 	FSM *FSM `json:"-"`
+
+	// Whether to enable debugging
+	Debug bool `json:"-"`
 }
 
-func (state *VPNState) Register(name string, directory string, stateCallback func(string, string, string)) error {
-	if state.FSM == nil {
-		state.InitializeFSM()
-	}
+func (state *VPNState) Register(name string, directory string, stateCallback func(string, string, string), debug bool) error {
+	state.InitializeFSM()
 	if !state.HasTransition(APP_REGISTERED) {
 		return errors.New("app already registered")
 	}
 	state.Name = name
 	state.ConfigDirectory = directory
 	state.StateCallback = stateCallback
+	state.Debug = debug
 
-	// Initialize the logger
-	// state.InitLog(LOG_WARNING)
+	LogLevel := LOG_WARNING
 
-	// state.Log(LOG_INFO, "App registered")
+	if debug {
+		LogLevel = LOG_INFO
+	}
+
+	// Initialize the logger
+	state.InitLog(LogLevel)
 
 	// Try to load the previous configuration
 	if state.LoadConfig() != nil {
 		// This error can be safely ignored, as when the config does not load, the struct will not be filled
-		// state.Log(LOG_INFO, "Previous configuration not found")
+		state.Log(LOG_INFO, "Previous configuration not found")
 	}
 	state.GoTransition(APP_REGISTERED, "HALLO")
 	return nil
@@ -54,9 +61,8 @@ func (state *VPNState) Deregister() error {
 	// Close the log file
 	state.CloseLog()
 
-	// Re-initialize everything
-	state = &VPNState{}
-	state.GoTransition(APP_DEREGISTERED, "")
+	state.Server = &Server{}
+	state.InitializeFSM()
 	return nil
 }