Split client app into cmd and daemon service (#239)

client/internal/state.go

@@ -0,0 +1,67 @@
+package internal
+
+import (
+	"context"
+	"sync"
+)
+
+type StatusType string
+
+const (
+	StatusIdle StatusType = "Idle"
+
+	StatusConnecting StatusType = "Connecting"
+	StatusConnected  StatusType = "Connected"
+)
+
+// CtxInitState setup context state into the context tree.
+//
+// This function should be used to initialize context before
+// CtxGetState will be executed.
+func CtxInitState(ctx context.Context) context.Context {
+	return context.WithValue(ctx, stateCtx, &contextState{
+		status: StatusIdle,
+	})
+}
+
+// CtxGetState object to get/update state/errors of process.
+func CtxGetState(ctx context.Context) *contextState {
+	return ctx.Value(stateCtx).(*contextState)
+}
+
+type contextState struct {
+	err    error
+	status StatusType
+	mutex  sync.Mutex
+}
+
+func (c *contextState) Set(update StatusType) {
+	c.mutex.Lock()
+	defer c.mutex.Unlock()
+
+	c.status = update
+	c.err = nil
+}
+
+func (c *contextState) Status() (StatusType, error) {
+	c.mutex.Lock()
+	defer c.mutex.Unlock()
+
+	if c.err != nil {
+		return "", c.err
+	}
+
+	return c.status, nil
+}
+
+func (c *contextState) Wrap(err error) error {
+	c.mutex.Lock()
+	defer c.mutex.Unlock()
+
+	c.err = err
+	return err
+}
+
+type stateKey int
+
+var stateCtx stateKey