fix: will respwan when process is done.

Also added example and readme

example_test.go

@@ -0,0 +1,87 @@
+package supervisor_test
+
+import (
+	"fmt"
+	"path/filepath"
+	"time"
+
+	"github.com/kontera-technologies/go-supervisor/v2"
+)
+
+func Example() {
+	testDir, _ := filepath.Abs("testdata")
+	events := make(chan supervisor.Event)
+	p := supervisor.NewProcess(supervisor.ProcessOptions{
+		Name:                 "./example.sh",
+		Dir:                  testDir,
+		Id:                   "example",
+		EventNotifier:        events,
+		OutputParser:         supervisor.MakeBytesParser,
+		ErrorParser:          supervisor.MakeBytesParser,
+		MaxSpawns:            4,
+		MaxSpawnAttempts:     2,
+		MaxInterruptAttempts: 3,
+		MaxTerminateAttempts: 5,
+		IdleTimeout:          10 * time.Second,
+	})
+
+	exit := make(chan bool)
+
+	go func() {
+		for {
+			select {
+			case msg := <-p.Stdout():
+				fmt.Printf("Recived STDOUT message: %s\n", *msg)
+			case msg := <-p.Stderr():
+				fmt.Printf("Recived STDERR message: %s\n", *msg)
+			case event := <-events:
+				switch event.Code {
+				case "ProcessStart":
+					fmt.Printf("Recived event: %s\n", event.Code)
+				default:
+					fmt.Printf("Recived event: %s - %s\n", event.Code, event.Message)
+				}
+			case <-p.DoneNotifier():
+				fmt.Println("Closing loop we are done...")
+				close(exit)
+				return
+			}
+		}
+	}()
+
+	if err := p.Start(); err != nil {
+		panic(fmt.Sprintf("failed to start process: %s", err))
+	}
+
+	<-exit
+
+	// Output:
+	// Recived event: ProcessStart
+	// Recived STDOUT message: STDOUT MESSAGE
+	// Recived STDERR message: STDERR MESSAGE
+	// Recived event: ProcessDone - exit status 0
+	// Recived event: StoppingHeartbeatMonitoring - Stop signal received.
+	// Recived event: Sleep - Sleeping for 1s before respwaning instance.
+	// Recived event: ProcessRespawn - Trying to respawn instance.
+	// Recived event: ProcessStart
+	// Recived STDOUT message: STDOUT MESSAGE
+	// Recived STDERR message: STDERR MESSAGE
+	// Recived event: ProcessDone - exit status 0
+	// Recived event: StoppingHeartbeatMonitoring - Stop signal received.
+	// Recived event: Sleep - Sleeping for 1s before respwaning instance.
+	// Recived event: ProcessRespawn - Trying to respawn instance.
+	// Recived event: ProcessStart
+	// Recived STDOUT message: STDOUT MESSAGE
+	// Recived STDERR message: STDERR MESSAGE
+	// Recived event: ProcessDone - exit status 0
+	// Recived event: StoppingHeartbeatMonitoring - Stop signal received.
+	// Recived event: Sleep - Sleeping for 1s before respwaning instance.
+	// Recived event: ProcessRespawn - Trying to respawn instance.
+	// Recived event: ProcessStart
+	// Recived STDOUT message: STDOUT MESSAGE
+	// Recived STDERR message: STDERR MESSAGE
+	// Recived event: ProcessDone - exit status 0
+	// Recived event: StoppingHeartbeatMonitoring - Stop signal received.
+	// Recived event: RespawnError - Max number of respawns reached.
+	// Closing loop we are done...
+}