add functions/vendor files

vendor/github.com/ccirello/supervisor/doc.go

@@ -0,0 +1,78 @@
+/*
+Package supervisor provides supervisor trees for Go applications.
+
+This package implements supervisor trees, similar to what Erlang runtime offers.
+It is built on top of context package, with all of its advantages, namely the
+possibility trickle down context-related values and cancelation signals.
+
+A supervisor tree can be composed either of services or other supervisors - each
+supervisor can have its own set of configurations. Any instance of
+supervisor.Service can be added to a tree.
+
+	Supervisor
+	     ├─▶ Supervisor (if one service dies, only one is restarted)
+	     │       ├─▶ Service
+	     │       └─▶ Service
+	     ├─▶ Group (if one service dies, all others are restarted too)
+	     │       └─▶ Service
+	     │           Service
+	     │           Service
+	     └─▶ Service
+
+Example:
+	package main
+
+	import (
+		"fmt"
+		"os"
+		"os/signal"
+		"time"
+
+		"cirello.io/supervisor"
+		"context"
+	)
+
+	type Simpleservice int
+
+	func (s *Simpleservice) String() string {
+		return fmt.Sprintf("simple service %d", int(*s))
+	}
+
+	func (s *Simpleservice) Serve(ctx context.Context) {
+		for {
+			select {
+			case <-ctx.Done():
+				return
+			default:
+				fmt.Println("do something...")
+				time.Sleep(500 * time.Millisecond)
+			}
+		}
+	}
+
+	func main(){
+		svc := Simpleservice(1)
+		supervisor.Add(&svc)
+
+		// Simply, if not special context is needed:
+		// supervisor.Serve()
+		// Or, using context.Context to propagate behavior:
+		c := make(chan os.Signal, 1)
+		signal.Notify(c, os.Interrupt)
+		ctx, cancel := context.WithCancel(context.Background())
+		go func(){
+			<-c
+			fmt.Println("halting supervisor...")
+			cancel()
+		}()
+		supervisor.ServeContext(ctx)
+	}
+
+TheJerf's blog post about Suture is a very good and helpful read to understand
+how this package has been implemented.
+
+This is package is inspired by github.com/thejerf/suture
+
+http://www.jerf.org/iri/post/2930
+*/
+package supervisor // import "cirello.io/supervisor"