add tests for ListenRangeConfig.Listen

common/net/configure_port_test.go

@@ -0,0 +1,155 @@
+package net
+
+import (
+	"context"
+	"net"
+	"testing"
+	"time"
+)
+
+func TestListenRangeConfig_Listen(t *testing.T) {
+
+	topCtx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	var err error
+	var lockedListener *Listener
+	{ // open a random port in range
+		ctx, cancel := context.WithTimeout(topCtx, time.Second*5)
+
+		lockedListener, err = ListenRangeConfig{
+			Min:  800,
+			Max:  10000,
+			Addr: "localhost",
+		}.Listen(ctx)
+		if err != nil {
+			t.Fatalf("could not open first port")
+		}
+		cancel()
+		defer lockedListener.Close() // in case
+	}
+
+	{ // open a second random port in range
+		ctx, cancel := context.WithTimeout(topCtx, time.Second*5)
+
+		listener, err := ListenRangeConfig{
+			Min:  800,
+			Max:  10000,
+			Addr: "localhost",
+		}.Listen(ctx)
+		if err != nil {
+			t.Fatalf("could not open first port")
+		}
+		cancel()
+		if err := listener.Close(); err != nil { // in case
+			t.Fatal("failed to close second random port")
+		}
+	}
+
+	{ // test that opened port cannot be openned using min/max
+		ctx, cancel := context.WithTimeout(topCtx, 250*time.Millisecond)
+
+		l, err := ListenRangeConfig{
+			Min: lockedListener.Port,
+			Max: lockedListener.Port,
+		}.Listen(ctx)
+		if err != context.DeadlineExceeded {
+			l.Close()
+			t.Fatalf("port should be taken, this should timeout: %v", err)
+		}
+		cancel()
+	}
+
+	{ // test that opened port cannot be openned using min only
+		ctx, cancel := context.WithTimeout(topCtx, 250*time.Millisecond)
+
+		l, err := ListenRangeConfig{
+			Min: lockedListener.Port,
+		}.Listen(ctx)
+		if err != context.DeadlineExceeded {
+			l.Close()
+			t.Fatalf("port should be taken, this should timeout: %v", err)
+		}
+		cancel()
+	}
+
+	err = lockedListener.Close() // close port and release lock file
+	if err != nil {
+		t.Fatalf("could not release lockfile or port: %v", err)
+	}
+
+	{ // test that closed port can be reopenned.
+		ctx, cancel := context.WithTimeout(topCtx, 250*time.Millisecond)
+
+		lockedListener, err = ListenRangeConfig{
+			Min: lockedListener.Port,
+		}.Listen(ctx)
+		if err != nil {
+			t.Fatalf("port should have been freed: %v", err)
+		}
+		cancel()
+		defer lockedListener.Close() // in case
+	}
+
+	err = lockedListener.Listener.Close() // close listener, keep lockfile only
+	if err != nil {
+		t.Fatalf("could not release lockfile or port: %v", err)
+	}
+
+	{ // test that file locked port cannot be opened
+		ctx, cancel := context.WithTimeout(topCtx, 250*time.Millisecond)
+
+		l, err := ListenRangeConfig{
+			Min: lockedListener.Port,
+		}.Listen(ctx)
+		if err != context.DeadlineExceeded {
+			l.Close()
+			t.Fatalf("port should be file locked, this should timeout: %v", err)
+		}
+		cancel()
+	}
+
+	var netListener net.Listener
+	{ // test that network port was closed. using net.Listen
+		netListener, err = net.Listen("tcp", lockedListener.Addr().String())
+		if err != nil {
+			t.Fatalf("listen on freed port failed: %v", err)
+		}
+
+	}
+
+	if err := lockedListener.lock.Unlock(); err != nil {
+		t.Fatalf("error closing port: %v", err)
+	}
+
+	{ // test that busy port cannot be opened
+		ctx, cancel := context.WithTimeout(topCtx, 250*time.Millisecond)
+
+		l, err := ListenRangeConfig{
+			Min: lockedListener.Port,
+		}.Listen(ctx)
+		if err != context.DeadlineExceeded {
+			l.Close()
+			t.Fatalf("port should be file locked, this should timeout: %v", err)
+		}
+		cancel()
+	}
+
+	if err := netListener.Close(); err != nil { // free port
+		t.Fatalf("close failed: %v", err)
+	}
+
+	{ // test that freed port can be opened
+		ctx, cancel := context.WithTimeout(topCtx, 250*time.Minute)
+
+		lockedListener, err = ListenRangeConfig{
+			Min: lockedListener.Port,
+		}.Listen(ctx)
+		if err != nil {
+			t.Fatalf("port should have been freed: %v", err)
+		}
+		cancel()
+		defer lockedListener.Close() // in case
+	}
+
+}