From 45eaef24319897f5b1679c9d1aa7d88702cce905 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Jano=C5=A1=20Gulja=C5=A1?= Date: Thu, 9 Aug 2018 16:15:59 +0200 Subject: [PATCH] cmd/swarm: solve rare cases of using the same random port in tests (#17352) --- cmd/swarm/config_test.go | 14 ++++ cmd/swarm/run_test.go | 138 +++++++++++++++++++++++++++++++++------ 2 files changed, 132 insertions(+), 20 deletions(-) diff --git a/cmd/swarm/config_test.go b/cmd/swarm/config_test.go index d5011e3a7..02198f878 100644 --- a/cmd/swarm/config_test.go +++ b/cmd/swarm/config_test.go @@ -20,6 +20,7 @@ import ( "fmt" "io" "io/ioutil" + "net" "os" "os/exec" "testing" @@ -559,3 +560,16 @@ func TestValidateConfig(t *testing.T) { } } } + +func assignTCPPort() (string, error) { + l, err := net.Listen("tcp", "127.0.0.1:0") + if err != nil { + return "", err + } + l.Close() + _, port, err := net.SplitHostPort(l.Addr().String()) + if err != nil { + return "", err + } + return port, nil +} diff --git a/cmd/swarm/run_test.go b/cmd/swarm/run_test.go index a70c4686d..90d3c98ba 100644 --- a/cmd/swarm/run_test.go +++ b/cmd/swarm/run_test.go @@ -17,12 +17,15 @@ package main import ( + "context" "fmt" "io/ioutil" "net" "os" "path/filepath" "runtime" + "sync" + "syscall" "testing" "time" @@ -218,14 +221,12 @@ func existingTestNode(t *testing.T, dir string, bzzaccount string) *testNode { } // assign ports - httpPort, err := assignTCPPort() - if err != nil { - t.Fatal(err) - } - p2pPort, err := assignTCPPort() + ports, err := getAvailableTCPPorts(2) if err != nil { t.Fatal(err) } + p2pPort := ports[0] + httpPort := ports[1] // start the node node.Cmd = runSwarm(t, @@ -246,6 +247,17 @@ func existingTestNode(t *testing.T, dir string, bzzaccount string) *testNode { } }() + ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second) + defer cancel() + + // ensure that all ports have active listeners + // so that the next node will not get the same + // when calling getAvailableTCPPorts + err = waitTCPPorts(ctx, ports...) + if err != nil { + t.Fatal(err) + } + // wait for the node to start for start := time.Now(); time.Since(start) < 10*time.Second; time.Sleep(50 * time.Millisecond) { node.Client, err = rpc.Dial(conf.IPCEndpoint()) @@ -280,14 +292,12 @@ func newTestNode(t *testing.T, dir string) *testNode { node := &testNode{Dir: dir} // assign ports - httpPort, err := assignTCPPort() - if err != nil { - t.Fatal(err) - } - p2pPort, err := assignTCPPort() + ports, err := getAvailableTCPPorts(2) if err != nil { t.Fatal(err) } + p2pPort := ports[0] + httpPort := ports[1] // start the node node.Cmd = runSwarm(t, @@ -308,6 +318,17 @@ func newTestNode(t *testing.T, dir string) *testNode { } }() + ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second) + defer cancel() + + // ensure that all ports have active listeners + // so that the next node will not get the same + // when calling getAvailableTCPPorts + err = waitTCPPorts(ctx, ports...) + if err != nil { + t.Fatal(err) + } + // wait for the node to start for start := time.Now(); time.Since(start) < 10*time.Second; time.Sleep(50 * time.Millisecond) { node.Client, err = rpc.Dial(conf.IPCEndpoint()) @@ -343,15 +364,92 @@ func (n *testNode) Shutdown() { } } -func assignTCPPort() (string, error) { - l, err := net.Listen("tcp", "127.0.0.1:0") - if err != nil { - return "", err +// getAvailableTCPPorts returns a set of ports that +// nothing is listening on at the time. +// +// Function assignTCPPort cannot be called in sequence +// and guardantee that the same port will be returned in +// different calls as the listener is closed within the function, +// not after all listeners are started and selected unique +// available ports. +func getAvailableTCPPorts(count int) (ports []string, err error) { + for i := 0; i < count; i++ { + l, err := net.Listen("tcp", "127.0.0.1:0") + if err != nil { + return nil, err + } + // defer close in the loop to be sure the same port will not + // be selected in the next iteration + defer l.Close() + + _, port, err := net.SplitHostPort(l.Addr().String()) + if err != nil { + return nil, err + } + ports = append(ports, port) + } + return ports, nil +} + +// waitTCPPorts blocks until tcp connections can be +// established on all provided ports. It runs all +// ports dialers in parallel, and returns the first +// encountered error. +// See waitTCPPort also. +func waitTCPPorts(ctx context.Context, ports ...string) error { + var err error + // mu locks err variable that is assigned in + // other goroutines + var mu sync.Mutex + + // cancel is canceling all goroutines + // when the firs error is returned + // to prevent unnecessary waiting + ctx, cancel := context.WithCancel(ctx) + defer cancel() + + var wg sync.WaitGroup + for _, port := range ports { + wg.Add(1) + go func(port string) { + defer wg.Done() + + e := waitTCPPort(ctx, port) + + mu.Lock() + defer mu.Unlock() + if e != nil && err == nil { + err = e + cancel() + } + }(port) + } + wg.Wait() + + return err +} + +// waitTCPPort blocks until tcp connection can be established +// ona provided port. It has a 3 minute timeout as maximum, +// to prevent long waiting, but it can be shortened with +// a provided context instance. Dialer has a 10 second timeout +// in every iteration, and connection refused error will be +// retried in 100 milliseconds periods. +func waitTCPPort(ctx context.Context, port string) error { + ctx, cancel := context.WithTimeout(ctx, 3*time.Minute) + defer cancel() + + for { + c, err := (&net.Dialer{Timeout: 10 * time.Second}).DialContext(ctx, "tcp", "127.0.0.1:"+port) + if err != nil { + if operr, ok := err.(*net.OpError); ok { + if syserr, ok := operr.Err.(*os.SyscallError); ok && syserr.Err == syscall.ECONNREFUSED { + time.Sleep(100 * time.Millisecond) + continue + } + } + return err + } + return c.Close() } - l.Close() - _, port, err := net.SplitHostPort(l.Addr().String()) - if err != nil { - return "", err - } - return port, nil }