diff --git a/p2p/simulations/adapters/exec.go b/p2p/simulations/adapters/exec.go index a566fb27d8f1..f381c11596d2 100644 --- a/p2p/simulations/adapters/exec.go +++ b/p2p/simulations/adapters/exec.go @@ -17,7 +17,6 @@ package adapters import ( - "bufio" "context" "crypto/ecdsa" "encoding/json" @@ -29,7 +28,6 @@ import ( "os/exec" "os/signal" "path/filepath" - "regexp" "strings" "sync" "syscall" @@ -150,10 +148,6 @@ func (n *ExecNode) Client() (*rpc.Client, error) { return n.client, nil } -// wsAddrPattern is a regex used to read the WebSocket address from the node's -// log -var wsAddrPattern = regexp.MustCompile(`ws://[\d.:]+`) - // Start exec's the node passing the ID and service as command line arguments // and the node config encoded as JSON in the _P2P_NODE_CONFIG environment // variable @@ -196,23 +190,9 @@ func (n *ExecNode) Start(snapshots map[string][]byte) (err error) { n.Cmd = cmd // read the WebSocket address from the stderr logs - var wsAddr string - wsAddrC := make(chan string) - go func() { - s := bufio.NewScanner(stderrR) - for s.Scan() { - if strings.Contains(s.Text(), "WebSocket endpoint opened:") { - wsAddrC <- wsAddrPattern.FindString(s.Text()) - } - } - }() - select { - case wsAddr = <-wsAddrC: - if wsAddr == "" { - return errors.New("failed to read WebSocket address from stderr") - } - case <-time.After(10 * time.Second): - return errors.New("timed out waiting for WebSocket address on stderr") + wsAddr, err := findWSAddr(stderrR, 10*time.Second) + if err != nil { + return fmt.Errorf("error getting WebSocket address: %s", err) } // create the RPC client and load the node info diff --git a/p2p/simulations/adapters/ws.go b/p2p/simulations/adapters/ws.go new file mode 100644 index 000000000000..979a21709e49 --- /dev/null +++ b/p2p/simulations/adapters/ws.go @@ -0,0 +1,51 @@ +package adapters + +import ( + "bufio" + "errors" + "io" + "regexp" + "strings" + "time" +) + +// wsAddrPattern is a regex used to read the WebSocket address from the node's +// log +var wsAddrPattern = regexp.MustCompile(`ws://[\d.:]+`) + +func matchWSAddr(str string) (string, bool) { + if !strings.Contains(str, "WebSocket endpoint opened") { + return "", false + } + + return wsAddrPattern.FindString(str), true +} + +// findWSAddr scans through reader r, looking for the log entry with +// WebSocket address information. +func findWSAddr(r io.Reader, timeout time.Duration) (string, error) { + ch := make(chan string) + + go func() { + s := bufio.NewScanner(r) + for s.Scan() { + addr, ok := matchWSAddr(s.Text()) + if ok { + ch <- addr + } + } + close(ch) + }() + + var wsAddr string + select { + case wsAddr = <-ch: + if wsAddr == "" { + return "", errors.New("empty result") + } + case <-time.After(timeout): + return "", errors.New("timed out") + } + + return wsAddr, nil +} diff --git a/p2p/simulations/adapters/ws_test.go b/p2p/simulations/adapters/ws_test.go new file mode 100644 index 000000000000..0bb9ed2b2b0d --- /dev/null +++ b/p2p/simulations/adapters/ws_test.go @@ -0,0 +1,21 @@ +package adapters + +import ( + "bytes" + "testing" + "time" +) + +func TestFindWSAddr(t *testing.T) { + line := `t=2018-05-02T19:00:45+0200 lvl=info msg="WebSocket endpoint opened" node.id=26c65a606d1125a44695bc08573190d047152b6b9a776ccbbe593e90f91444d9c1ebdadac6a775ad9fdd0923468a1d698ed3a842c1fb89c1bc0f9d4801f8c39c url=ws://127.0.0.1:59975` + buf := bytes.NewBufferString(line) + got, err := findWSAddr(buf, 10*time.Second) + if err != nil { + t.Fatalf("Failed to find addr: %v", err) + } + expected := `ws://127.0.0.1:59975` + + if got != expected { + t.Fatalf("Expected to get '%s', but got '%s'", expected, got) + } +}