Fix long output resulting in duplicate lines

Author: boki

cmd/internal/runtest.go

@@ -14,6 +14,7 @@
 package internal
 
 import (
+	"bytes"
 	"context"
 	"encoding/json"
 	"fmt"
@@ -36,6 +37,9 @@ type (
 		printID bool
 		s       *Spinner
 		w       terminalWriter
+
+		mu  sync.Mutex
+		buf bytes.Buffer
 	}
 
 	// RunOutputResult collects the RunOutput and its error, if any, from
@@ -80,17 +84,18 @@ func RunTest(ctx context.Context, target, location string, nodeIDs []int, limit
 		}
 	}()
 
-	f.StartSpinner()
+	if outputJSON {
+		f.StartSpinner()
+	}
 	var o *perfops.RunOutput
 	for {
 		select {
-		case <-time.After(100 * time.Millisecond):
+		case <-time.After(50 * time.Millisecond):
 		}
 		if o, err = res.Output(); err != nil {
 			return err
 		}
 		if !outputJSON && o != nil {
-			f.StopSpinner()
 			PrintOutput(f, o)
 		}
 		if o != nil && o.IsFinished() {
@@ -109,6 +114,20 @@ func PrintOutput(f *Formatter, output *perfops.RunOutput) {
 	if f.printID {
 		f.Printf("Test ID: %v\n", output.ID)
 	}
+	spinner := f.s.Step()
+	if !output.IsFinished() {
+		f.Printf("%s", spinner)
+		if len(output.Items) > 1 {
+			finished := 0
+			for _, item := range output.Items {
+				if item.Result.IsFinished() {
+					finished++
+				}
+			}
+			f.Printf(" %d/%d", finished, len(output.Items))
+		}
+		f.Printf("\n")
+	}
 	for _, item := range output.Items {
 		r := item.Result
 		n := r.Node
@@ -121,12 +140,11 @@ func PrintOutput(f *Formatter, output *perfops.RunOutput) {
 		} else if r.Message != "NO DATA" {
 			f.Printf("Node%d, AS%d, %s, %s\n%s\n", n.ID, n.AsNumber, n.City, n.Country.Name, r.Message)
 		}
+		if !item.Result.IsFinished() {
+			f.Printf("%s\n", spinner)
+		}
 	}
-	spinner := f.s.Step()
-	if !output.IsFinished() {
-		f.Printf("%s\n", spinner)
-	}
-	f.w.Flush()
+	f.Flush(!output.IsFinished())
 }
 
 // PrintOutputJSON marshals the output into JSON and prints the JSON.
@@ -161,7 +179,53 @@ func (f *Formatter) StopSpinner() {
 
 // Printf prints the arguments to the formatters writer.
 func (f *Formatter) Printf(format string, a ...interface{}) (int, error) {
-	return fmt.Fprintf(f.w, format, a...)
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	return fmt.Fprintf(&f.buf, format, a...)
+}
+
+// Flush writes to w and resets the buffer. It should be called after the
+// last call to Printf to ensure that any data buffered in the Writer is
+// written to output.
+// Any incomplete escape sequence at the end is considered complete for
+// formatting purposes.
+// An error is returned if the contents of the buffer cannot be written
+// to the underlying output stream
+func (f *Formatter) Flush(limit bool) error {
+	cols, rows := termSize()
+
+	f.mu.Lock()
+	defer f.mu.Unlock()
+
+	if len(f.buf.Bytes()) == 0 {
+		return nil
+	}
+
+	out := string(f.buf.Bytes())
+	if limit {
+		width := 0
+		lines := 0
+		for i, r := range out {
+			if r == '\n' {
+				width = 0
+				lines++
+			} else if width++; width > cols {
+				width = 0
+				lines++
+			}
+			if lines == rows {
+				out = out[0:i]
+				break
+			}
+		}
+	}
+	termStartOfRow(f.w)
+	_, err := f.w.Write([]byte(out))
+	f.buf.Reset()
+	if err != nil {
+		return err
+	}
+	return f.w.Flush()
 }
 
 // SetOutput sets the output and the error.

cmd/internal/runtest_test.go

@@ -79,18 +79,18 @@ func TestPrintOutput(t *testing.T) {
 		"all": {
 			func() *perfops.RunOutput {
 				var o *perfops.RunOutput
-				json.Unmarshal([]byte(`{"id":"706fc55e3377104da01f05569e35a30b","items":[{"id":"bba072473bd034d432df03730e116686","result":{"output":"121","node":{"id":27,"as_number":12345,"latitude":22.28512548314,"longitude":114.17507171631,"country":{"id":195,"name":"Hong Kong","continent":{"id":2,"name":"Asia","iso":"AS"},"iso":"HK","iso_numeric":"344"},"city":"Hong Kong","sub_region":"Eastern Asia"},"time":1508061924.088372}}],"requested":"sendergram.com","finished":"true","elapsedTime":0.66500000000000004}`), &o)
+				json.Unmarshal([]byte(`{"id":"706fc55e3377104da01f05569e35a30b","items":[{"id":"bba072473bd034d432df03730e116686","result":{"output":"121","finished": true,"node":{"id":27,"as_number":12345,"latitude":22.28512548314,"longitude":114.17507171631,"country":{"id":195,"name":"Hong Kong","continent":{"id":2,"name":"Asia","iso":"AS"},"iso":"HK","iso_numeric":"344"},"city":"Hong Kong","sub_region":"Eastern Asia"},"time":1508061924.088372}}],"requested":"sendergram.com","finished":"true","elapsedTime":0.66500000000000004}`), &o)
 				return o
 			},
-			"Node27, AS12345, Hong Kong, Hong Kong\n121\n",
+			"\x1b[200DNode27, AS12345, Hong Kong, Hong Kong\n121\n",
 		},
 		"timeout": {
 			func() *perfops.RunOutput {
 				var o *perfops.RunOutput
-				json.Unmarshal([]byte(`{"id":"706fc55e3377104da01f05569e35a30b","items":[{"id":"bba072473bd034d432df03730e116686","result":{"output":"-2","node":{"id":27,"as_number":23456,"latitude":22.28512548314,"longitude":114.17507171631,"country":{"id":195,"name":"Hong Kong","continent":{"id":2,"name":"Asia","iso":"AS"},"iso":"HK","iso_numeric":"344"},"city":"Hong Kong","sub_region":"Eastern Asia"},"time":1508061924.088372}}],"requested":"sendergram.com","finished":"true","elapsedTime":0.66500000000000004}`), &o)
+				json.Unmarshal([]byte(`{"id":"706fc55e3377104da01f05569e35a30b","items":[{"id":"bba072473bd034d432df03730e116686","result":{"output":"-2","finished": true,"node":{"id":27,"as_number":23456,"latitude":22.28512548314,"longitude":114.17507171631,"country":{"id":195,"name":"Hong Kong","continent":{"id":2,"name":"Asia","iso":"AS"},"iso":"HK","iso_numeric":"344"},"city":"Hong Kong","sub_region":"Eastern Asia"},"time":1508061924.088372}}],"requested":"sendergram.com","finished":"true","elapsedTime":0.66500000000000004}`), &o)
 				return o
 			},
-			"Node27, AS23456, Hong Kong, Hong Kong\nThe command timed-out. It either took too long to execute or we could not connect to your target at all.\n",
+			"\x1b[200DNode27, AS23456, Hong Kong, Hong Kong\nThe command timed-out. It either took too long to execute or we could not connect to your target at all.\n",
 		},
 	}
 
@@ -115,6 +115,7 @@ type testTerminalWriter struct {
 func (w *testTerminalWriter) Flush() error { return nil }
 
 func newTestFormatter(w io.Writer, printID bool) *Formatter {
+	termCols, termRows = 200, 50
 	f := &Formatter{
 		printID: printID,
 		w:       &testTerminalWriter{w},

cmd/internal/terminal.go

@@ -0,0 +1,34 @@
+// +build !windows
+
+package internal
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"syscall"
+	"unsafe"
+
+	"github.com/gosuri/uilive"
+)
+
+func termSize() (int, int) {
+	if termCols == 0 {
+		if out, err := os.OpenFile("/dev/tty", syscall.O_WRONLY, 0); err == nil {
+			defer out.Close()
+			var size struct {
+				rows    uint16
+				cols    uint16
+				xpixels uint16
+				ypixels uint16
+			}
+			_, _, _ = syscall.Syscall(syscall.SYS_IOCTL, out.Fd(), uintptr(syscall.TIOCGWINSZ), uintptr(unsafe.Pointer(&size)))
+			termCols, termRows = int(size.cols), int(size.rows)
+		}
+	}
+	return termCols, termRows
+}
+
+func termStartOfRow(w io.Writer) {
+	w.Write([]byte(fmt.Sprintf("%c[%dD", uilive.ESC, termCols)))
+}

cmd/internal/terminal_common.go

@@ -0,0 +1,7 @@
+package internal
+
+var (
+	// Cached columns and rows of the terminal window. Initialized by termSize().
+	termCols int
+	termRows int
+)

cmd/internal/terminal_windows.go

@@ -0,0 +1,14 @@
+package internal
+
+import (
+	"io"
+)
+
+func termSize() (int, int) {
+	// TODO: Implement me.
+	return termCols, termRows
+}
+
+func termStartOfRow(w io.Writer) {
+	// TODO: Implement me.
+}