[skip ci] live streaming VCH creation log to VCH datastore folder

cmd/vic-machine/main.go

@@ -32,6 +32,7 @@ import (
 	"github.com/vmware/vic/cmd/vic-machine/list"
 	"github.com/vmware/vic/cmd/vic-machine/update"
 	"github.com/vmware/vic/cmd/vic-machine/upgrade"
+	"github.com/vmware/vic/lib/install/vchlog"
 	viclog "github.com/vmware/vic/pkg/log"
 	"github.com/vmware/vic/pkg/version"
 )
@@ -139,6 +140,12 @@ func main() {
 		logs = append(logs, f)
 	}
 
+	// create the logger for streaming VCH log messages
+	vchlog.Init()
+	logs = append(logs, vchlog.GetPipe())
+	go vchlog.Run()
+	defer vchlog.Close() // close the logger pipe when done
+
 	// Initiliaze logger with default TextFormatter
 	log.SetFormatter(viclog.NewTextFormatter())
 	// SetOutput to io.MultiWriter so that we can log to stdout and a file

lib/install/management/create.go

@@ -26,6 +26,7 @@ import (
 	"github.com/vmware/govmomi/object"
 	"github.com/vmware/vic/lib/config"
 	"github.com/vmware/vic/lib/install/data"
+	"github.com/vmware/vic/lib/install/vchlog"
 	"github.com/vmware/vic/pkg/errors"
 	"github.com/vmware/vic/pkg/retry"
 	"github.com/vmware/vic/pkg/trace"
@@ -37,6 +38,7 @@ const (
 	uploadMaxElapsedTime  = 30 * time.Minute
 	uploadMaxInterval     = 1 * time.Minute
 	uploadInitialInterval = 10 * time.Second
+	timeFormat            = "2006-01-02T15:04:05-0700"
 )
 
 func (d *Dispatcher) CreateVCH(conf *config.VirtualContainerHostConfigSpec, settings *data.InstallerData) error {
@@ -60,6 +62,16 @@ func (d *Dispatcher) CreateVCH(conf *config.VirtualContainerHostConfigSpec, sett
 		return errors.Errorf("Creating the appliance failed with %s. Exiting...", err)
 	}
 
+	// send the signal to VCH logger to indicate VCH datastore path is ready
+	datastoreReadySignal := vchlog.DatastoreReadySignal{
+		Datastore:   d.session.Datastore,
+		LogFileName: "vic-machine-create",
+		Operation:   trace.NewOperation(d.ctx, "vic-machine create"),
+		VMPathName:  d.vmPathName,
+		Timestamp:   time.Now().UTC().Format(timeFormat),
+	}
+	vchlog.Signal(datastoreReadySignal)
+
 	if err = d.uploadImages(settings.ImageFiles); err != nil {
 		return errors.Errorf("Uploading images failed with %s. Exiting...", err)
 	}
@@ -139,7 +151,7 @@ func (d *Dispatcher) uploadImages(files map[string]string) error {
 					switch err.(type) {
 					// if not found, do nothing
 					case object.DatastoreNoSuchFileError:
-					// otherwise force delete
+						// otherwise force delete
 					default:
 						log.Debugf("target delete path = %s", isoTargetPath)
 						err := fm.Delete(d.ctx, isoTargetPath)

lib/install/vchlog/bufferedPipe.go

@@ -0,0 +1,82 @@
+// Copyright 2016-2017 VMware, Inc. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package vchlog
+
+import (
+	"bytes"
+	"sync"
+	"io"
+)
+
+// BufferedPipe struct implements a pipe readwriter with buffer
+// buffer: the internal buffer to hold data
+// c: the sync locker to manage concurrent reads and writes
+// closed: boolean indicating if the stream is closed
+type BufferedPipe struct {
+	buffer *bytes.Buffer
+	c      *sync.Cond
+	closed bool
+}
+
+// NewBufferedPipe returns a new buffered pipe instance
+// the internal buffer is initialized to default size.
+// Since internal memory is used, need to make sure that buffered data is bounded.
+func NewBufferedPipe() *BufferedPipe {
+	var m sync.Mutex
+	c := sync.NewCond(&m)
+	return &BufferedPipe{
+		buffer: bytes.NewBuffer(nil),
+		c:      c,
+		closed: false,
+	}
+}
+
+// Read is blocked until a writer in the queue is done writing (until data is available)
+func (bp *BufferedPipe) Read(data []byte) (n int, err error) {
+	bp.c.L.Lock()
+	defer bp.c.L.Unlock()
+
+	// pipe closed, drop all left-over data
+	if bp.closed {
+		return 0, io.EOF
+	}
+	for bp.buffer.Len() == 0 && !bp.closed {
+		bp.c.Wait()
+	}
+
+	return bp.buffer.Read(data)
+}
+
+// Write writes to the internal buffer, and signals one of the reader in queue to start reading.
+func (bp *BufferedPipe) Write(data []byte) (n int, err error) {
+	bp.c.L.Lock()
+	defer bp.c.L.Unlock()
+	defer bp.c.Signal()
+
+	if bp.closed {
+		return 0, io.ErrUnexpectedEOF
+	}
+
+	return bp.buffer.Write(data)
+}
+
+// Close closes the pipe.
+func (bp *BufferedPipe) Close() (err error) {
+	bp.c.L.Lock()
+	defer bp.c.L.Unlock()
+	defer bp.c.Signal()
+	bp.closed = true
+	return nil
+}

lib/install/vchlog/bufferedPipe_test.go

@@ -0,0 +1,230 @@
+// Copyright 2016-2017 VMware, Inc. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package vchlog
+
+import (
+	. "io"
+	"strconv"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+)
+
+// Part 1. Test basic pipe functionality
+// (Referred to: https://golang.org/src/io/pipe_test.go)
+
+// Test a single read and write
+func TestSingleReadWrite(t *testing.T) {
+	testByte := []byte("hello world")
+	toRead := make([]byte, 64)
+	bp := NewBufferedPipe()
+	writeDone := make(chan int)
+
+	// write to the pipe
+	go write(t, bp, testByte, len(testByte), writeDone)
+
+	// read from the pipe
+	read(t, bp, toRead, len(testByte), nil)
+	assert.Equal(t, string(testByte), string(toRead[0:len(testByte)]),
+		"expected %s, read %s", string(testByte), string(toRead[0:len(testByte)]))
+
+	<-writeDone
+	bp.Close()
+}
+
+// Test a sequence of reads and writes
+func readSequence(t *testing.T, r Reader, c chan int) {
+	buf := make([]byte, 64)
+	for {
+		n, err := r.Read(buf)
+		if err == EOF {
+			c <- 0
+			break
+		}
+		assert.Nil(t, err, "read error: %v", err)
+		c <- n
+	}
+}
+
+func TestSequenceReadsWrites(t *testing.T) {
+	readDone := make(chan int)
+	bp := NewBufferedPipe()
+	buf := make([]byte, 64)
+
+	// fire the reader
+	go readSequence(t, bp, readDone)
+
+	// write to the pipe
+	for i := 0; i < 5; i++ {
+		l := 5 + i*10
+		toWrite := buf[0:l]
+		write(t, bp, toWrite, l, nil)
+
+		n := <-readDone
+		assert.Equal(t, l, n, "wrote %d bytes, read %d bytes", l, n)
+	}
+
+	bp.Close()
+	n := <-readDone
+	assert.Equal(t, 0, n, "final read should be 0, got %d", n)
+}
+
+// Part 2. Test buffered pipe functionalities
+
+// Test write buffering
+func TestWriteBuffering(t *testing.T) {
+	bp := NewBufferedPipe()
+
+	// write first chunk of data
+	firstChunk := make([]byte, 16)
+	write(t, bp, firstChunk, len(firstChunk), nil)
+
+	// fire the reader
+	readDone := make(chan int)
+	go func() {
+		buf := make([]byte, 64)
+		for i := 0; i < 2; i++ {
+			l := 8 * (i + 2)
+			read(t, bp, buf, l, nil)
+		}
+		readDone <- 0
+	}()
+
+	// sleep before the next write
+	time.Sleep(time.Second * 5)
+
+	// write second chunk of data
+	secondChunk := make([]byte, 24)
+	write(t, bp, secondChunk, len(secondChunk), nil)
+
+	<-readDone
+	bp.Close()
+}
+
+// Test concurrent writers
+func writeSequence(t *testing.T, w Writer, l int, c chan int) {
+	for i := 0; i < l; i++ {
+		write(t, w, []byte(strconv.Itoa(i)), 1, nil)
+	}
+	time.Sleep(1 * time.Second)
+	c <- 0
+}
+
+func TestConcurrentWriter(t *testing.T) {
+	bp := NewBufferedPipe()
+	l := 10
+	writersNum := 5
+	total := writersNum * l
+
+	// fire 5 concurrent writers
+	chans := make([]chan int, writersNum)
+	for i := 0; i < writersNum; i++ {
+		chans[i] = make(chan int)
+		go writeSequence(t, bp, l, chans[i])
+	}
+
+	// fire one concurrent reader
+	finalLen := 0
+	readDone := make(chan int)
+	go func() {
+		for {
+			buf := make([]byte, 16)
+			n, err := bp.Read(buf)
+			if err == EOF {
+				break
+			}
+			assert.Nil(t, err, "read error: %v", err)
+			finalLen += n
+		}
+		readDone <- 0
+	}()
+
+	// wait for writers to finish
+	for i := 0; i < writersNum; i++ {
+		<-chans[i]
+	}
+	bp.Close()
+
+	// check if the output has all the bytes
+	<-readDone
+	assert.Equal(t, total, finalLen,
+		"%d concurrent writers wrote %d bytes total, got %d bytes", writersNum, total, finalLen)
+}
+
+// Part 3. Edge cases
+
+// Test read on closed pipe during read
+func delayClose(t *testing.T, cl Closer, c chan int) {
+	time.Sleep(1 * time.Millisecond)
+	err := cl.Close()
+	assert.Nil(t, err, "close error: %v", err)
+	c <- 0
+}
+
+func TestPipeReadClose(t *testing.T) {
+	bp := NewBufferedPipe()
+	c := make(chan int)
+
+	// delay closer
+	go delayClose(t, bp, c)
+
+	// read is expected to block until the pipe is closed
+	buf := make([]byte, 64)
+	n, err := bp.Read(buf)
+	<-c
+
+	assert.Equal(t, EOF, err, "read from closed pipe: %v want %v", err, EOF)
+	assert.Equal(t, 0, n, "read on closed pipe returned %d bytes", n)
+}
+
+// Test write on closed pipe during write
+func TestPipeWriteClose(t *testing.T) {
+	bp := NewBufferedPipe()
+
+	// close pipe
+	bp.Close()
+
+	// write
+	buf := make([]byte, 64)
+	n, err := bp.Write(buf)
+
+	assert.Equal(t, ErrUnexpectedEOF, err, "write to closed pipe: %v want %v", err, ErrUnexpectedEOF)
+	assert.Equal(t, 0, n, "write on closed pipe returned %d bytes", n)
+}
+
+// Helper Functions
+
+// write writes the data and report any error
+func write(t *testing.T, w Writer, data []byte, expected int, c chan int) {
+	n, err := w.Write(data)
+	assert.Nil(t, err, "write error: %v", err)
+	assert.Equal(t, expected, n, "expected %d bytes, wrote %d", expected, n)
+
+	if c != nil {
+		c <- 0
+	}
+}
+
+// read reads to buffer and report any error
+func read(t *testing.T, r Reader, buf []byte, expected int, c chan int) {
+	n, err := r.Read(buf)
+	assert.Nil(t, err, "read error: %v", err)
+	assert.Equal(t, expected, n, "expected %d bytes, read %d", expected, n)
+
+	if c != nil {
+		c <- 0
+	}
+}