cri-o/server/container_attach.go
Antonio Murdaca b959f8996d
server: add prometheus metrics for CRI operations
Signed-off-by: Antonio Murdaca <runcom@redhat.com>
2017-11-09 16:51:00 +01:00

153 lines
3.7 KiB
Go

package server
import (
"fmt"
"io"
"net"
"os"
"path/filepath"
"time"
"github.com/kubernetes-incubator/cri-o/oci"
"github.com/kubernetes-incubator/cri-o/utils"
"github.com/sirupsen/logrus"
"golang.org/x/net/context"
"golang.org/x/sys/unix"
"k8s.io/client-go/tools/remotecommand"
pb "k8s.io/kubernetes/pkg/kubelet/apis/cri/v1alpha1/runtime"
kubecontainer "k8s.io/kubernetes/pkg/kubelet/container"
)
/* Sync with stdpipe_t in conmon.c */
const (
AttachPipeStdin = 1
AttachPipeStdout = 2
AttachPipeStderr = 3
)
// Attach prepares a streaming endpoint to attach to a running container.
func (s *Server) Attach(ctx context.Context, req *pb.AttachRequest) (resp *pb.AttachResponse, err error) {
const operation = "attach"
defer func() {
recordOperation(operation, time.Now())
recordError(operation, err)
}()
logrus.Debugf("AttachRequest %+v", req)
resp, err = s.GetAttach(req)
if err != nil {
return nil, fmt.Errorf("unable to prepare attach endpoint")
}
return resp, nil
}
// Attach endpoint for streaming.Runtime
func (ss streamService) Attach(containerID string, inputStream io.Reader, outputStream, errorStream io.WriteCloser, tty bool, resize <-chan remotecommand.TerminalSize) error {
c := ss.runtimeServer.GetContainer(containerID)
if c == nil {
return fmt.Errorf("could not find container %q", containerID)
}
if err := ss.runtimeServer.Runtime().UpdateStatus(c); err != nil {
return err
}
cState := ss.runtimeServer.Runtime().ContainerStatus(c)
if !(cState.Status == oci.ContainerStateRunning || cState.Status == oci.ContainerStateCreated) {
return fmt.Errorf("container is not created or running")
}
controlPath := filepath.Join(c.BundlePath(), "ctl")
controlFile, err := os.OpenFile(controlPath, unix.O_WRONLY, 0)
if err != nil {
return fmt.Errorf("failed to open container ctl file: %v", err)
}
kubecontainer.HandleResizing(resize, func(size remotecommand.TerminalSize) {
logrus.Infof("Got a resize event: %+v", size)
_, err := fmt.Fprintf(controlFile, "%d %d %d\n", 1, size.Height, size.Width)
if err != nil {
logrus.Infof("Failed to write to control file to resize terminal: %v", err)
}
})
attachSocketPath := filepath.Join(oci.ContainerAttachSocketDir, c.ID(), "attach")
conn, err := net.DialUnix("unixpacket", nil, &net.UnixAddr{Name: attachSocketPath, Net: "unixpacket"})
if err != nil {
return fmt.Errorf("failed to connect to container %s attach socket: %v", c.ID(), err)
}
defer conn.Close()
receiveStdout := make(chan error)
if outputStream != nil || errorStream != nil {
go func() {
receiveStdout <- redirectResponseToOutputStreams(outputStream, errorStream, conn)
}()
}
stdinDone := make(chan error)
go func() {
var err error
if inputStream != nil {
_, err = utils.CopyDetachable(conn, inputStream, nil)
conn.CloseWrite()
}
stdinDone <- err
}()
select {
case err := <-receiveStdout:
return err
case err := <-stdinDone:
if _, ok := err.(utils.DetachError); ok {
return nil
}
if outputStream != nil || errorStream != nil {
return <-receiveStdout
}
}
return nil
}
func redirectResponseToOutputStreams(outputStream, errorStream io.Writer, conn io.Reader) error {
var err error
buf := make([]byte, 8192+1) /* Sync with conmon STDIO_BUF_SIZE */
for {
nr, er := conn.Read(buf)
if nr > 0 {
var dst io.Writer
if buf[0] == AttachPipeStdout {
dst = outputStream
} else if buf[0] == AttachPipeStderr {
dst = errorStream
} else {
logrus.Infof("Got unexpected attach type %+d", buf[0])
}
if dst != nil {
nw, ew := dst.Write(buf[1:nr])
if ew != nil {
err = ew
break
}
if nr != nw+1 {
err = io.ErrShortWrite
break
}
}
}
if er == io.EOF {
break
}
if er != nil {
err = er
break
}
}
return err
}