github.com/lalkh/containerd@v1.4.3/cmd/ctr/commands/tasks/attach.go (about)

     1  /*
     2     Copyright The containerd Authors.
     3  
     4     Licensed under the Apache License, Version 2.0 (the "License");
     5     you may not use this file except in compliance with the License.
     6     You may obtain a copy of the License at
     7  
     8         http://www.apache.org/licenses/LICENSE-2.0
     9  
    10     Unless required by applicable law or agreed to in writing, software
    11     distributed under the License is distributed on an "AS IS" BASIS,
    12     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13     See the License for the specific language governing permissions and
    14     limitations under the License.
    15  */
    16  
    17  package tasks
    18  
    19  import (
    20  	"github.com/containerd/console"
    21  	"github.com/containerd/containerd/cio"
    22  	"github.com/containerd/containerd/cmd/ctr/commands"
    23  	"github.com/sirupsen/logrus"
    24  	"github.com/urfave/cli"
    25  )
    26  
    27  var attachCommand = cli.Command{
    28  	Name:      "attach",
    29  	Usage:     "attach to the IO of a running container",
    30  	ArgsUsage: "CONTAINER",
    31  	Action: func(context *cli.Context) error {
    32  		client, ctx, cancel, err := commands.NewClient(context)
    33  		if err != nil {
    34  			return err
    35  		}
    36  		defer cancel()
    37  		container, err := client.LoadContainer(ctx, context.Args().First())
    38  		if err != nil {
    39  			return err
    40  		}
    41  		spec, err := container.Spec(ctx)
    42  		if err != nil {
    43  			return err
    44  		}
    45  		var (
    46  			con console.Console
    47  			tty = spec.Process.Terminal
    48  		)
    49  		if tty {
    50  			con = console.Current()
    51  			defer con.Reset()
    52  			if err := con.SetRaw(); err != nil {
    53  				return err
    54  			}
    55  		}
    56  		task, err := container.Task(ctx, cio.NewAttach(cio.WithStdio))
    57  		if err != nil {
    58  			return err
    59  		}
    60  		defer task.Delete(ctx)
    61  
    62  		statusC, err := task.Wait(ctx)
    63  		if err != nil {
    64  			return err
    65  		}
    66  
    67  		if tty {
    68  			if err := HandleConsoleResize(ctx, task, con); err != nil {
    69  				logrus.WithError(err).Error("console resize")
    70  			}
    71  		} else {
    72  			sigc := commands.ForwardAllSignals(ctx, task)
    73  			defer commands.StopCatch(sigc)
    74  		}
    75  
    76  		ec := <-statusC
    77  		code, _, err := ec.Result()
    78  		if err != nil {
    79  			return err
    80  		}
    81  		if code != 0 {
    82  			return cli.NewExitError("", int(code))
    83  		}
    84  		return nil
    85  	},
    86  }