containerd/cmd/ctr/commands/tasks/kill.go
Samuel Karp 607888ce29 ctr: make kill use stop-signal by default
The OCI image specification includes a `StopSignal` field in the image
configuration, denoting the system call signal to be sent to the
container to exit.  This commit adds a new `WithImageStopSignal` container
option that can be used for storing the `StopSignal` field as a label on
the container.  This commit also adjusts `ctr run` to call
`WithImageStopSignal` and `ctr tasks kill` to send the signal stored in
that label by default.

Signed-off-by: Samuel Karp <skarp@amazon.com>
2018-09-27 15:53:38 -07:00

97 lines
2.4 KiB
Go

/*
Copyright The containerd Authors.
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 tasks
import (
"github.com/containerd/containerd"
"github.com/containerd/containerd/cmd/ctr/commands"
"github.com/pkg/errors"
"github.com/urfave/cli"
)
const defaultSignal = "SIGTERM"
var killCommand = cli.Command{
Name: "kill",
Usage: "signal a container (default: SIGTERM)",
ArgsUsage: "[flags] CONTAINER",
Flags: []cli.Flag{
cli.StringFlag{
Name: "signal, s",
Value: "",
Usage: "signal to send to the container",
},
cli.StringFlag{
Name: "exec-id",
Usage: "process ID to kill",
},
cli.BoolFlag{
Name: "all, a",
Usage: "send signal to all processes inside the container",
},
},
Action: func(context *cli.Context) error {
id := context.Args().First()
if id == "" {
return errors.New("container id must be provided")
}
signal, err := containerd.ParseSignal(defaultSignal)
if err != nil {
return err
}
var (
all = context.Bool("all")
execID = context.String("exec-id")
opts []containerd.KillOpts
)
if all && execID != "" {
return errors.New("specify an exec-id or all; not both")
}
client, ctx, cancel, err := commands.NewClient(context)
if err != nil {
return err
}
defer cancel()
if all {
opts = append(opts, containerd.WithKillAll)
}
if execID != "" {
opts = append(opts, containerd.WithKillExecID(execID))
}
container, err := client.LoadContainer(ctx, id)
if err != nil {
return err
}
if context.String("signal") != "" {
signal, err = containerd.ParseSignal(context.String("signal"))
if err != nil {
return err
}
} else {
signal, err = containerd.GetStopSignal(ctx, container, signal)
if err != nil {
return err
}
}
task, err := container.Task(ctx, nil)
if err != nil {
return err
}
return task.Kill(ctx, signal, opts...)
},
}