ceph-csi/vendor/k8s.io/kubernetes/pkg/kubectl/plugins/runner.go

75 lines
1.9 KiB
Go
Raw Normal View History

2018-01-09 18:57:14 +00:00
/*
Copyright 2017 The Kubernetes 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 plugins
import (
"io"
"os"
"os/exec"
"strings"
"github.com/golang/glog"
)
// PluginRunner is capable of running a plugin in a given running context.
type PluginRunner interface {
Run(plugin *Plugin, ctx RunningContext) error
}
// RunningContext holds the context in which a given plugin is running - the
// in, out, and err streams, arguments and environment passed to it, and the
// working directory.
type RunningContext struct {
In io.Reader
Out io.Writer
ErrOut io.Writer
Args []string
EnvProvider EnvProvider
WorkingDir string
}
// ExecPluginRunner is a PluginRunner that uses Go's os/exec to run plugins.
type ExecPluginRunner struct{}
// Run takes a given plugin and runs it in a given context using os/exec, returning
// any error found while running.
func (r *ExecPluginRunner) Run(plugin *Plugin, ctx RunningContext) error {
command := strings.Split(os.ExpandEnv(plugin.Command), " ")
base := command[0]
args := []string{}
if len(command) > 1 {
args = command[1:]
}
args = append(args, ctx.Args...)
cmd := exec.Command(base, args...)
cmd.Stdin = ctx.In
cmd.Stdout = ctx.Out
cmd.Stderr = ctx.ErrOut
env, err := ctx.EnvProvider.Env()
if err != nil {
return err
}
cmd.Env = env.Slice()
cmd.Dir = ctx.WorkingDir
glog.V(9).Infof("Running plugin %q as base command %q with args %v", plugin.Name, base, args)
return cmd.Run()
}