process.go

Documentation: github.com/chaos-mesh/chaos-mesh/pkg/ctrl/server

     1  // Copyright 2021 Chaos Mesh Authors.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  // http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  //
    15  
    16  package server
    17  
    18  import (
    19  	"context"
    20  	"fmt"
    21  	"strings"
    22  
    23  	"github.com/pkg/errors"
    24  	v1 "k8s.io/api/core/v1"
    25  
    26  	"github.com/chaos-mesh/chaos-mesh/pkg/bpm"
    27  	"github.com/chaos-mesh/chaos-mesh/pkg/ctrl/server/model"
    28  )
    29  
    30  // GetPidFromPS returns pid-command pairs
    31  func (r *Resolver) GetPidFromPS(ctx context.Context, pod *v1.Pod) ([]*model.Process, error) {
    32  	cmd := "ps"
    33  	out, err := r.ExecBypass(ctx, pod, cmd, bpm.PidNS, bpm.MountNS)
    34  	if err != nil {
    35  		return nil, errors.Wrapf(err, "run command %s failed", cmd)
    36  	}
    37  	outLines := strings.Split(string(out), "\n")
    38  	if len(outLines) < 2 {
    39  		return nil, errors.New("ps returns empty")
    40  	}
    41  	titles := strings.Fields(outLines[0])
    42  	var pidColumn, cmdColumn int
    43  	for i, t := range titles {
    44  		if t == "PID" {
    45  			pidColumn = i
    46  		}
    47  		if t == "COMMAND" || t == "CMD" {
    48  			cmdColumn = i
    49  		}
    50  	}
    51  	if pidColumn == 0 && cmdColumn == 0 {
    52  		return nil, errors.New("parsing ps error: could not get PID and COMMAND column")
    53  	}
    54  
    55  	var processes []*model.Process
    56  	for _, line := range outLines[1:] {
    57  		item := strings.Fields(line)
    58  		// break when got empty line
    59  		if len(item) == 0 {
    60  			break
    61  		}
    62  		if item[cmdColumn] == cmd {
    63  			continue
    64  		}
    65  		processes = append(processes, &model.Process{
    66  			Pod:     pod,
    67  			Pid:     item[pidColumn],
    68  			Command: item[cmdColumn],
    69  		})
    70  	}
    71  	return processes, nil
    72  }
    73  
    74  // killProcess kill all alive processes in pids
    75  func (r *Resolver) killProcess(ctx context.Context, pod *v1.Pod, pids []string) ([]*model.KillProcessResult, error) {
    76  	pidSet := make(map[string]bool)
    77  	for _, pid := range pids {
    78  		pidSet[pid] = true
    79  	}
    80  
    81  	// all processes in target pod
    82  	allProcess, err := r.GetPidFromPS(ctx, pod)
    83  	if err != nil {
    84  		return nil, errors.Wrapf(err, "get process on pod %s/%s", pod.Namespace, pod.Name)
    85  	}
    86  
    87  	// the intersection of all processes and pids
    88  	var pidList []string
    89  	var killResults []*model.KillProcessResult
    90  
    91  	for _, process := range allProcess {
    92  		if _, ok := pidSet[process.Pid]; ok {
    93  			pidList = append(pidList, process.Pid)
    94  			killResults = append(killResults, &model.KillProcessResult{
    95  				Pid:     process.Pid,
    96  				Command: process.Command,
    97  			})
    98  		}
    99  	}
   100  	if len(pidList) == 0 {
   101  		return nil, nil
   102  	}
   103  	cmd := fmt.Sprintf("kill %s", strings.Join(pids, " "))
   104  	if _, err = r.ExecBypass(ctx, pod, cmd, bpm.PidNS, bpm.MountNS); err != nil {
   105  		return nil, errors.Wrapf(err, "run command %s", cmd)
   106  	}
   107  	return killResults, nil
   108  }
   109