client.go

Documentation: github.com/chaos-mesh/chaos-mesh/pkg/chaosdaemon/crclients/crio

     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 crio
    17  
    18  import (
    19  	"context"
    20  	"encoding/json"
    21  	"fmt"
    22  	"net"
    23  	"net/http"
    24  	"syscall"
    25  	"time"
    26  
    27  	"github.com/pkg/errors"
    28  	"google.golang.org/grpc"
    29  	v1 "k8s.io/cri-api/pkg/apis/runtime/v1"
    30  )
    31  
    32  const (
    33  	InspectContainersEndpoint = "/containers"
    34  
    35  	crioProtocolPrefix    = "cri-o://"
    36  	maxUnixSocketPathSize = len(syscall.RawSockaddrUnix{}.Path)
    37  )
    38  
    39  // CrioClient can get information from docker
    40  type CrioClient struct {
    41  	client        *http.Client
    42  	runtimeClient v1.RuntimeServiceClient
    43  	socketPath    string
    44  }
    45  
    46  // FormatContainerID strips protocol prefix from the container ID
    47  func (c CrioClient) FormatContainerID(ctx context.Context, containerID string) (string, error) {
    48  	if len(containerID) < len(crioProtocolPrefix) {
    49  		return "", errors.Errorf("container id %s is not a crio container id", containerID)
    50  	}
    51  	if containerID[0:len(crioProtocolPrefix)] != crioProtocolPrefix {
    52  		return "", errors.Errorf("expected %s but got %s", crioProtocolPrefix, containerID[0:len(crioProtocolPrefix)])
    53  	}
    54  	return containerID[len(crioProtocolPrefix):], nil
    55  }
    56  
    57  // most of these implementations are copied from https://github.com/cri-o/cri-o/blob/master/internal/client/client.go
    58  
    59  // GetPidFromContainerID fetches PID according to container id
    60  func (c CrioClient) GetPidFromContainerID(ctx context.Context, containerID string) (uint32, error) {
    61  	id, err := c.FormatContainerID(ctx, containerID)
    62  	if err != nil {
    63  		return 0, err
    64  	}
    65  
    66  	req, err := c.getRequest(ctx, InspectContainersEndpoint+"/"+id)
    67  	if err != nil {
    68  		return 0, err
    69  	}
    70  	resp, err := c.client.Do(req)
    71  	if err != nil {
    72  		return 0, err
    73  	}
    74  	defer resp.Body.Close()
    75  	cInfo := make(map[string]interface{})
    76  	if err := json.NewDecoder(resp.Body).Decode(&cInfo); err != nil {
    77  		return 0, err
    78  	}
    79  
    80  	pid := cInfo["pid"]
    81  	if pid, ok := pid.(float64); ok {
    82  		return uint32(pid), nil
    83  	}
    84  
    85  	return 0, errors.New("fail to get pid from container info")
    86  }
    87  
    88  // ContainerKillByContainerID kills container according to container id
    89  func (c CrioClient) ContainerKillByContainerID(ctx context.Context, containerID string) error {
    90  	pid, err := c.GetPidFromContainerID(ctx, containerID)
    91  	if err != nil {
    92  		return err
    93  	}
    94  	return syscall.Kill(int(pid), syscall.SIGKILL)
    95  }
    96  
    97  // ListContainerIDs lists all container IDs
    98  func (c CrioClient) ListContainerIDs(ctx context.Context) ([]string, error) {
    99  	resp, err := c.runtimeClient.ListContainers(ctx, &v1.ListContainersRequest{})
   100  	if err != nil {
   101  		return nil, err
   102  	}
   103  
   104  	var ids []string
   105  	for _, container := range resp.Containers {
   106  		id := fmt.Sprintf("%s%s", crioProtocolPrefix, container.Id)
   107  		ids = append(ids, id)
   108  	}
   109  	return ids, nil
   110  }
   111  
   112  // GetLabelsFromContainerID returns the labels according to container ID
   113  func (c CrioClient) GetLabelsFromContainerID(ctx context.Context, containerID string) (map[string]string, error) {
   114  	id, err := c.FormatContainerID(ctx, containerID)
   115  	if err != nil {
   116  		return nil, err
   117  	}
   118  
   119  	container, err := c.runtimeClient.ContainerStatus(ctx, &v1.ContainerStatusRequest{
   120  		ContainerId: id,
   121  	})
   122  	if err != nil {
   123  		return nil, err
   124  	}
   125  
   126  	return container.Status.Labels, nil
   127  }
   128  
   129  func buildRuntimeServiceClient(endpoint string) (v1.RuntimeServiceClient, error) {
   130  	addr := fmt.Sprintf("unix://%s", endpoint)
   131  	conn, err := grpc.Dial(addr, grpc.WithBlock(), grpc.WithInsecure())
   132  	if err != nil {
   133  		return nil, err
   134  	}
   135  
   136  	client := v1.NewRuntimeServiceClient(conn)
   137  	return client, err
   138  }
   139  
   140  func New(socketPath string) (*CrioClient, error) {
   141  	tr := new(http.Transport)
   142  	if err := configureUnixTransport(tr, "unix", socketPath); err != nil {
   143  		return nil, err
   144  	}
   145  	c := &http.Client{
   146  		Transport: tr,
   147  	}
   148  
   149  	runtimeClient, err := buildRuntimeServiceClient(socketPath)
   150  	if err != nil {
   151  		return nil, err
   152  	}
   153  
   154  	return &CrioClient{
   155  		client:        c,
   156  		runtimeClient: runtimeClient,
   157  		socketPath:    socketPath,
   158  	}, nil
   159  }
   160  
   161  func configureUnixTransport(tr *http.Transport, proto, addr string) error {
   162  	if len(addr) > maxUnixSocketPathSize {
   163  		return errors.Errorf("unix socket path %q is too long", addr)
   164  	}
   165  	// No need for compression in local communications.
   166  	tr.DisableCompression = true
   167  	tr.DialContext = func(_ context.Context, _, _ string) (net.Conn, error) {
   168  		return net.DialTimeout(proto, addr, 32*time.Second)
   169  	}
   170  	return nil
   171  }
   172  
   173  func (c *CrioClient) getRequest(ctx context.Context, path string) (*http.Request, error) {
   174  	req, err := http.NewRequest("GET", path, nil)
   175  	if err != nil {
   176  		return nil, err
   177  	}
   178  	// For local communications over a unix socket, it doesn't matter what
   179  	// the host is. We just need a valid and meaningful host name.
   180  	req.Host = "crio"
   181  	req.URL.Host = c.socketPath
   182  	req.URL.Scheme = "http"
   183  	req = req.WithContext(ctx)
   184  	return req, nil
   185  }
   186