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  	"google.golang.org/grpc/credentials/insecure"
    28  
    29  	"github.com/pkg/errors"
    30  	"google.golang.org/grpc"
    31  	v1 "k8s.io/cri-api/pkg/apis/runtime/v1"
    32  )
    33  
    34  const (
    35  	InspectContainersEndpoint = "/containers"
    36  
    37  	crioProtocolPrefix    = "cri-o://"
    38  	maxUnixSocketPathSize = len(syscall.RawSockaddrUnix{}.Path)
    39  )
    40  
    41  // CrioClient can get information from docker
    42  type CrioClient struct {
    43  	client        *http.Client
    44  	runtimeClient v1.RuntimeServiceClient
    45  	socketPath    string
    46  }
    47  
    48  // FormatContainerID strips protocol prefix from the container ID
    49  func (c CrioClient) FormatContainerID(ctx context.Context, containerID string) (string, error) {
    50  	if len(containerID) < len(crioProtocolPrefix) {
    51  		return "", errors.Errorf("container id %s is not a crio container id", containerID)
    52  	}
    53  	if containerID[0:len(crioProtocolPrefix)] != crioProtocolPrefix {
    54  		return "", errors.Errorf("expected %s but got %s", crioProtocolPrefix, containerID[0:len(crioProtocolPrefix)])
    55  	}
    56  	return containerID[len(crioProtocolPrefix):], nil
    57  }
    58  
    59  // most of these implementations are copied from https://github.com/cri-o/cri-o/blob/master/internal/client/client.go
    60  
    61  // GetPidFromContainerID fetches PID according to container id
    62  func (c CrioClient) GetPidFromContainerID(ctx context.Context, containerID string) (uint32, error) {
    63  	id, err := c.FormatContainerID(ctx, containerID)
    64  	if err != nil {
    65  		return 0, err
    66  	}
    67  
    68  	req, err := c.getRequest(ctx, InspectContainersEndpoint+"/"+id)
    69  	if err != nil {
    70  		return 0, err
    71  	}
    72  	resp, err := c.client.Do(req)
    73  	if err != nil {
    74  		return 0, err
    75  	}
    76  	defer resp.Body.Close()
    77  	cInfo := make(map[string]interface{})
    78  	if err := json.NewDecoder(resp.Body).Decode(&cInfo); err != nil {
    79  		return 0, err
    80  	}
    81  
    82  	pid := cInfo["pid"]
    83  	if pid, ok := pid.(float64); ok {
    84  		return uint32(pid), nil
    85  	}
    86  
    87  	return 0, errors.New("fail to get pid from container info")
    88  }
    89  
    90  // ContainerKillByContainerID kills container according to container id
    91  func (c CrioClient) ContainerKillByContainerID(ctx context.Context, containerID string) error {
    92  	pid, err := c.GetPidFromContainerID(ctx, containerID)
    93  	if err != nil {
    94  		return err
    95  	}
    96  	return syscall.Kill(int(pid), syscall.SIGKILL)
    97  }
    98  
    99  // ListContainerIDs lists all container IDs
   100  func (c CrioClient) ListContainerIDs(ctx context.Context) ([]string, error) {
   101  	resp, err := c.runtimeClient.ListContainers(ctx, &v1.ListContainersRequest{})
   102  	if err != nil {
   103  		return nil, err
   104  	}
   105  
   106  	var ids []string
   107  	for _, container := range resp.Containers {
   108  		id := fmt.Sprintf("%s%s", crioProtocolPrefix, container.Id)
   109  		ids = append(ids, id)
   110  	}
   111  	return ids, nil
   112  }
   113  
   114  // GetLabelsFromContainerID returns the labels according to container ID
   115  func (c CrioClient) GetLabelsFromContainerID(ctx context.Context, containerID string) (map[string]string, error) {
   116  	id, err := c.FormatContainerID(ctx, containerID)
   117  	if err != nil {
   118  		return nil, err
   119  	}
   120  
   121  	container, err := c.runtimeClient.ContainerStatus(ctx, &v1.ContainerStatusRequest{
   122  		ContainerId: id,
   123  	})
   124  	if err != nil {
   125  		return nil, err
   126  	}
   127  
   128  	return container.Status.Labels, nil
   129  }
   130  
   131  func buildRuntimeServiceClient(endpoint string) (v1.RuntimeServiceClient, error) {
   132  	addr := fmt.Sprintf("unix://%s", endpoint)
   133  	conn, err := grpc.Dial(addr, grpc.WithBlock(), grpc.WithTransportCredentials(insecure.NewCredentials()))
   134  	if err != nil {
   135  		return nil, err
   136  	}
   137  
   138  	client := v1.NewRuntimeServiceClient(conn)
   139  	return client, err
   140  }
   141  
   142  func New(socketPath string) (*CrioClient, error) {
   143  	tr := new(http.Transport)
   144  	if err := configureUnixTransport(tr, "unix", socketPath); err != nil {
   145  		return nil, err
   146  	}
   147  	c := &http.Client{
   148  		Transport: tr,
   149  	}
   150  
   151  	runtimeClient, err := buildRuntimeServiceClient(socketPath)
   152  	if err != nil {
   153  		return nil, err
   154  	}
   155  
   156  	return &CrioClient{
   157  		client:        c,
   158  		runtimeClient: runtimeClient,
   159  		socketPath:    socketPath,
   160  	}, nil
   161  }
   162  
   163  func configureUnixTransport(tr *http.Transport, proto, addr string) error {
   164  	if len(addr) > maxUnixSocketPathSize {
   165  		return errors.Errorf("unix socket path %q is too long", addr)
   166  	}
   167  	// No need for compression in local communications.
   168  	tr.DisableCompression = true
   169  	tr.DialContext = func(_ context.Context, _, _ string) (net.Conn, error) {
   170  		return net.DialTimeout(proto, addr, 32*time.Second)
   171  	}
   172  	return nil
   173  }
   174  
   175  func (c *CrioClient) getRequest(ctx context.Context, path string) (*http.Request, error) {
   176  	req, err := http.NewRequest("GET", path, nil)
   177  	if err != nil {
   178  		return nil, err
   179  	}
   180  	// For local communications over a unix socket, it doesn't matter what
   181  	// the host is. We just need a valid and meaningful host name.
   182  	req.Host = "crio"
   183  	req.URL.Host = c.socketPath
   184  	req.URL.Scheme = "http"
   185  	req = req.WithContext(ctx)
   186  	return req, nil
   187  }
   188