github.com/containerd/nerdctl@v1.7.7/pkg/clientutil/client.go (about)

     1  /*
     2     Copyright The containerd Authors.
     3  
     4     Licensed under the Apache License, Version 2.0 (the "License");
     5     you may not use this file except in compliance with the License.
     6     You may obtain a copy of the License at
     7  
     8         http://www.apache.org/licenses/LICENSE-2.0
     9  
    10     Unless required by applicable law or agreed to in writing, software
    11     distributed under the License is distributed on an "AS IS" BASIS,
    12     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13     See the License for the specific language governing permissions and
    14     limitations under the License.
    15  */
    16  
    17  package clientutil
    18  
    19  import (
    20  	"context"
    21  	"fmt"
    22  	"os"
    23  	"path/filepath"
    24  	"runtime"
    25  	"strings"
    26  
    27  	"github.com/containerd/containerd"
    28  	"github.com/containerd/containerd/namespaces"
    29  	"github.com/containerd/log"
    30  	"github.com/containerd/nerdctl/pkg/platformutil"
    31  	"github.com/containerd/nerdctl/pkg/systemutil"
    32  	"github.com/containerd/platforms"
    33  	"github.com/opencontainers/go-digest"
    34  )
    35  
    36  func NewClient(ctx context.Context, namespace, address string, opts ...containerd.ClientOpt) (*containerd.Client, context.Context, context.CancelFunc, error) {
    37  
    38  	ctx = namespaces.WithNamespace(ctx, namespace)
    39  
    40  	address = strings.TrimPrefix(address, "unix://")
    41  	const dockerContainerdaddress = "/var/run/docker/containerd/containerd.sock"
    42  	if err := systemutil.IsSocketAccessible(address); err != nil {
    43  		if systemutil.IsSocketAccessible(dockerContainerdaddress) == nil {
    44  			err = fmt.Errorf("cannot access containerd socket %q (hint: try running with `--address %s` to connect to Docker-managed containerd): %w", address, dockerContainerdaddress, err)
    45  		} else {
    46  			err = fmt.Errorf("cannot access containerd socket %q: %w", address, err)
    47  		}
    48  		return nil, nil, nil, err
    49  	}
    50  	client, err := containerd.New(address, opts...)
    51  	if err != nil {
    52  		return nil, nil, nil, err
    53  	}
    54  	var cancel context.CancelFunc
    55  	ctx, cancel = context.WithCancel(ctx)
    56  	return client, ctx, cancel, nil
    57  }
    58  
    59  func NewClientWithPlatform(ctx context.Context, namespace, address, platform string, clientOpts ...containerd.ClientOpt) (*containerd.Client, context.Context, context.CancelFunc, error) {
    60  	if platform != "" {
    61  		if canExec, canExecErr := platformutil.CanExecProbably(platform); !canExec {
    62  			warn := fmt.Sprintf("Platform %q seems incompatible with the host platform %q. If you see \"exec format error\", see https://github.com/containerd/nerdctl/blob/main/docs/multi-platform.md",
    63  				platform, platforms.DefaultString())
    64  			if canExecErr != nil {
    65  				log.L.WithError(canExecErr).Warn(warn)
    66  			} else {
    67  				log.L.Warn(warn)
    68  			}
    69  		}
    70  		platformParsed, err := platforms.Parse(platform)
    71  		if err != nil {
    72  			return nil, nil, nil, err
    73  		}
    74  		platformM := platforms.Only(platformParsed)
    75  		clientOpts = append(clientOpts, containerd.WithDefaultPlatform(platformM))
    76  	}
    77  	return NewClient(ctx, namespace, address, clientOpts...)
    78  }
    79  
    80  // DataStore returns a string like "/var/lib/nerdctl/1935db59".
    81  // "1935db9" is from `$(echo -n "/run/containerd/containerd.sock" | sha256sum | cut -c1-8)`
    82  // on Windows it will return "%PROGRAMFILES%/nerdctl/1935db59"
    83  func DataStore(dataRoot, address string) (string, error) {
    84  	if err := os.MkdirAll(dataRoot, 0700); err != nil {
    85  		return "", err
    86  	}
    87  	addrHash, err := getAddrHash(address)
    88  	if err != nil {
    89  		return "", err
    90  	}
    91  	dataStore := filepath.Join(dataRoot, addrHash)
    92  	if err := os.MkdirAll(dataStore, 0700); err != nil {
    93  		return "", err
    94  	}
    95  	return dataStore, nil
    96  }
    97  
    98  func getAddrHash(addr string) (string, error) {
    99  	const addrHashLen = 8
   100  
   101  	if runtime.GOOS != "windows" {
   102  		addr = strings.TrimPrefix(addr, "unix://")
   103  
   104  		var err error
   105  		addr, err = filepath.EvalSymlinks(addr)
   106  		if err != nil {
   107  			return "", err
   108  		}
   109  	}
   110  
   111  	d := digest.SHA256.FromString(addr)
   112  	h := d.Encoded()[0:addrHashLen]
   113  	return h, nil
   114  }