github.com/containerd/nerdctl/v2@v2.0.0-beta.5.0.20240520001846-b5758f54fa28/pkg/cmd/container/commit.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 container
    18  
    19  import (
    20  	"context"
    21  	"encoding/json"
    22  	"fmt"
    23  	"strings"
    24  
    25  	"github.com/containerd/containerd"
    26  	"github.com/containerd/log"
    27  	"github.com/containerd/nerdctl/v2/pkg/api/types"
    28  	"github.com/containerd/nerdctl/v2/pkg/idutil/containerwalker"
    29  	"github.com/containerd/nerdctl/v2/pkg/imgutil/commit"
    30  	"github.com/containerd/nerdctl/v2/pkg/referenceutil"
    31  )
    32  
    33  // Commit will commit a container’s file changes or settings into a new image.
    34  func Commit(ctx context.Context, client *containerd.Client, rawRef string, req string, options types.ContainerCommitOptions) error {
    35  	named, err := referenceutil.ParseDockerRef(rawRef)
    36  	if err != nil {
    37  		return err
    38  	}
    39  
    40  	changes, err := parseChanges(options.Change)
    41  	if err != nil {
    42  		return err
    43  	}
    44  
    45  	opts := &commit.Opts{
    46  		Author:  options.Author,
    47  		Message: options.Message,
    48  		Ref:     named.String(),
    49  		Pause:   options.Pause,
    50  		Changes: changes,
    51  	}
    52  
    53  	walker := &containerwalker.ContainerWalker{
    54  		Client: client,
    55  		OnFound: func(ctx context.Context, found containerwalker.Found) error {
    56  			if found.MatchCount > 1 {
    57  				return fmt.Errorf("multiple IDs found with provided prefix: %s", found.Req)
    58  			}
    59  			imageID, err := commit.Commit(ctx, client, found.Container, opts)
    60  			if err != nil {
    61  				return err
    62  			}
    63  			_, err = fmt.Fprintln(options.Stdout, imageID)
    64  			return err
    65  		},
    66  	}
    67  	n, err := walker.Walk(ctx, req)
    68  	if err != nil {
    69  		return err
    70  	} else if n == 0 {
    71  		return fmt.Errorf("no such container %s", req)
    72  	}
    73  	return nil
    74  }
    75  
    76  func parseChanges(userChanges []string) (commit.Changes, error) {
    77  	const (
    78  		// XXX: Where can I get a constants for this?
    79  		commandDirective    = "CMD"
    80  		entrypointDirective = "ENTRYPOINT"
    81  	)
    82  	if userChanges == nil {
    83  		return commit.Changes{}, nil
    84  	}
    85  	var changes commit.Changes
    86  	for _, change := range userChanges {
    87  		if change == "" {
    88  			return commit.Changes{}, fmt.Errorf("received an empty value in change flag")
    89  		}
    90  		changeFields := strings.Fields(change)
    91  
    92  		switch changeFields[0] {
    93  		case commandDirective:
    94  			var overrideCMD []string
    95  			if err := json.Unmarshal([]byte(change[len(changeFields[0]):]), &overrideCMD); err != nil {
    96  				return commit.Changes{}, fmt.Errorf("malformed json in change flag value %q", change)
    97  			}
    98  			if changes.CMD != nil {
    99  				log.L.Warn("multiple change flags supplied for the CMD directive, overriding with last supplied")
   100  			}
   101  			changes.CMD = overrideCMD
   102  		case entrypointDirective:
   103  			var overrideEntrypoint []string
   104  			if err := json.Unmarshal([]byte(change[len(changeFields[0]):]), &overrideEntrypoint); err != nil {
   105  				return commit.Changes{}, fmt.Errorf("malformed json in change flag value %q", change)
   106  			}
   107  			if changes.Entrypoint != nil {
   108  				log.L.Warnf("multiple change flags supplied for the Entrypoint directive, overriding with last supplied")
   109  			}
   110  			changes.Entrypoint = overrideEntrypoint
   111  		default: // TODO: Support the rest of the change directives
   112  			return commit.Changes{}, fmt.Errorf("unknown change directive %q", changeFields[0])
   113  		}
   114  	}
   115  	return changes, nil
   116  }