github.com/rawahars/moby@v24.0.4+incompatible/daemon/containerd/handlers.go (about)

     1  package containerd
     2  
     3  import (
     4  	"context"
     5  
     6  	"github.com/containerd/containerd/content"
     7  	cerrdefs "github.com/containerd/containerd/errdefs"
     8  	containerdimages "github.com/containerd/containerd/images"
     9  	ocispec "github.com/opencontainers/image-spec/specs-go/v1"
    10  )
    11  
    12  // walkPresentChildren is a simple wrapper for containerdimages.Walk with presentChildrenHandler.
    13  // This is only a convenient helper to reduce boilerplate.
    14  func (i *ImageService) walkPresentChildren(ctx context.Context, target ocispec.Descriptor, f func(context.Context, ocispec.Descriptor) error) error {
    15  	store := i.client.ContentStore()
    16  	return containerdimages.Walk(ctx, presentChildrenHandler(store, containerdimages.HandlerFunc(
    17  		func(ctx context.Context, desc ocispec.Descriptor) ([]ocispec.Descriptor, error) {
    18  			return nil, f(ctx, desc)
    19  		})), target)
    20  }
    21  
    22  // presentChildrenHandler is a handler wrapper which traverses all children
    23  // descriptors that are present in the store and calls specified handler.
    24  func presentChildrenHandler(store content.Store, h containerdimages.HandlerFunc) containerdimages.HandlerFunc {
    25  	return func(ctx context.Context, desc ocispec.Descriptor) ([]ocispec.Descriptor, error) {
    26  		_, err := store.Info(ctx, desc.Digest)
    27  		if err != nil {
    28  			if cerrdefs.IsNotFound(err) {
    29  				return nil, nil
    30  			}
    31  			return nil, err
    32  		}
    33  
    34  		children, err := h(ctx, desc)
    35  		if err != nil {
    36  			return nil, err
    37  		}
    38  
    39  		c, err := containerdimages.Children(ctx, store, desc)
    40  		if err != nil {
    41  			return nil, err
    42  		}
    43  		children = append(children, c...)
    44  
    45  		return children, nil
    46  	}
    47  }