132 lines
3.3 KiB
Go
132 lines
3.3 KiB
Go
/*
|
|
Copyright The containerd Authors.
|
|
|
|
Licensed under the Apache License, Version 2.0 (the "License");
|
|
you may not use this file except in compliance with the License.
|
|
You may obtain a copy of the License at
|
|
|
|
http://www.apache.org/licenses/LICENSE-2.0
|
|
|
|
Unless required by applicable law or agreed to in writing, software
|
|
distributed under the License is distributed on an "AS IS" BASIS,
|
|
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
See the License for the specific language governing permissions and
|
|
limitations under the License.
|
|
*/
|
|
|
|
package apply
|
|
|
|
import (
|
|
"context"
|
|
"fmt"
|
|
"io"
|
|
"time"
|
|
|
|
"github.com/containerd/containerd/content"
|
|
"github.com/containerd/containerd/diff"
|
|
"github.com/containerd/containerd/log"
|
|
"github.com/containerd/containerd/mount"
|
|
digest "github.com/opencontainers/go-digest"
|
|
ocispec "github.com/opencontainers/image-spec/specs-go/v1"
|
|
)
|
|
|
|
// NewFileSystemApplier returns an applier which simply mounts
|
|
// and applies diff onto the mounted filesystem.
|
|
func NewFileSystemApplier(cs content.Provider) diff.Applier {
|
|
return &fsApplier{
|
|
store: cs,
|
|
}
|
|
}
|
|
|
|
type fsApplier struct {
|
|
store content.Provider
|
|
}
|
|
|
|
var emptyDesc = ocispec.Descriptor{}
|
|
|
|
// Apply applies the content associated with the provided digests onto the
|
|
// provided mounts. Archive content will be extracted and decompressed if
|
|
// necessary.
|
|
func (s *fsApplier) Apply(ctx context.Context, desc ocispec.Descriptor, mounts []mount.Mount, opts ...diff.ApplyOpt) (d ocispec.Descriptor, err error) {
|
|
t1 := time.Now()
|
|
defer func() {
|
|
if err == nil {
|
|
log.G(ctx).WithFields(log.Fields{
|
|
"d": time.Since(t1),
|
|
"digest": desc.Digest,
|
|
"size": desc.Size,
|
|
"media": desc.MediaType,
|
|
}).Debugf("diff applied")
|
|
}
|
|
}()
|
|
|
|
var config diff.ApplyConfig
|
|
for _, o := range opts {
|
|
if err := o(ctx, desc, &config); err != nil {
|
|
return emptyDesc, fmt.Errorf("failed to apply config opt: %w", err)
|
|
}
|
|
}
|
|
|
|
ra, err := s.store.ReaderAt(ctx, desc)
|
|
if err != nil {
|
|
return emptyDesc, fmt.Errorf("failed to get reader from content store: %w", err)
|
|
}
|
|
defer ra.Close()
|
|
|
|
var processors []diff.StreamProcessor
|
|
processor := diff.NewProcessorChain(desc.MediaType, content.NewReader(ra))
|
|
processors = append(processors, processor)
|
|
for {
|
|
if processor, err = diff.GetProcessor(ctx, processor, config.ProcessorPayloads); err != nil {
|
|
return emptyDesc, fmt.Errorf("failed to get stream processor for %s: %w", desc.MediaType, err)
|
|
}
|
|
processors = append(processors, processor)
|
|
if processor.MediaType() == ocispec.MediaTypeImageLayer {
|
|
break
|
|
}
|
|
}
|
|
defer processor.Close()
|
|
|
|
digester := digest.Canonical.Digester()
|
|
rc := &readCounter{
|
|
r: io.TeeReader(processor, digester.Hash()),
|
|
}
|
|
|
|
if err := apply(ctx, mounts, rc); err != nil {
|
|
return emptyDesc, err
|
|
}
|
|
|
|
// Read any trailing data
|
|
if _, err := io.Copy(io.Discard, rc); err != nil {
|
|
return emptyDesc, err
|
|
}
|
|
|
|
for _, p := range processors {
|
|
if ep, ok := p.(interface {
|
|
Err() error
|
|
}); ok {
|
|
if err := ep.Err(); err != nil {
|
|
return emptyDesc, err
|
|
}
|
|
}
|
|
}
|
|
return ocispec.Descriptor{
|
|
MediaType: ocispec.MediaTypeImageLayer,
|
|
Size: rc.c,
|
|
Digest: digester.Digest(),
|
|
}, nil
|
|
}
|
|
|
|
type readCounter struct {
|
|
r io.Reader
|
|
c int64
|
|
}
|
|
|
|
func (rc *readCounter) Read(p []byte) (n int, err error) {
|
|
n, err = rc.r.Read(p)
|
|
if n > 0 {
|
|
rc.c += int64(n)
|
|
}
|
|
return
|
|
}
|