github.com/uber/kraken@v0.1.4/utils/dockerutil/dockerutil.go (about)

     1  // Copyright (c) 2016-2019 Uber Technologies, Inc.
     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  package dockerutil
    15  
    16  import (
    17  	"errors"
    18  	"fmt"
    19  	"io"
    20  	"io/ioutil"
    21  
    22  	"github.com/uber/kraken/core"
    23  	"github.com/docker/distribution"
    24  	"github.com/docker/distribution/manifest/schema2"
    25  )
    26  
    27  // ParseManifestV2 returns a parsed v2 manifest and its digest
    28  func ParseManifestV2(r io.Reader) (distribution.Manifest, core.Digest, error) {
    29  	b, err := ioutil.ReadAll(r)
    30  	if err != nil {
    31  		return nil, core.Digest{}, fmt.Errorf("read: %s", err)
    32  	}
    33  	manifest, desc, err := distribution.UnmarshalManifest(schema2.MediaTypeManifest, b)
    34  	if err != nil {
    35  		return nil, core.Digest{}, fmt.Errorf("unmarshal manifest: %s", err)
    36  	}
    37  	deserializedManifest, ok := manifest.(*schema2.DeserializedManifest)
    38  	if !ok {
    39  		return nil, core.Digest{}, errors.New("expected schema2.DeserializedManifest")
    40  	}
    41  	version := deserializedManifest.Manifest.Versioned.SchemaVersion
    42  	if version != 2 {
    43  		return nil, core.Digest{}, fmt.Errorf("unsupported manifest version: %d", version)
    44  	}
    45  	d, err := core.ParseSHA256Digest(string(desc.Digest))
    46  	if err != nil {
    47  		return nil, core.Digest{}, fmt.Errorf("parse digest: %s", err)
    48  	}
    49  	return manifest, d, nil
    50  }
    51  
    52  // GetManifestReferences returns a list of references by a V2 manifest
    53  func GetManifestReferences(manifest distribution.Manifest) ([]core.Digest, error) {
    54  	var refs []core.Digest
    55  	for _, desc := range manifest.References() {
    56  		d, err := core.ParseSHA256Digest(string(desc.Digest))
    57  		if err != nil {
    58  			return nil, fmt.Errorf("parse digest: %s", err)
    59  		}
    60  		refs = append(refs, d)
    61  	}
    62  	return refs, nil
    63  }