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| 1 | +// Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. |
| 2 | +// SPDX-License-Identifier: Apache-2.0 |
| 3 | + |
| 4 | +package bundle |
| 5 | + |
| 6 | +//go:generate mockgen -destination=mock_archiver.go -package=bundle github.com/aws-robotics/aws-robomaker-bundle-support-library/pkg/3p/archiver Archiver |
| 7 | + |
| 8 | +import ( |
| 9 | + "archive/tar" |
| 10 | + "compress/gzip" |
| 11 | + "errors" |
| 12 | + "fmt" |
| 13 | + "github.com/aws-robotics/aws-robomaker-bundle-support-library/pkg/fs" |
| 14 | + "io" |
| 15 | +) |
| 16 | + |
| 17 | +const ( |
| 18 | + versionFileName = "version" |
| 19 | + defaultFileMode fs.FileMode = 0755 |
| 20 | +) |
| 21 | + |
| 22 | +// archive's responsibility is to be able to Extract bundles of all versions, v1, v2, etc. |
| 23 | +type archive struct { |
| 24 | + version string |
| 25 | + inputStream io.ReadSeeker |
| 26 | + bundleProcessor bundleProcessor |
| 27 | +} |
| 28 | + |
| 29 | +func newBundleArchive(inputStream io.ReadSeeker) (*archive, error) { |
| 30 | + // read version to determine bundle version |
| 31 | + tarReader := tarReaderFromStream(inputStream) |
| 32 | + version, versionErr := readVersionFromBundle(tarReader) |
| 33 | + |
| 34 | + if versionErr != nil { |
| 35 | + return nil, fmt.Errorf("unable to read version from bundle: %v", versionErr) |
| 36 | + } |
| 37 | + |
| 38 | + // get the appropriate bundle processor for the version |
| 39 | + bundleProcessor := processorForVersion(version) |
| 40 | + if bundleProcessor == nil { |
| 41 | + return nil, fmt.Errorf("unsuppported bundle processor version: %s", version) |
| 42 | + } |
| 43 | + |
| 44 | + // reset seek position to start of the stream and init with the stream |
| 45 | + inputStream.Seek(0, io.SeekStart) |
| 46 | + return &archive{ |
| 47 | + version: version, |
| 48 | + inputStream: inputStream, |
| 49 | + bundleProcessor: bundleProcessor, |
| 50 | + }, nil |
| 51 | +} |
| 52 | + |
| 53 | +// What version is this bundle? |
| 54 | +func (b *archive) Version() string { |
| 55 | + return b.version |
| 56 | +} |
| 57 | + |
| 58 | +// Extract everything into the cache |
| 59 | +func (b *archive) Extract(bundleStore Cache) (Bundle, error) { |
| 60 | + return b.bundleProcessor.extract(b.inputStream, bundleStore) |
| 61 | +} |
| 62 | + |
| 63 | +func readVersionFromBundle(tarReader *tar.Reader) (string, error) { |
| 64 | + header, headerErr := tarReader.Next() |
| 65 | + if headerErr != nil { |
| 66 | + fmt.Printf("bundleError parsing tar: %v", headerErr) |
| 67 | + return "", headerErr |
| 68 | + } |
| 69 | + |
| 70 | + if header.Name != versionFileName { |
| 71 | + err := errors.New("invalid bundle format, first file should be a version file") |
| 72 | + return "", err |
| 73 | + } |
| 74 | + |
| 75 | + versionData := make([]byte, header.Size) |
| 76 | + _, readVersionErr := tarReader.Read(versionData) |
| 77 | + // We need to read a second time to get the io.EOF message |
| 78 | + _, readVersionErr = tarReader.Read(nil) |
| 79 | + if readVersionErr != io.EOF { |
| 80 | + return "", fmt.Errorf("unable to read version: %v", readVersionErr) |
| 81 | + } |
| 82 | + |
| 83 | + return string(versionData), nil |
| 84 | +} |
| 85 | + |
| 86 | +func tarReaderFromStream(inputStream io.ReadSeeker) *tar.Reader { |
| 87 | + var tarReader *tar.Reader |
| 88 | + |
| 89 | + // try as a gzReader |
| 90 | + gzReader, gzErr := gzip.NewReader(inputStream) |
| 91 | + if gzErr == nil { |
| 92 | + // this is a valid gz file |
| 93 | + // create the tar reader from the gzReader |
| 94 | + tarReader = tar.NewReader(gzReader) |
| 95 | + } else { |
| 96 | + // it wasn't a gz file, let's try to create the tar reader from the input stream |
| 97 | + inputStream.Seek(0, io.SeekStart) |
| 98 | + tarReader = tar.NewReader(inputStream) |
| 99 | + } |
| 100 | + return tarReader |
| 101 | +} |
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