| 1 | package migrations |
| 2 | |
| 3 | import ( |
| 4 | "archive/tar" |
| 5 | "archive/zip" |
| 6 | "compress/gzip" |
| 7 | "errors" |
| 8 | "fmt" |
| 9 | "io" |
| 10 | "os" |
| 11 | ) |
| 12 | |
| 13 | func unpackArchive(arcPath, atype, root, name, out string) error { |
| 14 | var err error |
| 15 | switch atype { |
| 16 | case "tar.gz": |
| 17 | err = unpackTgz(arcPath, root, name, out) |
| 18 | case "zip": |
| 19 | err = unpackZip(arcPath, root, name, out) |
| 20 | default: |
| 21 | err = fmt.Errorf("unrecognized archive type: %s", atype) |
| 22 | } |
| 23 | if err != nil { |
| 24 | return err |
| 25 | } |
| 26 | return nil |
| 27 | } |
| 28 | |
| 29 | func unpackTgz(arcPath, root, name, out string) error { |
| 30 | fi, err := os.Open(arcPath) |
| 31 | if err != nil { |
| 32 | return fmt.Errorf("cannot open archive file: %w", err) |
| 33 | } |
| 34 | defer fi.Close() |
| 35 | |
| 36 | gzr, err := gzip.NewReader(fi) |
| 37 | if err != nil { |
| 38 | return fmt.Errorf("error opening gzip reader: %w", err) |
| 39 | } |
| 40 | defer gzr.Close() |
| 41 | |
| 42 | var bin io.Reader |
| 43 | tarr := tar.NewReader(gzr) |
| 44 | |
| 45 | lookFor := root + "/" + name |
| 46 | for { |
| 47 | th, err := tarr.Next() |
| 48 | if err != nil { |
| 49 | if err == io.EOF { |
| 50 | break |
| 51 | } |
| 52 | return fmt.Errorf("cannot read archive: %w", err) |
| 53 | } |
| 54 | |
| 55 | if th.Name == lookFor { |
| 56 | bin = tarr |
| 57 | break |
| 58 | } |
| 59 | } |
| 60 | |
| 61 | if bin == nil { |
| 62 | return errors.New("no binary found in archive") |
| 63 | } |
| 64 | |
| 65 | return writeToPath(bin, out) |
| 66 | } |
| 67 | |
| 68 | func unpackZip(arcPath, root, name, out string) error { |
| 69 | zipr, err := zip.OpenReader(arcPath) |
| 70 | if err != nil { |
| 71 | return fmt.Errorf("error opening zip reader: %w", err) |
| 72 | } |
| 73 | defer zipr.Close() |
| 74 | |
| 75 | lookFor := root + "/" + name |
| 76 | var bin io.ReadCloser |
| 77 | for _, fis := range zipr.File { |
| 78 | if fis.Name == lookFor { |
| 79 | rc, err := fis.Open() |
| 80 | if err != nil { |
| 81 | return fmt.Errorf("error extracting binary from archive: %w", err) |
| 82 | } |
| 83 | |
| 84 | bin = rc |
| 85 | break |
| 86 | } |
| 87 | } |
| 88 | |
| 89 | if bin == nil { |
| 90 | return errors.New("no binary found in archive") |
| 91 | } |
| 92 | |
| 93 | return writeToPath(bin, out) |
| 94 | } |
| 95 | |
| 96 | func writeToPath(rc io.Reader, out string) error { |
| 97 | binfi, err := os.Create(out) |
| 98 | if err != nil { |
| 99 | return fmt.Errorf("error creating output file '%s': %w", out, err) |
| 100 | } |
| 101 | defer binfi.Close() |
| 102 | |
| 103 | _, err = io.Copy(binfi, rc) |
| 104 | |
| 105 | return err |
| 106 | } |