distribution/cmd/digest/main.go
Aaron Lehmann 4c850e7165 Remove tarsum support for digest package
tarsum is not actually used by the registry. Remove support for it.

Convert numerous uses in unit tests to SHA256.

Update docs to remove mentions of tarsums (which were often inaccurate).

Remove tarsum dependency.

Signed-off-by: Aaron Lehmann <aaron.lehmann@docker.com>
2015-12-15 17:22:18 -08:00

97 lines
1.7 KiB
Go

package main
import (
"flag"
"fmt"
"io"
"log"
"os"
"github.com/docker/distribution/digest"
"github.com/docker/distribution/version"
)
var (
algorithm = digest.Canonical
showVersion bool
)
type job struct {
name string
reader io.Reader
}
func init() {
flag.Var(&algorithm, "a", "select the digest algorithm (shorthand)")
flag.Var(&algorithm, "algorithm", "select the digest algorithm")
flag.BoolVar(&showVersion, "version", false, "show the version and exit")
log.SetFlags(0)
log.SetPrefix(os.Args[0] + ": ")
}
func usage() {
fmt.Fprintf(os.Stderr, "usage: %s [files...]\n", os.Args[0])
fmt.Fprintf(os.Stderr, `
Calculate the digest of one or more input files, emitting the result
to standard out. If no files are provided, the digest of stdin will
be calculated.
`)
flag.PrintDefaults()
}
func unsupported() {
log.Fatalf("unsupported digest algorithm: %v", algorithm)
}
func main() {
var jobs []job
flag.Usage = usage
flag.Parse()
if showVersion {
version.PrintVersion()
return
}
var fail bool // if we fail on one item, foul the exit code
if flag.NArg() > 0 {
for _, path := range flag.Args() {
fp, err := os.Open(path)
if err != nil {
log.Printf("%s: %v", path, err)
fail = true
continue
}
defer fp.Close()
jobs = append(jobs, job{name: path, reader: fp})
}
} else {
// just read stdin
jobs = append(jobs, job{name: "-", reader: os.Stdin})
}
digestFn := algorithm.FromReader
if !algorithm.Available() {
unsupported()
}
for _, job := range jobs {
dgst, err := digestFn(job.reader)
if err != nil {
log.Printf("%s: %v", job.name, err)
fail = true
continue
}
fmt.Printf("%v\t%s\n", dgst, job.name)
}
if fail {
os.Exit(1)
}
}