Files
ociclient/getman.go

91 lines
2.2 KiB
Go

package repocli
import (
"bytes"
"context"
"errors"
"fmt"
"net/http"
"strconv"
"strings"
)
func (cli *Client) GetManifest(ctx context.Context, rawrepo, tag string) (bool, string, []byte, error) {
var err error
var exist bool
var mime string
var man []byte
ref, err := NewRepository(rawrepo)
if err != nil {
return exist, mime, man, err
}
uri := ref.Manifest(tag)
req, err := http.NewRequestWithContext(ctx, http.MethodGet, uri, nil)
if err != nil {
return exist, mime, man, err
}
req.Header.Set("User-Agent", cli.userAgent)
req.Header.Set("Accept", "*/*")
resp, err := cli.httpClient.Do(req)
if err != nil {
return exist, mime, man, err
}
defer resp.Body.Close()
if resp.StatusCode == http.StatusNotFound {
return exist, mime, man, err
}
if resp.StatusCode != http.StatusOK {
err := fmt.Errorf("Unxected response code %s", resp.Status)
return exist, mime, man, err
}
contentLength := resp.Header.Get("Content-Length")
if contentLength == "" {
err = errors.New("Empty Content-Length header")
return exist, mime, man, err
}
manSize, err := strconv.ParseInt(contentLength, 10, 64)
if err != nil {
return exist, mime, man, err
}
mime = resp.Header.Get("Content-Type")
if mime == "" {
err := fmt.Errorf("Empty MIME type declaration")
return exist, mime, man, err
}
buffer := bytes.NewBuffer(nil)
recSize, err := Copy(ctx, buffer, resp.Body)
if manSize != recSize {
err := fmt.Errorf("Mismatch declared and actual body size, %d and %d", manSize, recSize)
return exist, mime, man, err
}
man = buffer.Bytes()
csum := resp.Header.Get("Docker-Content-Digest")
if csum == "" {
err := fmt.Errorf("Empty digest declaration")
return exist, mime, man, err
}
csum = strings.ToLower(csum)
switch DigestType(csum) {
case SHA256:
if csum != SHA256Digest(man) {
err := fmt.Errorf("Mismatch digest and actual declaration")
return exist, mime, man, err
}
case SHA512:
if csum != SHA256Digest(man) {
err := fmt.Errorf("Mismatch digest and actual declaration")
return exist, mime, man, err
}
default:
err := fmt.Errorf("Unknown digest type: %s", csum)
return exist, mime, man, err
}
exist = true
return exist, mime, man, err
}