kraken

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 blobserver
15

16
import (
17
	"net/http"
18
	"os"
19
	"strconv"
20
	"strings"
21

22
	"github.com/uber/kraken/core"
23
	"github.com/uber/kraken/lib/store"
24
	"github.com/uber/kraken/utils/handler"
25
)
26

27
// parseContentRange parses start / end integers from a Content-Range header.
28
func parseContentRange(h http.Header) (start, end int64, err error) {
29
	contentRange := h.Get("Content-Range")
30
	if len(contentRange) == 0 {
31
		return 0, 0, handler.Errorf("no Content-Range header").Status(http.StatusBadRequest)
32
	}
33
	parts := strings.Split(contentRange, "-")
34
	if len(parts) != 2 {
35
		return 0, 0, handler.Errorf(
36
			"cannot parse Content-Range header %q: expected format \"start-end\"", contentRange).
37
			Status(http.StatusBadRequest)
38
	}
39
	start, err = strconv.ParseInt(parts[0], 10, 64)
40
	if err != nil {
41
		return 0, 0, handler.Errorf(
42
			"cannot parse start of range in Content-Range header %q: %s", contentRange, err).
43
			Status(http.StatusBadRequest)
44
	}
45
	end, err = strconv.ParseInt(parts[1], 10, 64)
46
	if err != nil {
47
		return 0, 0, handler.Errorf(
48
			"cannot parse end of range in Content-Range header %q: %s", contentRange, err).
49
			Status(http.StatusBadRequest)
50
	}
51
	// Note, no need to check for negative because the "-" would cause the
52
	// Split check to fail.
53
	return start, end, nil
54
}
55

56
// blobExists returns true if cas has a cached blob for d.
57
func blobExists(cas *store.CAStore, d core.Digest) (bool, error) {
58
	if _, err := cas.GetCacheFileStat(d.Hex()); err != nil {
59
		if os.IsNotExist(err) {
60
			return false, nil
61
		}
62
		return false, handler.Errorf("cache file stat: %s", err)
63
	}
64
	return true, nil
65
}
66

67
func setUploadLocation(w http.ResponseWriter, uid string) {
68
	w.Header().Set("Location", uid)
69
}
70

71
func setContentLength(w http.ResponseWriter, n int) {
72
	w.Header().Set("Content-Length", strconv.Itoa(n))
73
}
74

75
func setOctetStreamContentType(w http.ResponseWriter) {
76
	w.Header().Set("Content-Type", "application/octet-stream-v1")
77
}
78