1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
|
package fetcher
import (
"context"
"fmt"
"net/url"
"go.alanpearce.eu/searchix/internal/config"
"go.alanpearce.eu/searchix/internal/index"
"github.com/pkg/errors"
"go.alanpearce.eu/x/log"
)
type NixpkgsChannelFetcher struct {
Source *config.Source
Logger *log.Logger
}
func makeChannelURL(channel string, subPath string) (string, error) {
url, err := url.JoinPath("https://channels.nixos.org/", channel, subPath)
return url, errors.WithMessagef(err, "error creating URL")
}
func NewNixpkgsChannelFetcher(
source *config.Source,
logger *log.Logger,
) (*NixpkgsChannelFetcher, error) {
switch source.Importer {
case config.Options, config.Packages:
return &NixpkgsChannelFetcher{
Source: source,
Logger: logger,
}, nil
default:
return nil, fmt.Errorf("unsupported importer type %s", source.Importer)
}
}
const (
revisionFilename = "git-revision"
optionsFilename = "options.json.br"
packagesFileName = "packages.json.br"
)
func (i *NixpkgsChannelFetcher) FetchIfNeeded(
ctx context.Context,
sourceMeta *index.SourceMeta,
) (f FetchedFiles, err error) {
filesToFetch := make([]string, 2)
filesToFetch[0] = revisionFilename
switch i.Source.Importer {
case config.Packages:
filesToFetch[1] = packagesFileName
case config.Options:
filesToFetch[1] = optionsFilename
}
var fetchURL string
for _, filename := range filesToFetch {
fetchURL, err = makeChannelURL(i.Source.Channel, filename)
if err != nil {
return
}
i.Logger.Debug("attempting to fetch file", "url", fetchURL)
body, mtime, err := fetchFileIfNeeded(ctx, i.Logger, sourceMeta.Updated, fetchURL)
if err != nil {
i.Logger.Warn("failed to fetch file", "url", fetchURL, "error", err)
return f, err
}
// don't bother to issue requests for the later files
if mtime.Before(sourceMeta.Updated) {
break
}
sourceMeta.Updated = mtime
switch filename {
case revisionFilename:
f.Revision = body
case optionsFilename:
f.Options = body
case packagesFileName:
f.Packages = body
default:
return f, errors.Errorf("unknown file kind %s", filename)
}
}
return
}
|