1package getter
2
3import (
4	"fmt"
5	"net/url"
6	"strings"
7)
8
9// S3Detector implements Detector to detect S3 URLs and turn
10// them into URLs that the S3 getter can understand.
11type S3Detector struct{}
12
13func (d *S3Detector) Detect(src, _ string) (string, bool, error) {
14	if len(src) == 0 {
15		return "", false, nil
16	}
17
18	if strings.Contains(src, ".amazonaws.com/") {
19		return d.detectHTTP(src)
20	}
21
22	return "", false, nil
23}
24
25func (d *S3Detector) detectHTTP(src string) (string, bool, error) {
26	parts := strings.Split(src, "/")
27	if len(parts) < 2 {
28		return "", false, fmt.Errorf(
29			"URL is not a valid S3 URL")
30	}
31
32	hostParts := strings.Split(parts[0], ".")
33	if len(hostParts) == 3 {
34		return d.detectPathStyle(hostParts[0], parts[1:])
35	} else if len(hostParts) == 4 {
36		return d.detectVhostStyle(hostParts[1], hostParts[0], parts[1:])
37	} else {
38		return "", false, fmt.Errorf(
39			"URL is not a valid S3 URL")
40	}
41}
42
43func (d *S3Detector) detectPathStyle(region string, parts []string) (string, bool, error) {
44	urlStr := fmt.Sprintf("https://%s.amazonaws.com/%s", region, strings.Join(parts, "/"))
45	url, err := url.Parse(urlStr)
46	if err != nil {
47		return "", false, fmt.Errorf("error parsing S3 URL: %s", err)
48	}
49
50	return "s3::" + url.String(), true, nil
51}
52
53func (d *S3Detector) detectVhostStyle(region, bucket string, parts []string) (string, bool, error) {
54	urlStr := fmt.Sprintf("https://%s.amazonaws.com/%s/%s", region, bucket, strings.Join(parts, "/"))
55	url, err := url.Parse(urlStr)
56	if err != nil {
57		return "", false, fmt.Errorf("error parsing S3 URL: %s", err)
58	}
59
60	return "s3::" + url.String(), true, nil
61}
62