aboutsummaryrefslogtreecommitdiff
path: root/plugin/kubernetes/parse.go
blob: 4690c814b114b2006a843bc681d5a7ae19c2c7f1 (plain) (blame)
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
95
96
97
98
99
100
101
102
103
package kubernetes

import (
	"github.com/coredns/coredns/plugin/pkg/dnsutil"

	"github.com/miekg/dns"
)

type recordRequest struct {
	// The named port from the kubernetes DNS spec, this is the service part (think _https) from a well formed
	// SRV record.
	port string
	// The protocol is usually _udp or _tcp (if set), and comes from the protocol part of a well formed
	// SRV record.
	protocol string
	endpoint string
	// The servicename used in Kubernetes.
	service string
	// The namespace used in Kubernetes.
	namespace string
	// A each name can be for a pod or a service, here we track what we've seen, either "pod" or "service".
	podOrSvc string
}

// parseRequest parses the qname to find all the elements we need for querying k8s. Anything
// that is not parsed will have the wildcard "*" value (except r.endpoint).
// Potential underscores are stripped from _port and _protocol.
func parseRequest(name, zone string) (r recordRequest, err error) {
	// 3 Possible cases:
	// 1. _port._protocol.service.namespace.pod|svc.zone
	// 2. (endpoint): endpoint.service.namespace.pod|svc.zone
	// 3. (service): service.namespace.pod|svc.zone

	base, _ := dnsutil.TrimZone(name, zone)
	// return NODATA for apex queries
	if base == "" || base == Svc || base == Pod {
		return r, nil
	}
	segs := dns.SplitDomainName(base)

	last := len(segs) - 1
	if last < 0 {
		return r, nil
	}
	r.podOrSvc = segs[last]
	if r.podOrSvc != Pod && r.podOrSvc != Svc {
		return r, errInvalidRequest
	}
	last--
	if last < 0 {
		return r, nil
	}

	r.namespace = segs[last]
	last--
	if last < 0 {
		return r, nil
	}

	r.service = segs[last]
	last--
	if last < 0 {
		return r, nil
	}

	// Because of ambiguity we check the labels left: 1: an endpoint. 2: port and protocol.
	// Anything else is a query that is too long to answer and can safely be delegated to return an nxdomain.
	switch last {
	case 0: // endpoint only
		r.endpoint = segs[last]
	case 1: // service and port
		r.protocol = stripUnderscore(segs[last])
		r.port = stripUnderscore(segs[last-1])

	default: // too long
		return r, errInvalidRequest
	}

	return r, nil
}

// stripUnderscore removes a prefixed underscore from s.
func stripUnderscore(s string) string {
	if len(s) == 0 {
		return s
	}
	if s[0] != '_' {
		return s
	}
	return s[1:]
}

// String returns a string representation of r, it just returns all fields concatenated with dots.
// This is mostly used in tests.
func (r recordRequest) String() string {
	s := r.port
	s += "." + r.protocol
	s += "." + r.endpoint
	s += "." + r.service
	s += "." + r.namespace
	s += "." + r.podOrSvc
	return s
}
'release/0.18'>release/0.18 Unnamed repository; edit this file 'description' to name the repository.
aboutsummaryrefslogtreecommitdiff
path: root/scripts/stats (unfollow)
AgeCommit message (Expand)AuthorFilesLines
2021-11-19Fix blog example (#1910)Gravatar Matthew Phillips 1-1/+1
2021-11-19Version Packages (next) (#1907)astro@0.21.0-next.10Gravatar github-actions[bot] 23-21/+28
2021-11-19Remove further dependence on vite package (#1906)Gravatar Matthew Phillips 3-5/+9
2021-11-19Version Packages (next) (#1904)astro@0.21.0-next.9Gravatar github-actions[bot] 23-21/+30
2021-11-19Remove OSX \x00 workaround (#1901)Gravatar Matthew Phillips 2-5/+5
2021-11-19Resolve vite client modules to vendored vite (#1903)Gravatar Matthew Phillips 2-2/+7
2021-11-19[ci] yarn formatGravatar matthewp 1-3/+3
2021-11-19Add Debug tests (#1882)Gravatar Matthew Phillips 4-0/+62
2021-11-19[ci] collect statsGravatar FredKSchott 1-0/+1
2021-11-19Version Packages (next) (#1881)astro@0.21.0-next.8@astrojs/renderer-vue@0.2.0-next.2Gravatar github-actions[bot] 25-23/+42
2021-11-18Improve HMR (#1896)Gravatar Drew Powers 2-10/+18
2021-11-18update depsGravatar Fred K. Schott 5-352/+65
2021-11-18fix #1778Gravatar Fred K. Schott 2-1/+8
2021-11-18Update compiler (#1869)Gravatar Nate Moore 3-11/+6
2021-11-18remove unused remark dependency (#1894)Gravatar Fred K. Schott 2-245/+13
2021-11-18Improve error messages (#1875)Gravatar Drew Powers 39-61/+448
2021-11-18pin astro compiler to older versionGravatar Fred K. Schott 2-5/+5
2021-11-18Update yarn.lock to reflect the state of the package.json files (#1892)Gravatar Jonathan Neal 5-1300/+1000
2021-11-19[ci] yarn formatGravatar FredKSchott 1-5/+3