remove wildcard query functionality (#5019)

Signed-off-by: Chris O'Haver <cohaver@infoblox.com>

plugin/kubernetes/README.md

@@ -196,27 +196,6 @@ packet received by CoreDNS must be the IP address of the Pod that sent the reque
         }
     }
 
-## Wildcards
-
-**NOTE: Wildcard queries are deprecated** and will no longer be supported in the next minor release.
-
-Some query labels accept a wildcard value to match any value.  If a label is a valid wildcard (\*,
-or the word "any"), then that label will match all values.  The labels that accept wildcards are:
-
- * _endpoint_ in an `A` record request: _endpoint_.service.namespace.svc.zone, e.g., `*.nginx.ns.svc.cluster.local`
- * _service_ in an `A` record request: _service_.namespace.svc.zone, e.g., `*.ns.svc.cluster.local`
- * _namespace_ in an `A` record request: service._namespace_.svc.zone, e.g., `nginx.*.svc.cluster.local`
- * _port and/or protocol_ in an `SRV` request: __port_.__protocol_.service.namespace.svc.zone.,
-   e.g., `_http.*.service.ns.svc.cluster.local`
- * multiple wildcards are allowed in a single query, e.g., `A` Request `*.*.svc.zone.` or `SRV` request `*.*.*.*.svc.zone.`
-
- For example, wildcards can be used to resolve all Endpoints for a Service as `A` records. e.g.: `*.service.ns.svc.myzone.local` will return the Endpoint IPs in the Service `service` in namespace `default`:
-
-```
-*.service.default.svc.cluster.local. 5	IN A	192.168.10.10
-*.service.default.svc.cluster.local. 5	IN A	192.168.25.15
-```
-
 ## Metadata
 
 The kubernetes plugin will publish the following metadata, if the *metadata*

plugin/kubernetes/external.go

@@ -24,11 +24,7 @@ func (k *Kubernetes) External(state request.Request) ([]msg.Service, int) {
 	// We are dealing with a fairly normal domain name here, but we still need to have the service
 	// and the namespace:
 	// service.namespace.<base>
-	//
-	// for service (and SRV) you can also say _tcp, and port (i.e. _http), we need those be picked
-	// up, unless they are not specified, then we use an internal wildcard.
-	port := "*"
-	protocol := "*"
+	var port, protocol string
 	namespace := segs[last]
 	if !k.namespaceExposed(namespace) {
 		return nil, dns.RcodeNameError
@@ -69,7 +65,7 @@ func (k *Kubernetes) External(state request.Request) ([]msg.Service, int) {
 
 		for _, ip := range svc.ExternalIPs {
 			for _, p := range svc.Ports {
-				if !(match(port, p.Name) && match(protocol, string(p.Protocol))) {
+				if !(matchPortAndProtocol(port, p.Name, protocol, string(p.Protocol))) {
 					continue
 				}
 				rcode = dns.RcodeSuccess

plugin/kubernetes/external_test.go

@@ -31,9 +31,6 @@ var extCases = []struct {
 			{Host: "1:2::5", Port: 80, TTL: 5, Key: "/c/org/example/testns/svc1"},
 		},
 	},
-	{
-		Qname: "*._not-udp-or-tcp.svc1.testns.example.com.", Rcode: dns.RcodeSuccess,
-	},
 	{
 		Qname: "_http._tcp.svc1.testns.example.com.", Rcode: dns.RcodeSuccess,
 		Msg: []msg.Service{

plugin/kubernetes/handler_test.go

@@ -30,14 +30,6 @@ var dnsTestCases = []test.Case{
 			test.A("svcempty.testns.svc.cluster.local.	5	IN	A	10.0.0.1"),
 		},
 	},
-	// A Service (wildcard)
-	{
-		Qname: "svc1.*.svc.cluster.local.", Qtype: dns.TypeA,
-		Rcode: dns.RcodeSuccess,
-		Answer: []dns.RR{
-			test.A("svc1.*.svc.cluster.local.  5       IN      A       10.0.0.1"),
-		},
-	},
 	{
 		Qname: "svc1.testns.svc.cluster.local.", Qtype: dns.TypeSRV,
 		Rcode: dns.RcodeSuccess,
@@ -56,42 +48,6 @@ var dnsTestCases = []test.Case{
 		Answer: []dns.RR{test.SRV("svc6.testns.svc.cluster.local.	5	IN	SRV	0 100 80 svc6.testns.svc.cluster.local.")},
 		Extra: []dns.RR{test.AAAA("svc6.testns.svc.cluster.local.  5       IN      AAAA       1234:abcd::1")},
 	},
-	// SRV Service (wildcard)
-	{
-		Qname: "svc1.*.svc.cluster.local.", Qtype: dns.TypeSRV,
-		Rcode: dns.RcodeSuccess,
-		Answer: []dns.RR{test.SRV("svc1.*.svc.cluster.local.	5	IN	SRV	0 100 80 svc1.testns.svc.cluster.local.")},
-		Extra: []dns.RR{test.A("svc1.testns.svc.cluster.local.  5       IN      A       10.0.0.1")},
-	},
-	{
-		Qname: "svcempty.*.svc.cluster.local.", Qtype: dns.TypeSRV,
-		Rcode: dns.RcodeSuccess,
-		Answer: []dns.RR{test.SRV("svcempty.*.svc.cluster.local.	5	IN	SRV	0 100 80 svcempty.testns.svc.cluster.local.")},
-		Extra: []dns.RR{test.A("svcempty.testns.svc.cluster.local.  5       IN      A       10.0.0.1")},
-	},
-	// SRV Service (wildcards)
-	{
-		Qname: "*.any.svc1.*.svc.cluster.local.", Qtype: dns.TypeSRV,
-		Rcode: dns.RcodeSuccess,
-		Answer: []dns.RR{test.SRV("*.any.svc1.*.svc.cluster.local.	5	IN	SRV	0 100 80 svc1.testns.svc.cluster.local.")},
-		Extra: []dns.RR{test.A("svc1.testns.svc.cluster.local.  5       IN      A       10.0.0.1")},
-	},
-	// A Service (wildcards)
-	{
-		Qname: "*.any.svc1.*.svc.cluster.local.", Qtype: dns.TypeA,
-		Rcode: dns.RcodeSuccess,
-		Answer: []dns.RR{
-			test.A("*.any.svc1.*.svc.cluster.local.  5       IN      A       10.0.0.1"),
-		},
-	},
-	// SRV Service Not udp/tcp
-	{
-		Qname: "*._not-udp-or-tcp.svc1.testns.svc.cluster.local.", Qtype: dns.TypeSRV,
-		Rcode: dns.RcodeNameError,
-		Ns: []dns.RR{
-			test.SOA("cluster.local.	5	IN	SOA	ns.dns.cluster.local. hostmaster.cluster.local. 1499347823 7200 1800 86400 5"),
-		},
-	},
 	// SRV Service
 	{
 		Qname: "_http._tcp.svc1.testns.svc.cluster.local.", Qtype: dns.TypeSRV,
@@ -195,14 +151,6 @@ var dnsTestCases = []test.Case{
 			test.A("hdls1.testns.svc.cluster.local.	5	IN	A	172.0.0.5"),
 		},
 	},
-	// SRV Service (Headless and portless)
-	{
-		Qname: "*.*.hdlsprtls.testns.svc.cluster.local.", Qtype: dns.TypeSRV,
-		Rcode: dns.RcodeSuccess,
-		Ns: []dns.RR{
-			test.SOA("cluster.local.	5	IN	SOA	ns.dns.cluster.local. hostmaster.cluster.local. 1499347823 7200 1800 86400 5"),
-		},
-	},
 	// AAAA
 	{
 		Qname: "5678-abcd--2.hdls1.testns.svc.cluster.local", Qtype: dns.TypeAAAA,
@@ -406,7 +354,6 @@ var dnsTestCases = []test.Case{
 }
 
 func TestServeDNS(t *testing.T) {
-
 	k := New([]string{"cluster.local."})
 	k.APIConn = &APIConnServeTest{}
 	k.Next = test.NextHandler(dns.RcodeSuccess, nil)
@@ -434,11 +381,11 @@ func TestServeDNS(t *testing.T) {
 
 		// Before sorting, make sure that CNAMES do not appear after their target records
 		if err := test.CNAMEOrder(resp); err != nil {
-			t.Error(err)
+			t.Errorf("Test %d, %v",i, err)
 		}
 
 		if err := test.SortAndCheck(resp, tc); err != nil {
-			t.Error(err)
+			t.Errorf("Test %d, %v",i, err)
 		}
 	}
 }

plugin/kubernetes/kubernetes.go

@@ -360,7 +360,7 @@ func (k *Kubernetes) Records(ctx context.Context, state request.Request, exact b
 		return nil, errNoItems
 	}
 
-	if !wildcard(r.namespace) && !k.namespaceExposed(r.namespace) {
+	if !k.namespaceExposed(r.namespace) {
 		return nil, errNsNotExposed
 	}
 
@@ -395,7 +395,7 @@ func (k *Kubernetes) findPods(r recordRequest, zone string) (pods []msg.Service,
 	}
 
 	namespace := r.namespace
-	if !wildcard(namespace) && !k.namespaceExposed(namespace) {
+	if !k.namespaceExposed(namespace) {
 		return nil, errNoItems
 	}
 
@@ -403,7 +403,7 @@ func (k *Kubernetes) findPods(r recordRequest, zone string) (pods []msg.Service,
 
 	// handle empty pod name
 	if podname == "" {
-		if k.namespaceExposed(namespace) || wildcard(namespace) {
+		if k.namespaceExposed(namespace) {
 			// NODATA
 			return nil, nil
 		}
@@ -420,7 +420,7 @@ func (k *Kubernetes) findPods(r recordRequest, zone string) (pods []msg.Service,
 	}
 
 	if k.podMode == podModeInsecure {
-		if !wildcard(namespace) && !k.namespaceExposed(namespace) { // no wildcard, but namespace does not exist
+		if !k.namespaceExposed(namespace) { // namespace does not exist
 			return nil, errNoItems
 		}
 
@@ -434,19 +434,8 @@ func (k *Kubernetes) findPods(r recordRequest, zone string) (pods []msg.Service,
 
 	// PodModeVerified
 	err = errNoItems
-	if wildcard(podname) && !wildcard(namespace) {
-		// If namespace exists, err should be nil, so that we return NODATA instead of NXDOMAIN
-		if k.namespaceExposed(namespace) {
-			err = nil
-		}
-	}
 
 	for _, p := range k.APIConn.PodIndex(ip) {
-		// If namespace has a wildcard, filter results against Corefile namespace list.
-		if wildcard(namespace) && !k.namespaceExposed(p.Namespace) {
-			continue
-		}
-
 		// check for matching ip and namespace
 		if ip == p.PodIP && match(namespace, p.Namespace) {
 			s := msg.Service{Key: strings.Join([]string{zonePath, Pod, namespace, podname}, "/"), Host: ip, TTL: k.ttl}
@@ -460,13 +449,13 @@ func (k *Kubernetes) findPods(r recordRequest, zone string) (pods []msg.Service,
 
 // findServices returns the services matching r from the cache.
 func (k *Kubernetes) findServices(r recordRequest, zone string) (services []msg.Service, err error) {
-	if !wildcard(r.namespace) && !k.namespaceExposed(r.namespace) {
+	if !k.namespaceExposed(r.namespace) {
 		return nil, errNoItems
 	}
 
 	// handle empty service name
 	if r.service == "" {
-		if k.namespaceExposed(r.namespace) || wildcard(r.namespace) {
+		if k.namespaceExposed(r.namespace) {
 			// NODATA
 			return nil, nil
 		}
@@ -475,12 +464,6 @@ func (k *Kubernetes) findServices(r recordRequest, zone string) (services []msg.
 	}
 
 	err = errNoItems
-	if wildcard(r.service) && !wildcard(r.namespace) {
-		// If namespace exists, err should be nil, so that we return NODATA instead of NXDOMAIN
-		if k.namespaceExposed(r.namespace) {
-			err = nil
-		}
-	}
 
 	var (
 		endpointsListFunc func() []*object.Endpoints
@@ -488,14 +471,11 @@ func (k *Kubernetes) findServices(r recordRequest, zone string) (services []msg.
 		serviceList       []*object.Service
 	)
 
-	if wildcard(r.service) || wildcard(r.namespace) {
-		serviceList = k.APIConn.ServiceList()
-		endpointsListFunc = func() []*object.Endpoints { return k.APIConn.EndpointsList() }
-	} else {
-		idx := object.ServiceKey(r.service, r.namespace)
-		serviceList = k.APIConn.SvcIndex(idx)
-		endpointsListFunc = func() []*object.Endpoints { return k.APIConn.EpIndex(idx) }
-	}
+
+	idx := object.ServiceKey(r.service, r.namespace)
+	serviceList = k.APIConn.SvcIndex(idx)
+	endpointsListFunc = func() []*object.Endpoints { return k.APIConn.EpIndex(idx) }
+
 
 	zonePath := msg.Path(zone, coredns)
 	for _, svc := range serviceList {
@@ -503,12 +483,6 @@ func (k *Kubernetes) findServices(r recordRequest, zone string) (services []msg.
 			continue
 		}
 
-		// If request namespace is a wildcard, filter results against Corefile namespace list.
-		// (Namespaces without a wildcard were filtered before the call to this function.)
-		if wildcard(r.namespace) && !k.namespaceExposed(svc.Namespace) {
-			continue
-		}
-
 		// If "ignore empty_service" option is set and no endpoints exist, return NXDOMAIN unless
 		// it's a headless or externalName service (covered below).
 		if k.opts.ignoreEmptyService && svc.Type != api.ServiceTypeExternalName && !svc.Headless() { // serve NXDOMAIN if no endpoint is able to answer
@@ -558,7 +532,7 @@ func (k *Kubernetes) findServices(r recordRequest, zone string) (services []msg.
 						}
 
 						for _, p := range eps.Ports {
-							if !(match(r.port, p.Name) && match(r.protocol, p.Protocol)) {
+							if !(matchPortAndProtocol(r.port, p.Name, r.protocol, p.Protocol)) {
 								continue
 							}
 							s := msg.Service{Host: addr.IP, Port: int(p.Port), TTL: k.ttl}
@@ -576,7 +550,7 @@ func (k *Kubernetes) findServices(r recordRequest, zone string) (services []msg.
 
 		// ClusterIP service
 		for _, p := range svc.Ports {
-			if !(match(r.port, p.Name) && match(r.protocol, string(p.Protocol))) {
+			if !(matchPortAndProtocol(r.port, p.Name, r.protocol, string(p.Protocol))) {
 				continue
 			}
 
@@ -598,20 +572,14 @@ func (k *Kubernetes) Serial(state request.Request) uint32 { return uint32(k.APIC
 // MinTTL returns the minimal TTL.
 func (k *Kubernetes) MinTTL(state request.Request) uint32 { return k.ttl }
 
-// match checks if a and b are equal taking wildcards into account.
+// match checks if a and b are equal.
 func match(a, b string) bool {
-	if wildcard(a) {
-		return true
-	}
-	if wildcard(b) {
-		return true
-	}
 	return strings.EqualFold(a, b)
 }
 
-// wildcard checks whether s contains a wildcard value defined as "*" or "any".
-func wildcard(s string) bool {
-	return s == "*" || s == "any"
+// matchPortAndProtocol matches port and protocol, permitting the the 'a' inputs to be wild
+func matchPortAndProtocol(aPort, bPort, aProtocol, bProtocol string) bool {
+	return (match(aPort, bPort) || aPort == "") && (match(aProtocol, bProtocol) || aProtocol == "")
 }
 
 const coredns = "c" // used as a fake key prefix in msg.Service

plugin/kubernetes/kubernetes_test.go

@@ -14,27 +14,6 @@ import (
 	meta "k8s.io/apimachinery/pkg/apis/meta/v1"
 )
 
-func TestWildcard(t *testing.T) {
-	var tests = []struct {
-		s        string
-		expected bool
-	}{
-		{"mynamespace", false},
-		{"*", true},
-		{"any", true},
-		{"my*space", false},
-		{"*space", false},
-		{"myname*", false},
-	}
-
-	for _, te := range tests {
-		got := wildcard(te.s)
-		if got != te.expected {
-			t.Errorf("Expected Wildcard result '%v' for example '%v', got '%v'.", te.expected, te.s, got)
-		}
-	}
-}
-
 func TestEndpointHostname(t *testing.T) {
 	var tests = []struct {
 		ip               string

plugin/kubernetes/metadata_test.go

@@ -29,8 +29,8 @@ var metadataCases = []struct {
 			"kubernetes/endpoint":  "",
 			"kubernetes/kind":      "pod",
 			"kubernetes/namespace": "podns",
-			"kubernetes/port-name": "*",
-			"kubernetes/protocol":  "*",
+			"kubernetes/port-name": "",
+			"kubernetes/protocol":  "",
 			"kubernetes/service":   "10-240-0-1",
 		},
 	},
@@ -40,8 +40,8 @@ var metadataCases = []struct {
 			"kubernetes/endpoint":  "",
 			"kubernetes/kind":      "svc",
 			"kubernetes/namespace": "ns",
-			"kubernetes/port-name": "*",
-			"kubernetes/protocol":  "*",
+			"kubernetes/port-name": "",
+			"kubernetes/protocol":  "",
 			"kubernetes/service":   "s",
 		},
 	},
@@ -52,8 +52,8 @@ var metadataCases = []struct {
 			"kubernetes/endpoint":  "",
 			"kubernetes/kind":      "svc",
 			"kubernetes/namespace": "ns",
-			"kubernetes/port-name": "*",
-			"kubernetes/protocol":  "*",
+			"kubernetes/port-name": "",
+			"kubernetes/protocol":  "",
 			"kubernetes/service":   "s",
 		},
 	},
@@ -76,8 +76,8 @@ var metadataCases = []struct {
 			"kubernetes/endpoint":  "ep",
 			"kubernetes/kind":      "svc",
 			"kubernetes/namespace": "ns",
-			"kubernetes/port-name": "*",
-			"kubernetes/protocol":  "*",
+			"kubernetes/port-name": "",
+			"kubernetes/protocol":  "",
 			"kubernetes/service":   "s",
 		},
 	},

plugin/kubernetes/parse.go

@@ -38,18 +38,6 @@ func parseRequest(name, zone string) (r recordRequest, err error) {
 	}
 	segs := dns.SplitDomainName(base)
 
-	r.port = "*"
-	r.protocol = "*"
-	// for r.name, r.namespace and r.endpoint, we need to know if they have been set or not...
-	// For endpoint: if empty we should skip the endpoint check in k.get(). Hence we cannot set if to "*".
-	// For name: myns.svc.cluster.local != *.myns.svc.cluster.local
-	// For namespace: svc.cluster.local != *.svc.cluster.local
-
-	// start at the right and fill out recordRequest with the bits we find, so we look for
-	// pod|svc.namespace.service and then either
-	// * endpoint
-	// *_protocol._port
-
 	last := len(segs) - 1
 	if last < 0 {
 		return r, nil

plugin/kubernetes/parse_test.go

@@ -15,10 +15,8 @@ func TestParseRequest(t *testing.T) {
 	}{
 		// valid SRV request
 		{"_http._tcp.webs.mynamespace.svc.inter.webs.tests.", "http.tcp..webs.mynamespace.svc"},
-		// wildcard acceptance
-		{"*.any.*.any.svc.inter.webs.tests.", "*.any..*.any.svc"},
 		// A request of endpoint
-		{"1-2-3-4.webs.mynamespace.svc.inter.webs.tests.", "*.*.1-2-3-4.webs.mynamespace.svc"},
+		{"1-2-3-4.webs.mynamespace.svc.inter.webs.tests.", "..1-2-3-4.webs.mynamespace.svc"},
 		// bare zone
 		{"inter.webs.tests.", "....."},
 		// bare svc type