dont require/allow "_" prefix for srv wildcard fields (#472)

* dont require/allow "_" prefix for srv wildcard fields

* streamline parse/validation of req name

* removing nametemplate

* error when zone not found, loopify unit tests
This commit is contained in:
Chris O'Haver 2017-01-15 03:12:28 -05:00 committed by Miek Gieben
parent b6a2a5aeaa
commit a6d232a622
9 changed files with 245 additions and 600 deletions

View file

@ -1,15 +1,14 @@
# kubernetes # kubernetes
*kubernetes* enables reading zone data from a kubernetes cluster. Record names *kubernetes* enables reading zone data from a kubernetes cluster. Record names
are constructed as "myservice.mynamespace.coredns.local" where: are constructed as "myservice.mynamespace.type.coredns.local" where:
* "myservice" is the name of the k8s service (this may include multiple DNS labels, * "myservice" is the name of the k8s service (this may include multiple DNS labels,
such as "c1.myservice"), such as "c1.myservice"),
* "mynamespace" is the k8s namespace for the service, and * "mynamespace" is the k8s namespace for the service, and
* "type" is svc or pod
* "coredns.local" is the zone configured for `kubernetes`. * "coredns.local" is the zone configured for `kubernetes`.
The record name format can be changed by specifying a name template in the Corefile.
## Syntax ## Syntax
~~~ ~~~
@ -50,9 +49,6 @@ This is the default kubernetes setup, with everything specified in full:
# The tls cert, key and the CA cert filenames # The tls cert, key and the CA cert filenames
tls cert key cacert tls cert key cacert
# Assemble k8s record names with the template
template {service}.{namespace}.{type}.{zone}
# Only expose the k8s namespace "demo" # Only expose the k8s namespace "demo"
namespaces demo namespaces demo
@ -82,22 +78,12 @@ This is the default kubernetes setup, with everything specified in full:
Defaults: Defaults:
* If the `namespaces` keyword is omitted, all kubernetes namespaces are exposed. * If the `namespaces` keyword is omitted, all kubernetes namespaces are exposed.
* If the `template` keyword is omitted, the default template of "{service}.{namespace}.{type}.{zone}" is used.
* If the `resyncperiod` keyword is omitted, the default resync period is 5 minutes. * If the `resyncperiod` keyword is omitted, the default resync period is 5 minutes.
* The `labels` keyword is only used when filtering results based on kubernetes label selector syntax * The `labels` keyword is only used when filtering results based on kubernetes label selector syntax
is required. The label selector syntax is described in the kubernetes API documentation at: is required. The label selector syntax is described in the kubernetes API documentation at:
http://kubernetes.io/docs/user-guide/labels/ http://kubernetes.io/docs/user-guide/labels/
* If the `pods` keyword is omitted, all pod type requests will result in NXDOMAIN * If the `pods` keyword is omitted, all pod type requests will result in NXDOMAIN
### Template Syntax
Record name templates can be constructed using the symbolic elements:
| template symbol | description |
| `{service}` | Kubernetes object/service name. |
| `{namespace}` | The kubernetes namespace. |
| `{type}` | The type of the kubernetes object. Supports values 'svc' and 'pod'. |
| `{zone}` | The zone configured for the kubernetes middleware. |
### Basic Setup ### Basic Setup
#### Launch Kubernetes #### Launch Kubernetes
@ -146,7 +132,6 @@ Build CoreDNS and launch using this configuration file:
kubernetes coredns.local { kubernetes coredns.local {
resyncperiod 5m resyncperiod 5m
endpoint http://localhost:8080 endpoint http://localhost:8080
template {service}.{namespace}.{type}.{zone}
namespaces demo namespaces demo
# Only expose the records for kubernetes objects # Only expose the records for kubernetes objects
# that matches this label selector. # that matches this label selector.

View file

@ -10,7 +10,6 @@ import (
"github.com/miekg/coredns/middleware" "github.com/miekg/coredns/middleware"
"github.com/miekg/coredns/middleware/etcd/msg" "github.com/miekg/coredns/middleware/etcd/msg"
"github.com/miekg/coredns/middleware/kubernetes/nametemplate"
"github.com/miekg/coredns/middleware/pkg/dnsutil" "github.com/miekg/coredns/middleware/pkg/dnsutil"
dnsstrings "github.com/miekg/coredns/middleware/pkg/strings" dnsstrings "github.com/miekg/coredns/middleware/pkg/strings"
"github.com/miekg/coredns/middleware/proxy" "github.com/miekg/coredns/middleware/proxy"
@ -38,7 +37,6 @@ type Kubernetes struct {
APIClientKey string APIClientKey string
APIConn *dnsController APIConn *dnsController
ResyncPeriod time.Duration ResyncPeriod time.Duration
NameTemplate *nametemplate.Template
Namespaces []string Namespaces []string
LabelSelector *unversionedapi.LabelSelector LabelSelector *unversionedapi.LabelSelector
Selector *labels.Selector Selector *labels.Selector
@ -69,16 +67,22 @@ type pod struct {
addr string addr string
} }
type recordRequest struct {
port, protocol, endpoint, service, namespace, typeName, zone string
}
var errNoItems = errors.New("no items found") var errNoItems = errors.New("no items found")
var errNsNotExposed = errors.New("namespace is not exposed") var errNsNotExposed = errors.New("namespace is not exposed")
var errInvalidRequest = errors.New("invalid query name") var errInvalidRequest = errors.New("invalid query name")
// Services implements the ServiceBackend interface. // Services implements the ServiceBackend interface.
func (k *Kubernetes) Services(state request.Request, exact bool, opt middleware.Options) ([]msg.Service, []msg.Service, error) { func (k *Kubernetes) Services(state request.Request, exact bool, opt middleware.Options) ([]msg.Service, []msg.Service, error) {
if state.Type() == "SRV" && !ValidSRV(state.Name()) {
return nil, nil, errInvalidRequest r, e := k.parseRequest(state.Name(), state.Type())
if e != nil {
return nil, nil, e
} }
s, e := k.Records(state.Name(), exact) s, e := k.Records(r)
return s, nil, e // Haven't implemented debug queries yet. return s, nil, e // Haven't implemented debug queries yet.
} }
@ -177,85 +181,94 @@ func (k *Kubernetes) InitKubeCache() error {
return err return err
} }
// getZoneForName returns the zone string that matches the name and a func (k *Kubernetes) parseRequest(lowerCasedName, qtype string) (r recordRequest, err error) {
// list of the DNS labels from name that are within the zone. // 3 Possible cases
// For example, if "coredns.local" is a zone configured for the // SRV Request: _port._protocol.service.namespace.type.zone
// Kubernetes middleware, then getZoneForName("a.b.coredns.local") // A Request (endpoint): endpoint.service.namespace.type.zone
// will return ("coredns.local", ["a", "b"]). // A Request (service): service.namespace.type.zone
func (k *Kubernetes) getZoneForName(name string) (string, []string) {
var zone string
var serviceSegments []string
// separate zone from rest of lowerCasedName
var segs []string
for _, z := range k.Zones { for _, z := range k.Zones {
if dns.IsSubDomain(z, name) { if dns.IsSubDomain(z, lowerCasedName) {
zone = z r.zone = z
serviceSegments = dns.SplitDomainName(name) segs = dns.SplitDomainName(lowerCasedName)
serviceSegments = serviceSegments[:len(serviceSegments)-dns.CountLabel(zone)] segs = segs[:len(segs)-dns.CountLabel(r.zone)]
break break
} }
} }
if r.zone == "" {
return zone, serviceSegments return r, errors.New("zone not found")
} }
// stripSRVPrefix separates out the port and protocol segments, if present offset := 0
// If not present, assume all ports/protocols (e.g. wildcard) if len(segs) == 5 {
func stripSRVPrefix(name []string) (string, string, []string) { // This is a SRV style request, get first two elements as port and
if name[0][0] == '_' && name[1][0] == '_' { // protocol, stripping leading underscores if present.
return name[0][1:], name[1][1:], name[2:] if segs[0][0] == '_' {
r.port = segs[0][1:]
} else {
r.port = segs[0]
if !symbolContainsWildcard(r.port) {
return r, errors.New("srv port must start with an underscore or be a wildcard")
} }
// no srv prefix present }
return "*", "*", name if segs[1][0] == '_' {
r.protocol = segs[1][1:]
if r.protocol != "tcp" && r.protocol != "udp" {
return r, errors.New("invalid srv protocol: " + r.protocol)
}
} else {
r.protocol = segs[1]
if !symbolContainsWildcard(r.protocol) {
return r, errors.New("srv protocol must start with an underscore or be a wildcard")
}
}
offset = 2
} else if len(segs) == 4 {
// This is an endpoint A style request. Get first element as endpoint.
r.endpoint = segs[0]
offset = 1
} }
func stripEndpointName(name []string) (endpoint string, nameOut []string) { // SRV requests require a port and protocol
if len(name) == 4 { if qtype == "SRV" {
return strings.ToLower(name[0]), name[1:] if r.port == "" || r.protocol == "" {
return r, errors.New("invalid srv request")
} }
return "", name }
// A requests cannot have port/protocol
if qtype == "A" {
if r.port != "" && r.protocol != "" {
return r, errors.New("invalid a request")
}
}
if len(segs) == (offset + 3) {
r.service = segs[offset]
r.namespace = segs[offset+1]
r.typeName = segs[offset+2]
return r, nil
}
return r, errors.New("invalid request")
} }
// Records looks up services in kubernetes. If exact is true, it will lookup // Records looks up services in kubernetes. If exact is true, it will lookup
// just this name. This is used when find matches when completing SRV lookups // just this name. This is used when find matches when completing SRV lookups
// for instance. // for instance.
func (k *Kubernetes) Records(name string, exact bool) ([]msg.Service, error) { func (k *Kubernetes) Records(r recordRequest) ([]msg.Service, error) {
var (
serviceName string
namespace string
typeName string
)
zone, serviceSegments := k.getZoneForName(name)
port, protocol, serviceSegments := stripSRVPrefix(serviceSegments)
endpointname, serviceSegments := stripEndpointName(serviceSegments)
if len(serviceSegments) < 3 {
return nil, errNoItems
}
serviceName = serviceSegments[0]
namespace = serviceSegments[1]
typeName = serviceSegments[2]
if namespace == "" {
err := errors.New("Parsing query string did not produce a namespace value. Assuming wildcard namespace.")
log.Printf("[WARN] %v\n", err)
namespace = "*"
}
if serviceName == "" {
err := errors.New("Parsing query string did not produce a serviceName value. Assuming wildcard serviceName.")
log.Printf("[WARN] %v\n", err)
serviceName = "*"
}
// Abort if the namespace does not contain a wildcard, and namespace is not published per CoreFile // Abort if the namespace does not contain a wildcard, and namespace is not published per CoreFile
// Case where namespace contains a wildcard is handled in Get(...) method. // Case where namespace contains a wildcard is handled in Get(...) method.
if (!symbolContainsWildcard(namespace)) && (len(k.Namespaces) > 0) && (!dnsstrings.StringInSlice(namespace, k.Namespaces)) { if (!symbolContainsWildcard(r.namespace)) && (len(k.Namespaces) > 0) && (!dnsstrings.StringInSlice(r.namespace, k.Namespaces)) {
return nil, errNsNotExposed return nil, errNsNotExposed
} }
services, pods, err := k.Get(namespace, serviceName, endpointname, port, protocol, typeName) services, pods, err := k.Get(r)
if err != nil { if err != nil {
return nil, err return nil, err
} }
@ -264,7 +277,7 @@ func (k *Kubernetes) Records(name string, exact bool) ([]msg.Service, error) {
return nil, errNoItems return nil, errNoItems
} }
records := k.getRecordsForK8sItems(services, pods, zone) records := k.getRecordsForK8sItems(services, pods, r.zone)
return records, nil return records, nil
} }
@ -320,18 +333,6 @@ func (k *Kubernetes) getRecordsForK8sItems(services []service, pods []pod, zone
return records return records
} }
// Get retrieves matching data from the cache.
func (k *Kubernetes) Get(namespace, servicename, endpointname, port, protocol, typeName string) (services []service, pods []pod, err error) {
switch {
case typeName == "pod":
pods, err = k.findPods(namespace, servicename)
return nil, pods, err
default:
services, err = k.findServices(namespace, servicename, endpointname, port, protocol)
return services, nil, err
}
}
func ipFromPodName(podname string) string { func ipFromPodName(podname string) string {
if strings.Count(podname, "-") == 3 && !strings.Contains(podname, "--") { if strings.Count(podname, "-") == 3 && !strings.Contains(podname, "--") {
return strings.Replace(podname, "-", ".", -1) return strings.Replace(podname, "-", ".", -1)
@ -362,18 +363,30 @@ func (k *Kubernetes) findPods(namespace, podname string) (pods []pod, err error)
} }
func (k *Kubernetes) findServices(namespace, servicename, endpointname, port, protocol string) ([]service, error) { // Get retrieves matching data from the cache.
func (k *Kubernetes) Get(r recordRequest) (services []service, pods []pod, err error) {
switch {
case r.typeName == "pod":
pods, err = k.findPods(r.namespace, r.service)
return nil, pods, err
default:
services, err = k.findServices(r)
return services, nil, err
}
}
func (k *Kubernetes) findServices(r recordRequest) ([]service, error) {
serviceList := k.APIConn.ServiceList() serviceList := k.APIConn.ServiceList()
var resultItems []service var resultItems []service
nsWildcard := symbolContainsWildcard(namespace) nsWildcard := symbolContainsWildcard(r.namespace)
serviceWildcard := symbolContainsWildcard(servicename) serviceWildcard := symbolContainsWildcard(r.service)
portWildcard := symbolContainsWildcard(port) portWildcard := symbolContainsWildcard(r.port) || r.port == ""
protocolWildcard := symbolContainsWildcard(protocol) protocolWildcard := symbolContainsWildcard(r.protocol) || r.protocol == ""
for _, svc := range serviceList { for _, svc := range serviceList {
if !(symbolMatches(namespace, svc.Namespace, nsWildcard) && symbolMatches(servicename, svc.Name, serviceWildcard)) { if !(symbolMatches(r.namespace, svc.Namespace, nsWildcard) && symbolMatches(r.service, svc.Name, serviceWildcard)) {
continue continue
} }
// If namespace has a wildcard, filter results against Corefile namespace list. // If namespace has a wildcard, filter results against Corefile namespace list.
@ -384,7 +397,7 @@ func (k *Kubernetes) findServices(namespace, servicename, endpointname, port, pr
s := service{name: svc.Name, namespace: svc.Namespace, addr: svc.Spec.ClusterIP} s := service{name: svc.Name, namespace: svc.Namespace, addr: svc.Spec.ClusterIP}
if s.addr != api.ClusterIPNone { if s.addr != api.ClusterIPNone {
for _, p := range svc.Spec.Ports { for _, p := range svc.Spec.Ports {
if !(symbolMatches(port, strings.ToLower(p.Name), portWildcard) && symbolMatches(protocol, strings.ToLower(string(p.Protocol)), protocolWildcard)) { if !(symbolMatches(r.port, strings.ToLower(p.Name), portWildcard) && symbolMatches(r.protocol, strings.ToLower(string(p.Protocol)), protocolWildcard)) {
continue continue
} }
s.ports = append(s.ports, p) s.ports = append(s.ports, p)
@ -405,10 +418,10 @@ func (k *Kubernetes) findServices(namespace, servicename, endpointname, port, pr
for _, addr := range eps.Addresses { for _, addr := range eps.Addresses {
for _, p := range eps.Ports { for _, p := range eps.Ports {
ephostname := endpointHostname(addr) ephostname := endpointHostname(addr)
if endpointname != "" && endpointname != ephostname { if r.endpoint != "" && r.endpoint != ephostname {
continue continue
} }
if !(symbolMatches(port, strings.ToLower(p.Name), portWildcard) && symbolMatches(protocol, strings.ToLower(string(p.Protocol)), protocolWildcard)) { if !(symbolMatches(r.port, strings.ToLower(p.Name), portWildcard) && symbolMatches(r.protocol, strings.ToLower(string(p.Protocol)), protocolWildcard)) {
continue continue
} }
s.endpoints = append(s.endpoints, endpoint{addr: addr, port: p}) s.endpoints = append(s.endpoints, endpoint{addr: addr, port: p})
@ -422,16 +435,10 @@ func (k *Kubernetes) findServices(namespace, servicename, endpointname, port, pr
} }
func symbolMatches(queryString, candidateString string, wildcard bool) bool { func symbolMatches(queryString, candidateString string, wildcard bool) bool {
result := false if wildcard {
switch { return true
case !wildcard:
result = (queryString == candidateString)
case queryString == "*":
result = true
case queryString == "any":
result = true
} }
return result return queryString == candidateString
} }
// getServiceRecordForIP: Gets a service record with a cluster ip matching the ip argument // getServiceRecordForIP: Gets a service record with a cluster ip matching the ip argument
@ -476,57 +483,3 @@ func (k *Kubernetes) getServiceRecordForIP(ip, name string) []msg.Service {
func symbolContainsWildcard(symbol string) bool { func symbolContainsWildcard(symbol string) bool {
return (strings.Contains(symbol, "*") || (symbol == "any")) return (strings.Contains(symbol, "*") || (symbol == "any"))
} }
// ValidSRV parses a server record validating _port._proto. prefix labels.
// The valid schema is:
// * Fist two segments must start with an "_",
// * Second segment must be one of _tcp|_udp|_*|_any
func ValidSRV(name string) bool {
// Does it start with a "_" ?
if len(name) > 0 && name[0] != '_' {
return false
}
// First label
first, end := dns.NextLabel(name, 0)
if end {
return false
}
// Second label
off, end := dns.NextLabel(name, first)
if end {
return false
}
// first:off has captured _tcp. or _udp. (if present)
second := name[first:off]
if len(second) > 0 && second[0] != '_' {
return false
}
// A bit convoluted to avoid strings.ToLower
if len(second) == 5 {
// matches _tcp
if (second[1] == 't' || second[1] == 'T') && (second[2] == 'c' || second[2] == 'C') &&
(second[3] == 'p' || second[3] == 'P') {
return true
}
// matches _udp
if (second[1] == 'u' || second[1] == 'U') && (second[2] == 'd' || second[2] == 'D') &&
(second[3] == 'p' || second[3] == 'P') {
return true
}
// matches _any
if (second[1] == 'a' || second[1] == 'A') && (second[2] == 'n' || second[2] == 'N') &&
(second[3] == 'y' || second[3] == 'Y') {
return true
}
}
// matches _*
if len(second) == 3 && second[1] == '*' {
return true
}
return false
}

View file

@ -1,6 +1,7 @@
package kubernetes package kubernetes
import "testing" import "testing"
import "reflect"
// Test data for TestSymbolContainsWildcard cases. // Test data for TestSymbolContainsWildcard cases.
var testdataSymbolContainsWildcard = []struct { var testdataSymbolContainsWildcard = []struct {
@ -23,3 +24,114 @@ func TestSymbolContainsWildcard(t *testing.T) {
} }
} }
} }
func expectString(t *testing.T, function, qtype, query string, r *recordRequest, field, expected string) {
ref := reflect.ValueOf(r)
ref_f := reflect.Indirect(ref).FieldByName(field)
got := ref_f.String()
if got != expected {
t.Errorf("Expected %v(%v, \"%v\") to get %v == \"%v\". Instead got \"%v\".", function, query, qtype, field, expected, got)
}
}
func TestParseRequest(t *testing.T) {
var tcs map[string]string
k := Kubernetes{Zones: []string{"inter.webs.test"}}
f := "parseRequest"
// Test a valid SRV request
//
query := "_http._tcp.webs.mynamespace.svc.inter.webs.test."
r, e := k.parseRequest(query, "SRV")
if e != nil {
t.Errorf("Expected no error from parseRequest(%v, \"SRV\"). Instead got '%v'.", query, e)
}
tcs = map[string]string{
"port": "http",
"protocol": "tcp",
"endpoint": "",
"service": "webs",
"namespace": "mynamespace",
"typeName": "svc",
"zone": "inter.webs.test",
}
for field, expected := range tcs {
expectString(t, f, "SRV", query, &r, field, expected)
}
// Test wildcard acceptance
//
query = "*.any.*.any.svc.inter.webs.test."
r, e = k.parseRequest(query, "SRV")
if e != nil {
t.Errorf("Expected no error from parseRequest(\"%v\", \"SRV\"). Instead got '%v'.", query, e)
}
tcs = map[string]string{
"port": "*",
"protocol": "any",
"endpoint": "",
"service": "*",
"namespace": "any",
"typeName": "svc",
"zone": "inter.webs.test",
}
for field, expected := range tcs {
expectString(t, f, "SRV", query, &r, field, expected)
}
// Test A request of endpoint
//
query = "1-2-3-4.webs.mynamespace.svc.inter.webs.test."
r, e = k.parseRequest(query, "A")
if e != nil {
t.Errorf("Expected no error from parseRequest(\"%v\", \"A\"). Instead got '%v'.", query, e)
}
tcs = map[string]string{
"port": "",
"protocol": "",
"endpoint": "1-2-3-4",
"service": "webs",
"namespace": "mynamespace",
"typeName": "svc",
"zone": "inter.webs.test",
}
for field, expected := range tcs {
expectString(t, f, "A", query, &r, field, expected)
}
// Invalid query tests
//
invalidAQueries := []string{
"_http._tcp.webs.mynamespace.svc.inter.webs.test.", // A requests cannot have port or protocol
"servname.ns1.srv.inter.nets.test.", // A requests must have zone that matches corefile
}
for _, q := range invalidAQueries {
_, e = k.parseRequest(q, "A")
if e == nil {
t.Errorf("Expected error from %v(\"%v\", \"A\").", f, q)
}
}
invalidSRVQueries := []string{
"webs.mynamespace.svc.inter.webs.test.", // SRV requests must have port and protocol
"_http._pcp.webs.mynamespace.svc.inter.webs.test.", // SRV protocol must be tcp or udp
"_http._tcp.ep.webs.ns.svc.inter.webs.test.", // SRV requests cannot have an endpoint
"_*._*.webs.mynamespace.svc.inter.webs.test.", // SRV request with invalid wildcards
"_http._tcp",
"_tcp.test.",
".",
}
for _, q := range invalidSRVQueries {
_, e = k.parseRequest(q, "SRV")
if e == nil {
t.Errorf("Expected error from %v(\"%v\", \"SRV\").", f, q)
}
}
}

View file

@ -12,7 +12,11 @@ import (
) )
func (k Kubernetes) records(state request.Request, exact bool) ([]msg.Service, error) { func (k Kubernetes) records(state request.Request, exact bool) ([]msg.Service, error) {
services, err := k.Records(state.Name(), exact) r, err := k.parseRequest(state.Name(), state.Type())
if err != nil {
return nil, err
}
services, err := k.Records(r)
if err != nil { if err != nil {
return nil, err return nil, err
} }

View file

@ -1,195 +0,0 @@
package nametemplate
import (
"errors"
"strings"
dns_strings "github.com/miekg/coredns/middleware/pkg/strings"
)
// Likely symbols that require support:
// {id}
// {ip}
// {portname}
// {protocolname}
// {servicename}
// {namespace}
// {type} "svc" or "pod"
// {zone}
// SkyDNS normal services have an A-record of the form "{servicename}.{namespace}.{type}.{zone}"
// This resolves to the cluster IP of the service.
// SkyDNS headless services have an A-record of the form "{servicename}.{namespace}.{type}.{zone}"
// This resolves to the set of IPs of the pods selected by the Service. Clients are expected to
// consume the set or else use round-robin selection from the set.
var symbols = map[string]string{
"service": "{service}",
"namespace": "{namespace}",
"type": "{type}",
"zone": "{zone}",
}
var types = []string{
"svc",
"pod",
}
var requiredSymbols = []string{
"namespace",
"service",
}
// TODO: Validate that provided NameTemplate string only contains:
// * valid, known symbols, or
// * static strings
// TODO: Support collapsing multiple segments into a symbol. Either:
// * all left-over segments are used as the "service" name, or
// * some scheme like "{namespace}.{namespace}" means use
// segments concatenated with a "." for the namespace, or
// * {namespace2:4} means use segements 2->4 for the namespace.
// TODO: possibly need to store length of segmented format to handle cases
// where query string segments to a shorter or longer list than the template.
// When query string segments to shorter than template:
// * either wildcards are being used, or
// * we are not looking up an A, AAAA, or SRV record (eg NS), or
// * we can just short-circuit failure before hitting the k8s API.
// Where the query string is longer than the template, need to define which
// symbol consumes the other segments. Most likely this would be the servicename.
// Also consider how to handle static strings in the format template.
// Template holds the kubernetes template.
type Template struct {
formatString string
splitFormat []string
// Element is a map of element name :: index in the segmented record name for the named element
Element map[string]int
}
// SetTemplate use the string s the set the template.
func (t *Template) SetTemplate(s string) error {
var err error
t.Element = map[string]int{}
t.formatString = s
t.splitFormat = strings.Split(t.formatString, ".")
for templateIndex, v := range t.splitFormat {
elementPositionSet := false
for name, symbol := range symbols {
if v == symbol {
t.Element[name] = templateIndex
elementPositionSet = true
break
}
}
if !elementPositionSet {
if strings.Contains(v, "{") {
err = errors.New("Record name template contains the unknown symbol '" + v + "'")
return err
}
}
}
if err == nil && !t.IsValid() {
err = errors.New("Record name template does not pass NameTemplate validation")
return err
}
return err
}
// TODO: Find a better way to pull the data segments out of the
// query string based on the template. Perhaps it is better
// to treat the query string segments as a reverse stack and
// step down the stack to find the right element.
// ZoneFromSegmentArray returns the zone string from the segments.
func (t *Template) ZoneFromSegmentArray(segments []string) string {
index, ok := t.Element["zone"]
if !ok {
return ""
}
return strings.Join(segments[index:], ".")
}
// NamespaceFromSegmentArray returns the namespace string from the segments.
func (t *Template) NamespaceFromSegmentArray(segments []string) string {
return t.symbolFromSegmentArray("namespace", segments)
}
// ServiceFromSegmentArray returns the service string from the segments.
func (t *Template) ServiceFromSegmentArray(segments []string) string {
return t.symbolFromSegmentArray("service", segments)
}
// TypeFromSegmentArray returns the type string from the segments.
func (t *Template) TypeFromSegmentArray(segments []string) string {
typeSegment := t.symbolFromSegmentArray("type", segments)
// Limit type to known types symbols
if dns_strings.StringInSlice(typeSegment, types) {
return ""
}
return typeSegment
}
func (t *Template) symbolFromSegmentArray(symbol string, segments []string) string {
index, ok := t.Element[symbol]
if !ok {
return ""
}
return segments[index]
}
// RecordNameFromNameValues returns the string produced by applying the
// values to the NameTemplate format string.
func (t *Template) RecordNameFromNameValues(values NameValues) string {
recordName := make([]string, len(t.splitFormat))
copy(recordName[:], t.splitFormat)
for name, index := range t.Element {
if index == -1 {
continue
}
switch name {
case "type":
recordName[index] = values.TypeName
case "service":
recordName[index] = values.ServiceName
case "namespace":
recordName[index] = values.Namespace
case "zone":
recordName[index] = values.Zone
}
}
return strings.Join(recordName, ".")
}
// IsValid returns true if the template has all the required symbols, false otherwise.
func (t *Template) IsValid() bool {
result := true
// Ensure that all requiredSymbols are found in NameTemplate
for _, symbol := range requiredSymbols {
if _, ok := t.Element[symbol]; !ok {
result = false
break
}
}
return result
}
// NameValues contains a number of values.
// TODO(...): better docs.
type NameValues struct {
ServiceName string
Namespace string
TypeName string
Zone string
}

View file

@ -1,127 +0,0 @@
package nametemplate
import (
"strings"
"testing"
)
const (
zone = 0
namespace = 1
service = 2
)
// Map of format string :: expected locations of name symbols in the format.
// -1 value indicates that symbol does not exist in format.
var exampleTemplates = map[string][]int{
"{service}.{namespace}.{type}.{zone}": {3, 1, 0}, // service symbol expected @ position 0, namespace @ 1, zone @ 3
"{namespace}.{type}.{zone}": {2, 0, -1},
"": {-1, -1, -1},
}
func TestSetTemplate(t *testing.T) {
for s, expectedValue := range exampleTemplates {
n := new(Template)
n.SetTemplate(s)
// check the indexes resulting from calling SetTemplate() against expectedValues
if expectedValue[zone] != -1 {
if n.Element["zone"] != expectedValue[zone] {
t.Errorf("Expected zone at index '%v', instead found at index '%v' for format string '%v'", expectedValue[zone], n.Element["zone"], s)
}
}
}
}
func TestServiceFromSegmentArray(t *testing.T) {
var (
n *Template
formatString string
queryString string
splitQuery []string
expectedService string
actualService string
)
// Case where template contains {service}
n = new(Template)
formatString = "{service}.{namespace}.{type}.{zone}"
n.SetTemplate(formatString)
queryString = "myservice.mynamespace.svc.coredns"
splitQuery = strings.Split(queryString, ".")
expectedService = "myservice"
actualService = n.ServiceFromSegmentArray(splitQuery)
if actualService != expectedService {
t.Errorf("Expected service name '%v', instead got service name '%v' for query string '%v' and format '%v'", expectedService, actualService, queryString, formatString)
}
// Case where template does not contain {service}
n = new(Template)
formatString = "{namespace}.{type}.{zone}"
n.SetTemplate(formatString)
queryString = "mynamespace.svc.coredns"
splitQuery = strings.Split(queryString, ".")
expectedService = ""
actualService = n.ServiceFromSegmentArray(splitQuery)
if actualService != expectedService {
t.Errorf("Expected service name '%v', instead got service name '%v' for query string '%v' and format '%v'", expectedService, actualService, queryString, formatString)
}
}
func TestZoneFromSegmentArray(t *testing.T) {
var (
n *Template
formatString string
queryString string
splitQuery []string
expectedZone string
actualZone string
)
// Case where template contains {zone}
n = new(Template)
formatString = "{service}.{namespace}.{type}.{zone}"
n.SetTemplate(formatString)
queryString = "myservice.mynamespace.svc.coredns"
splitQuery = strings.Split(queryString, ".")
expectedZone = "coredns"
actualZone = n.ZoneFromSegmentArray(splitQuery)
if actualZone != expectedZone {
t.Errorf("Expected zone name '%v', instead got zone name '%v' for query string '%v' and format '%v'", expectedZone, actualZone, queryString, formatString)
}
// Case where template does not contain {zone}
n = new(Template)
formatString = "{service}.{namespace}.{type}"
n.SetTemplate(formatString)
queryString = "mynamespace.coredns.svc"
splitQuery = strings.Split(queryString, ".")
expectedZone = ""
actualZone = n.ZoneFromSegmentArray(splitQuery)
if actualZone != expectedZone {
t.Errorf("Expected zone name '%v', instead got zone name '%v' for query string '%v' and format '%v'", expectedZone, actualZone, queryString, formatString)
}
// Case where zone is multiple segments
n = new(Template)
formatString = "{service}.{namespace}.{type}.{zone}"
n.SetTemplate(formatString)
queryString = "myservice.mynamespace.svc.coredns.cluster.local"
splitQuery = strings.Split(queryString, ".")
expectedZone = "coredns.cluster.local"
actualZone = n.ZoneFromSegmentArray(splitQuery)
if actualZone != expectedZone {
t.Errorf("Expected zone name '%v', instead got zone name '%v' for query string '%v' and format '%v'", expectedZone, actualZone, queryString, formatString)
}
}

View file

@ -8,7 +8,6 @@ import (
"github.com/miekg/coredns/core/dnsserver" "github.com/miekg/coredns/core/dnsserver"
"github.com/miekg/coredns/middleware" "github.com/miekg/coredns/middleware"
"github.com/miekg/coredns/middleware/kubernetes/nametemplate"
"github.com/mholt/caddy" "github.com/mholt/caddy"
unversionedapi "k8s.io/client-go/1.5/pkg/api/unversioned" unversionedapi "k8s.io/client-go/1.5/pkg/api/unversioned"
@ -52,8 +51,6 @@ func setup(c *caddy.Controller) error {
func kubernetesParse(c *caddy.Controller) (*Kubernetes, error) { func kubernetesParse(c *caddy.Controller) (*Kubernetes, error) {
k8s := &Kubernetes{ResyncPeriod: defaultResyncPeriod} k8s := &Kubernetes{ResyncPeriod: defaultResyncPeriod}
k8s.NameTemplate = new(nametemplate.Template)
k8s.NameTemplate.SetTemplate(defaultNameTemplate)
k8s.PodMode = PodModeDisabled k8s.PodMode = PodModeDisabled
for c.Next() { for c.Next() {
@ -99,18 +96,6 @@ func kubernetesParse(c *caddy.Controller) (*Kubernetes, error) {
continue continue
} }
return nil, c.ArgErr() return nil, c.ArgErr()
case "template":
args := c.RemainingArgs()
if len(args) > 0 {
template := strings.Join(args, "")
err := k8s.NameTemplate.SetTemplate(template)
if err != nil {
return nil, err
}
continue
}
return nil, c.ArgErr()
case "namespaces": case "namespaces":
args := c.RemainingArgs() args := c.RemainingArgs()
if len(args) > 0 { if len(args) > 0 {
@ -164,7 +149,6 @@ func kubernetesParse(c *caddy.Controller) (*Kubernetes, error) {
} }
const ( const (
defaultNameTemplate = "{service}.{namespace}.{type}.{zone}"
defaultResyncPeriod = 5 * time.Minute defaultResyncPeriod = 5 * time.Minute
defaultPodMode = PodModeDisabled defaultPodMode = PodModeDisabled
) )

View file

@ -16,7 +16,6 @@ func TestKubernetesParse(t *testing.T) {
shouldErr bool // true if test case is exected to produce an error. shouldErr bool // true if test case is exected to produce an error.
expectedErrContent string // substring from the expected error. Empty for positive cases. expectedErrContent string // substring from the expected error. Empty for positive cases.
expectedZoneCount int // expected count of defined zones. expectedZoneCount int // expected count of defined zones.
expectedNTValid bool // NameTemplate to be initialized and valid
expectedNSCount int // expected count of namespaces. expectedNSCount int // expected count of namespaces.
expectedResyncPeriod time.Duration // expected resync period value expectedResyncPeriod time.Duration // expected resync period value
expectedLabelSelector string // expected label selector value expectedLabelSelector string // expected label selector value
@ -28,7 +27,6 @@ func TestKubernetesParse(t *testing.T) {
false, false,
"", "",
1, 1,
true,
0, 0,
defaultResyncPeriod, defaultResyncPeriod,
"", "",
@ -39,7 +37,6 @@ func TestKubernetesParse(t *testing.T) {
false, false,
"", "",
2, 2,
true,
0, 0,
defaultResyncPeriod, defaultResyncPeriod,
"", "",
@ -51,7 +48,6 @@ func TestKubernetesParse(t *testing.T) {
false, false,
"", "",
1, 1,
true,
0, 0,
defaultResyncPeriod, defaultResyncPeriod,
"", "",
@ -64,20 +60,6 @@ func TestKubernetesParse(t *testing.T) {
false, false,
"", "",
1, 1,
true,
0,
defaultResyncPeriod,
"",
},
{
"template keyword with valid template",
`kubernetes coredns.local {
template {service}.{namespace}.{zone}
}`,
false,
"",
1,
true,
0, 0,
defaultResyncPeriod, defaultResyncPeriod,
"", "",
@ -90,7 +72,6 @@ func TestKubernetesParse(t *testing.T) {
false, false,
"", "",
1, 1,
true,
1, 1,
defaultResyncPeriod, defaultResyncPeriod,
"", "",
@ -103,7 +84,6 @@ func TestKubernetesParse(t *testing.T) {
false, false,
"", "",
1, 1,
true,
2, 2,
defaultResyncPeriod, defaultResyncPeriod,
"", "",
@ -116,7 +96,6 @@ func TestKubernetesParse(t *testing.T) {
false, false,
"", "",
1, 1,
true,
0, 0,
30 * time.Second, 30 * time.Second,
"", "",
@ -129,7 +108,6 @@ func TestKubernetesParse(t *testing.T) {
false, false,
"", "",
1, 1,
true,
0, 0,
15 * time.Minute, 15 * time.Minute,
"", "",
@ -142,7 +120,6 @@ func TestKubernetesParse(t *testing.T) {
false, false,
"", "",
1, 1,
true,
0, 0,
defaultResyncPeriod, defaultResyncPeriod,
"environment=prod", "environment=prod",
@ -155,7 +132,6 @@ func TestKubernetesParse(t *testing.T) {
false, false,
"", "",
1, 1,
true,
0, 0,
defaultResyncPeriod, defaultResyncPeriod,
"application=nginx,environment in (production,qa,staging)", "application=nginx,environment in (production,qa,staging)",
@ -165,14 +141,12 @@ func TestKubernetesParse(t *testing.T) {
`kubernetes coredns.local test.local { `kubernetes coredns.local test.local {
resyncperiod 15m resyncperiod 15m
endpoint http://localhost:8080 endpoint http://localhost:8080
template {service}.{namespace}.{zone}
namespaces demo test namespaces demo test
labels environment in (production, staging, qa),application=nginx labels environment in (production, staging, qa),application=nginx
}`, }`,
false, false,
"", "",
2, 2,
true,
2, 2,
15 * time.Minute, 15 * time.Minute,
"application=nginx,environment in (production,qa,staging)", "application=nginx,environment in (production,qa,staging)",
@ -184,7 +158,6 @@ func TestKubernetesParse(t *testing.T) {
true, true,
"Kubernetes setup called without keyword 'kubernetes' in Corefile", "Kubernetes setup called without keyword 'kubernetes' in Corefile",
-1, -1,
false,
-1, -1,
defaultResyncPeriod, defaultResyncPeriod,
"", "",
@ -195,7 +168,6 @@ func TestKubernetesParse(t *testing.T) {
true, true,
"Zone name must be provided for kubernetes middleware", "Zone name must be provided for kubernetes middleware",
-1, -1,
true,
0, 0,
defaultResyncPeriod, defaultResyncPeriod,
"", "",
@ -208,37 +180,10 @@ func TestKubernetesParse(t *testing.T) {
true, true,
"Wrong argument count or unexpected line ending after 'endpoint'", "Wrong argument count or unexpected line ending after 'endpoint'",
-1, -1,
true,
-1, -1,
defaultResyncPeriod, defaultResyncPeriod,
"", "",
}, },
{
"template keyword without a template value",
`kubernetes coredns.local {
template
}`,
true,
"Wrong argument count or unexpected line ending after 'template'",
-1,
false,
0,
defaultResyncPeriod,
"",
},
{
"template keyword with an invalid template value",
`kubernetes coredns.local {
template {namespace}.{zone}
}`,
true,
"Record name template does not pass NameTemplate validation",
-1,
false,
0,
defaultResyncPeriod,
"",
},
{ {
"namespace keyword without a namespace value", "namespace keyword without a namespace value",
`kubernetes coredns.local { `kubernetes coredns.local {
@ -247,7 +192,6 @@ func TestKubernetesParse(t *testing.T) {
true, true,
"Parse error: Wrong argument count or unexpected line ending after 'namespaces'", "Parse error: Wrong argument count or unexpected line ending after 'namespaces'",
-1, -1,
true,
-1, -1,
defaultResyncPeriod, defaultResyncPeriod,
"", "",
@ -260,7 +204,6 @@ func TestKubernetesParse(t *testing.T) {
true, true,
"Wrong argument count or unexpected line ending after 'resyncperiod'", "Wrong argument count or unexpected line ending after 'resyncperiod'",
-1, -1,
true,
0, 0,
0 * time.Minute, 0 * time.Minute,
"", "",
@ -273,7 +216,6 @@ func TestKubernetesParse(t *testing.T) {
true, true,
"Unable to parse resync duration value. Value provided was ", "Unable to parse resync duration value. Value provided was ",
-1, -1,
true,
0, 0,
0 * time.Second, 0 * time.Second,
"", "",
@ -286,7 +228,6 @@ func TestKubernetesParse(t *testing.T) {
true, true,
"Unable to parse resync duration value. Value provided was ", "Unable to parse resync duration value. Value provided was ",
-1, -1,
true,
0, 0,
0 * time.Second, 0 * time.Second,
"", "",
@ -299,7 +240,6 @@ func TestKubernetesParse(t *testing.T) {
true, true,
"Wrong argument count or unexpected line ending after 'labels'", "Wrong argument count or unexpected line ending after 'labels'",
-1, -1,
true,
0, 0,
0 * time.Second, 0 * time.Second,
"", "",
@ -312,7 +252,6 @@ func TestKubernetesParse(t *testing.T) {
true, true,
"Unable to parse label selector. Value provided was", "Unable to parse label selector. Value provided was",
-1, -1,
true,
0, 0,
0 * time.Second, 0 * time.Second,
"", "",
@ -354,16 +293,6 @@ func TestKubernetesParse(t *testing.T) {
t.Errorf("Test %d: Expected kubernetes controller to be initialized with %d zones, instead found %d zones: '%v' for input '%s'", i, test.expectedZoneCount, foundZoneCount, k8sController.Zones, test.input) t.Errorf("Test %d: Expected kubernetes controller to be initialized with %d zones, instead found %d zones: '%v' for input '%s'", i, test.expectedZoneCount, foundZoneCount, k8sController.Zones, test.input)
} }
// NameTemplate
if k8sController.NameTemplate == nil {
t.Errorf("Test %d: Expected kubernetes controller to be initialized with a NameTemplate. Instead found '%v' for input '%s'", i, k8sController.NameTemplate, test.input)
} else {
foundNTValid := k8sController.NameTemplate.IsValid()
if foundNTValid != test.expectedNTValid {
t.Errorf("Test %d: Expected NameTemplate validity to be '%v', instead found '%v' for input '%s'", i, test.expectedNTValid, foundNTValid, test.input)
}
}
// Namespaces // Namespaces
foundNSCount := len(k8sController.Namespaces) foundNSCount := len(k8sController.Namespaces)
if foundNSCount != test.expectedNSCount { if foundNSCount != test.expectedNSCount {

View file

@ -105,7 +105,7 @@ var dnsTestCases = []test.Case{
}, },
//TODO: Fix below to all use test.SRV not test.A! //TODO: Fix below to all use test.SRV not test.A!
{ {
Qname: "_*._*.svc-1-a.test-1.svc.cluster.local.", Qtype: dns.TypeSRV, Qname: "*._TcP.svc-1-a.test-1.svc.cluster.local.", Qtype: dns.TypeSRV,
Rcode: dns.RcodeSuccess, Rcode: dns.RcodeSuccess,
Answer: []dns.RR{ Answer: []dns.RR{
test.SRV("_http._tcp.svc-1-a.test-1.svc.cluster.local. 303 IN SRV 10 100 80 svc-1-a.test-1.svc.cluster.local."), test.SRV("_http._tcp.svc-1-a.test-1.svc.cluster.local. 303 IN SRV 10 100 80 svc-1-a.test-1.svc.cluster.local."),
@ -113,12 +113,12 @@ var dnsTestCases = []test.Case{
}, },
}, },
{ {
Qname: "_*._*.bogusservice.test-1.svc.cluster.local.", Qtype: dns.TypeSRV, Qname: "*.*.bogusservice.test-1.svc.cluster.local.", Qtype: dns.TypeSRV,
Rcode: dns.RcodeNameError, Rcode: dns.RcodeNameError,
Answer: []dns.RR{}, Answer: []dns.RR{},
}, },
{ {
Qname: "_*._*.svc-1-a.*.svc.cluster.local.", Qtype: dns.TypeSRV, Qname: "*.any.svc-1-a.*.svc.cluster.local.", Qtype: dns.TypeSRV,
Rcode: dns.RcodeSuccess, Rcode: dns.RcodeSuccess,
Answer: []dns.RR{ Answer: []dns.RR{
test.SRV("_http._tcp.svc-1-a.test-1.svc.cluster.local. 303 IN SRV 10 100 80 svc-1-a.test-1.svc.cluster.local."), test.SRV("_http._tcp.svc-1-a.test-1.svc.cluster.local. 303 IN SRV 10 100 80 svc-1-a.test-1.svc.cluster.local."),
@ -126,7 +126,7 @@ var dnsTestCases = []test.Case{
}, },
}, },
{ {
Qname: "_*._*.svc-1-a.any.svc.cluster.local.", Qtype: dns.TypeSRV, Qname: "ANY.*.svc-1-a.any.svc.cluster.local.", Qtype: dns.TypeSRV,
Rcode: dns.RcodeSuccess, Rcode: dns.RcodeSuccess,
Answer: []dns.RR{ Answer: []dns.RR{
test.SRV("_http._tcp.svc-1-a.test-1.svc.cluster.local. 303 IN SRV 10 100 80 svc-1-a.test-1.svc.cluster.local."), test.SRV("_http._tcp.svc-1-a.test-1.svc.cluster.local. 303 IN SRV 10 100 80 svc-1-a.test-1.svc.cluster.local."),
@ -134,17 +134,17 @@ var dnsTestCases = []test.Case{
}, },
}, },
{ {
Qname: "_*._*.bogusservice.*.svc.cluster.local.", Qtype: dns.TypeSRV, Qname: "*.*.bogusservice.*.svc.cluster.local.", Qtype: dns.TypeSRV,
Rcode: dns.RcodeNameError, Rcode: dns.RcodeNameError,
Answer: []dns.RR{}, Answer: []dns.RR{},
}, },
{ {
Qname: "_*._*.bogusservice.any.svc.cluster.local.", Qtype: dns.TypeSRV, Qname: "*.*.bogusservice.any.svc.cluster.local.", Qtype: dns.TypeSRV,
Rcode: dns.RcodeNameError, Rcode: dns.RcodeNameError,
Answer: []dns.RR{}, Answer: []dns.RR{},
}, },
{ {
Qname: "_c-port._*.*.test-1.svc.cluster.local.", Qtype: dns.TypeSRV, Qname: "_c-port._UDP.*.test-1.svc.cluster.local.", Qtype: dns.TypeSRV,
Rcode: dns.RcodeSuccess, Rcode: dns.RcodeSuccess,
Answer: []dns.RR{ Answer: []dns.RR{
test.SRV("_c-port._udp.svc-c.test-1.svc.cluster.local. 303 IN SRV 10 100 1234 svc-c.test-1.svc.cluster.local."), test.SRV("_c-port._udp.svc-c.test-1.svc.cluster.local. 303 IN SRV 10 100 1234 svc-c.test-1.svc.cluster.local."),
@ -153,7 +153,7 @@ var dnsTestCases = []test.Case{
}, },
}, },
{ {
Qname: "_*._tcp.any.test-1.svc.cluster.local.", Qtype: dns.TypeSRV, Qname: "*._tcp.any.test-1.svc.cluster.local.", Qtype: dns.TypeSRV,
Rcode: dns.RcodeSuccess, Rcode: dns.RcodeSuccess,
Answer: []dns.RR{ Answer: []dns.RR{
test.SRV("_http._tcp.svc-1-a.test-1.svc.cluster.local. 303 IN SRV 10 100 80 svc-1-a.test-1.svc.cluster.local."), test.SRV("_http._tcp.svc-1-a.test-1.svc.cluster.local. 303 IN SRV 10 100 80 svc-1-a.test-1.svc.cluster.local."),
@ -162,12 +162,12 @@ var dnsTestCases = []test.Case{
}, },
}, },
{ {
Qname: "_*._*.any.test-2.svc.cluster.local.", Qtype: dns.TypeSRV, Qname: "*.*.any.test-2.svc.cluster.local.", Qtype: dns.TypeSRV,
Rcode: dns.RcodeNameError, Rcode: dns.RcodeNameError,
Answer: []dns.RR{}, Answer: []dns.RR{},
}, },
{ {
Qname: "_*._*.*.test-2.svc.cluster.local.", Qtype: dns.TypeSRV, Qname: "*.*.*.test-2.svc.cluster.local.", Qtype: dns.TypeSRV,
Rcode: dns.RcodeNameError, Rcode: dns.RcodeNameError,
Answer: []dns.RR{}, Answer: []dns.RR{},
}, },
@ -180,18 +180,18 @@ var dnsTestCases = []test.Case{
}, },
}, },
{ {
Qname: "_*.svc-1-a.test-1.svc.cluster.local.", Qtype: dns.TypeSRV, Qname: "*.svc-1-a.test-1.svc.cluster.local.", Qtype: dns.TypeSRV,
Rcode: dns.RcodeNameError, Rcode: dns.RcodeServerFailure,
Answer: []dns.RR{}, Answer: []dns.RR{},
}, },
{ {
Qname: "_*._not-udp-or-tcp.svc-1-a.test-1.svc.cluster.local.", Qtype: dns.TypeSRV, Qname: "*._not-udp-or-tcp.svc-1-a.test-1.svc.cluster.local.", Qtype: dns.TypeSRV,
Rcode: dns.RcodeNameError, Rcode: dns.RcodeServerFailure,
Answer: []dns.RR{}, Answer: []dns.RR{},
}, },
{ {
Qname: "svc-1-a.test-1.svc.cluster.local.", Qtype: dns.TypeSRV, Qname: "svc-1-a.test-1.svc.cluster.local.", Qtype: dns.TypeSRV,
Rcode: dns.RcodeNameError, Rcode: dns.RcodeServerFailure,
Answer: []dns.RR{}, Answer: []dns.RR{},
}, },
{ {