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-rw-r--r--middleware/kubernetes/kubernetes.go203
1 files changed, 120 insertions, 83 deletions
diff --git a/middleware/kubernetes/kubernetes.go b/middleware/kubernetes/kubernetes.go
index 25c8cab3c..d6d93f809 100644
--- a/middleware/kubernetes/kubernetes.go
+++ b/middleware/kubernetes/kubernetes.go
@@ -2,111 +2,148 @@
package kubernetes
import (
- "fmt"
- "strings"
+ "errors"
+ "fmt"
"time"
"github.com/miekg/coredns/middleware"
- "github.com/miekg/coredns/middleware/kubernetes/msg"
k8sc "github.com/miekg/coredns/middleware/kubernetes/k8sclient"
+ "github.com/miekg/coredns/middleware/kubernetes/msg"
+ "github.com/miekg/coredns/middleware/kubernetes/nametemplate"
+ "github.com/miekg/coredns/middleware/kubernetes/util"
"github.com/miekg/coredns/middleware/proxy"
-// "github.com/miekg/coredns/middleware/singleflight"
+ // "github.com/miekg/coredns/middleware/singleflight"
- "github.com/miekg/dns"
+ "github.com/miekg/dns"
"golang.org/x/net/context"
)
type Kubernetes struct {
- Next middleware.Handler
- Zones []string
- Proxy proxy.Proxy // Proxy for looking up names during the resolution process
- Ctx context.Context
-// Inflight *singleflight.Group
- APIConn *k8sc.K8sConnector
+ Next middleware.Handler
+ Zones []string
+ Proxy proxy.Proxy // Proxy for looking up names during the resolution process
+ Ctx context.Context
+ // Inflight *singleflight.Group
+ APIConn *k8sc.K8sConnector
+ NameTemplate *nametemplate.NameTemplate
+ Namespaces *[]string
}
-
+// getZoneForName returns the zone string that matches the name and a
+// list of the DNS labels from name that are within the zone.
+// For example, if "coredns.local" is a zone configured for the
+// Kubernetes middleware, then getZoneForName("a.b.coredns.local")
+// will return ("coredns.local", ["a", "b"]).
func (g Kubernetes) getZoneForName(name string) (string, []string) {
- /*
- * getZoneForName returns the zone string that matches the name and a
- * list of the DNS labels from name that are within the zone.
- * For example, if "coredns.local" is a zone configured for the
- * Kubernetes middleware, then getZoneForName("a.b.coredns.local")
- * will return ("coredns.local", ["a", "b"]).
- */
- var zone string
- var serviceSegments []string
-
- for _, z := range g.Zones {
- if dns.IsSubDomain(z, name) {
- zone = z
-
- serviceSegments = dns.SplitDomainName(name)
- serviceSegments = serviceSegments[:len(serviceSegments) - dns.CountLabel(zone)]
- break
- }
- }
-
- return zone, serviceSegments
-}
+ var zone string
+ var serviceSegments []string
+ for _, z := range g.Zones {
+ if dns.IsSubDomain(z, name) {
+ zone = z
+
+ serviceSegments = dns.SplitDomainName(name)
+ serviceSegments = serviceSegments[:len(serviceSegments)-dns.CountLabel(zone)]
+ break
+ }
+ }
+
+ return zone, serviceSegments
+}
// 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
// for instance.
func (g Kubernetes) Records(name string, exact bool) ([]msg.Service, error) {
+ var (
+ serviceName string
+ namespace string
+ typeName string
+ )
+
+ fmt.Println("enter Records('", name, "', ", exact, ")")
+ zone, serviceSegments := g.getZoneForName(name)
+
+ /*
+ // For initial implementation, assume namespace is first serviceSegment
+ // and service name is remaining segments.
+ serviceSegLen := len(serviceSegments)
+ if serviceSegLen >= 2 {
+ namespace = serviceSegments[serviceSegLen-1]
+ serviceName = strings.Join(serviceSegments[:serviceSegLen-1], ".")
+ }
+ // else we are looking up the zone. So handle the NS, SOA records etc.
+ */
+
+ // TODO: Implementation above globbed together segments for the serviceName if
+ // multiple segments remained. Determine how to do similar globbing using
+ // the template-based implementation.
+ namespace = g.NameTemplate.GetNamespaceFromSegmentArray(serviceSegments)
+ serviceName = g.NameTemplate.GetServiceFromSegmentArray(serviceSegments)
+ typeName = g.NameTemplate.GetTypeFromSegmentArray(serviceSegments)
+
+ fmt.Println("[debug] exact: ", exact)
+ fmt.Println("[debug] zone: ", zone)
+ fmt.Println("[debug] servicename: ", serviceName)
+ fmt.Println("[debug] namespace: ", namespace)
+ fmt.Println("[debug] typeName: ", typeName)
+ fmt.Println("[debug] APIconn: ", g.APIConn)
+
+ // TODO: Implement wildcard support to allow blank namespace value
+ if namespace == "" {
+ err := errors.New("Parsing query string did not produce a namespace value")
+ fmt.Printf("[ERROR] %v\n", err)
+ return nil, err
+ }
- fmt.Println("enter Records('", name, "', ", exact, ")")
-
- zone, serviceSegments := g.getZoneForName(name)
+ // Abort if the namespace is not published per CoreFile
+ if g.Namespaces != nil && !util.StringInSlice(namespace, *g.Namespaces) {
+ return nil, nil
+ }
- var serviceName string
- var namespace string
+ k8sItems, err := g.APIConn.GetServiceItemsInNamespace(namespace, serviceName)
+ fmt.Println("[debug] k8s items:", k8sItems)
- // For initial implementation, assume namespace is first serviceSegment
- // and service name is remaining segments.
- serviceSegLen := len(serviceSegments)
- if serviceSegLen >= 2 {
- namespace = serviceSegments[serviceSegLen-1]
- serviceName = strings.Join(serviceSegments[:serviceSegLen-1], ".")
- }
- // else we are looking up the zone. So handle the NS, SOA records etc.
+ if err != nil {
+ fmt.Printf("[ERROR] Got error while looking up ServiceItems. Error is: %v\n", err)
+ return nil, err
+ }
+ if k8sItems == nil {
+ // Did not find item in k8s
+ return nil, nil
+ }
- fmt.Println("[debug] zone: ", zone)
- fmt.Println("[debug] servicename: ", serviceName)
- fmt.Println("[debug] namespace: ", namespace)
- fmt.Println("[debug] APIconn: ", g.APIConn)
+ // test := g.NameTemplate.GetRecordNameFromNameValues(nametemplate.NameValues{ServiceName: serviceName, TypeName: typeName, Namespace: namespace, Zone: zone})
+ // fmt.Printf("[debug] got recordname %v\n", test)
- k8sItem := g.APIConn.GetServiceItemInNamespace(namespace, serviceName)
- fmt.Println("[debug] k8s item:", k8sItem)
+ records := g.getRecordsForServiceItems(k8sItems, name)
- switch {
- case exact && k8sItem == nil:
- fmt.Println("here2")
- return nil, nil
- }
+ return records, nil
+}
- if k8sItem == nil {
- // Did not find item in k8s
- return nil, nil
- }
+// TODO: assemble name from parts found in k8s data based on name template rather than reusing query string
+func (g Kubernetes) getRecordsForServiceItems(serviceItems []*k8sc.ServiceItem, name string) []msg.Service {
+ var records []msg.Service
- fmt.Println("[debug] clusterIP:", k8sItem.Spec.ClusterIP)
+ for _, item := range serviceItems {
+ fmt.Println("[debug] clusterIP:", item.Spec.ClusterIP)
+ for _, p := range item.Spec.Ports {
+ fmt.Println("[debug] port:", p.Port)
+ }
- for _, p := range k8sItem.Spec.Ports {
- fmt.Println("[debug] host:", name)
- fmt.Println("[debug] port:", p.Port)
- }
+ clusterIP := item.Spec.ClusterIP
- clusterIP := k8sItem.Spec.ClusterIP
- var records []msg.Service
- for _, p := range k8sItem.Spec.Ports{
- s := msg.Service{Host: clusterIP, Port: p.Port}
- records = append(records, s)
- }
+ s := msg.Service{Host: name}
+ records = append(records, s)
+ for _, p := range item.Spec.Ports {
+ s := msg.Service{Host: clusterIP, Port: p.Port}
+ records = append(records, s)
+ }
+ }
- return records, nil
+ fmt.Printf("[debug] records from getRecordsForServiceItems(): %v\n", records)
+ return records
}
/*
@@ -121,13 +158,13 @@ func (g Kubernetes) Get(path string, recursive bool) (bool, error) {
*/
func (g Kubernetes) splitDNSName(name string) []string {
- l := dns.SplitDomainName(name)
+ l := dns.SplitDomainName(name)
- for i, j := 0, len(l)-1; i < j; i, j = i+1, j-1 {
- l[i], l[j] = l[j], l[i]
- }
+ for i, j := 0, len(l)-1; i < j; i, j = i+1, j-1 {
+ l[i], l[j] = l[j], l[i]
+ }
- return l
+ return l
}
// skydns/local/skydns/east/staging/web
@@ -215,9 +252,9 @@ func isKubernetesNameError(err error) bool {
}
const (
- priority = 10 // default priority when nothing is set
- ttl = 300 // default ttl when nothing is set
- minTtl = 60
- hostmaster = "hostmaster"
+ priority = 10 // default priority when nothing is set
+ ttl = 300 // default ttl when nothing is set
+ minTtl = 60
+ hostmaster = "hostmaster"
k8sTimeout = 5 * time.Second
)
generated by cgit v1.2.3 (git 2.39.1) at 2025-08-03 16:33:36 +0000