Allow CoreDNS version strings to contain sufixes

Author: 0rax

pkg/dns/dns.go

@@ -39,7 +39,12 @@ const (
 	traefikMeshBlockTrailer = "#### End Traefik Mesh Block"
 )
 
-var versionCoreDNS17 = goversion.Must(goversion.NewVersion("1.7"))
+var (
+	versionCoreDNS17 = goversion.Must(goversion.NewVersion("1.7"))
+
+	versionCoreDNSMin = goversion.Must(goversion.NewVersion("1.3"))
+	versionCoreDNSMax = goversion.Must(goversion.NewVersion("1.8"))
+)
 
 // Client holds the client for interacting with the k8s DNS system.
 type Client struct {
@@ -98,13 +103,8 @@ func (c *Client) coreDNSMatch(ctx context.Context) (bool, error) {
 		return false, err
 	}
 
-	versionConstraint, err := goversion.NewConstraint(">= 1.3, < 1.8")
-	if err != nil {
-		return false, err
-	}
-
-	if !versionConstraint.Check(version) {
-		c.logger.Debugf("CoreDNS version is not supported, must satisfy %q, got %q", versionConstraint, version)
+	if !(version.GreaterThanOrEqual(versionCoreDNSMin) && version.LessThan(versionCoreDNSMax)) {
+		c.logger.Debugf(`CoreDNS version is not supported, must satisfy ">= %s, < %s", got %q`, versionCoreDNSMin, versionCoreDNSMax, version)
 
 		return false, fmt.Errorf("unsupported CoreDNS version %q", version)
 	}

pkg/dns/dns_test.go

@@ -26,6 +26,12 @@ func TestCheckDNSProvider(t *testing.T) {
 			expProvider: CoreDNS,
 			expErr:      false,
 		},
+		{
+			desc:        "CoreDNS supported version with suffix",
+			mockFile:    "checkdnsprovider_supported_version_suffix.yaml",
+			expProvider: CoreDNS,
+			expErr:      false,
+		},
 		{
 			desc:        "KubeDNS",
 			mockFile:    "checkdnsprovider_kubedns.yaml",

pkg/dns/testdata/checkdnsprovider_supported_version_suffix.yaml

@@ -0,0 +1,13 @@
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: coredns
+  namespace: kube-system
+spec:
+  template:
+    spec:
+      containers:
+        - name: coredns
+          image: image-registry.dkr.ecr.eu-west-1.amazonaws.com/eks/coredns:v1.6.6-eksbuild.1
+        - name: titi
+          image: titi/toto:latest