Adding CoreDNS rewrite

cli/src/Vdk/Services/ReverseProxyClient.cs

@@ -13,13 +13,11 @@
     private readonly IDockerEngine _docker;
     private readonly Func<string, IKubernetesClient> _client;
     private readonly IConsole _console;
-
-
+
     private static readonly string NginxConf = Path.Combine("vega.conf");
- 
+
     private readonly IKindClient _kind;
 
-
     // ReverseProxyHostPort is 443 by default, unless REVERSE_PROXY_HOST_PORT is set as an env var
     private int ReverseProxyHostPort = GetEnvironmentVariableAsInt("REVERSE_PROXY_HOST_PORT", 443);
 
@@ -62,7 +60,7 @@
                     if (tuple is { isVdk: true, master: not null } && tuple.master.HttpsHostPort.HasValue)
                     {
                         _console.WriteLine($" - Adding cluster {tuple.name} to reverse proxy configuration");
                         UpsertCluster(tuple.name, tuple.master.HttpsHostPort.Value, tuple.master.HttpHostPort.Value, false);
                     }
                 });
             }
@@ -105,7 +103,7 @@
             return true;
         }
 
         return false;
     }
 
     private void InitConfFile(FileInfo conf)
@@ -147,6 +145,15 @@
     }
 
     public void UpsertCluster(string clusterName, int targetPortHttps, int targetPortHttp, bool reload = true)
+    {
+        PatchNginxConfig(clusterName, targetPortHttps);
+        if (CreateTlsSecret(clusterName)) return;
+        PatchCoreDns(clusterName);
+        if (reload)
+            ReloadConfigs();
+    }
+
+    private void PatchNginxConfig(string clusterName, int targetPortHttps)
     {
         // create a new server block in the nginx conf pointing to the target port listening on the https://clusterName.dev-k8s.cloud domain
         // reload the nginx configuration
@@ -179,7 +186,112 @@
             _console.WriteWarning($"Error clearing cluster configuration ({NginxConf}): {e.Message}");
             _console.WriteWarning("Please check the configuration and try again.");
         }
+    }
 
+    private bool PatchCoreDns(string clusterName)
+    {
+        // let's wait for and find the ingress controller service.
+        V1Service? ingressService = null;
+        var attempts = 0;
+        do
+        {
+            // check up to 10 times , waiting 5 seconds each time
+            ingressService = _client(clusterName).Get<V1Service>("ingress-nginx-controller", "ingress-nginx");
+            if (ingressService == null)
+            {
+                _console.WriteLine("Waiting for ingress-nginx-controller service to be available...");
+                Thread.Sleep(5000);
+                attempts++;
+            }
+            else
+            {
+                _console.WriteLine("Ingress-nginx-controller service found.");
+                break;
+            }
+        }
+        while (ingressService == null && attempts < 6);
+        if (ingressService == null)
+        {
+            _console.WriteError("Ingress-nginx-controller service not found. Please check the configuration and try again.");
+            return false;
+        }
+        var rewriteString = $"    rewrite name {clusterName}.dev-k8s.cloud {ingressService.Name()}.{ingressService.Namespace()}.svc.cluster.local";
+        // now read the CoreDNS configmap and add the clusterName.dev-k8s.cloud entry to it
+        var corednsConfigMap = _client(clusterName).Get<V1ConfigMap>("coredns", "kube-system");
+        if (corednsConfigMap == null)
+        {
+            _console.WriteError("CoreDNS configmap not found. Please check the configuration and try again.");
+            return false;
+        }
+        _console.WriteLine("Patching CoreDNS configmap with new cluster entry.");
+        var corednsData = corednsConfigMap.Data;
+        if (corednsData == null)
+        {
+            corednsData = new Dictionary<string, string>();
+        }
+        // extract the corefile from the configmap data
+        if (!corednsData.TryGetValue("Corefile", out var corefile))
+        {
+            _console.WriteError("CoreDNS Corefile not found in configmap. Please check the configuration and try again.");
+            return false;
+        }
+        // add the clusterName.dev-k8s.cloud rewrite entry to the Corefile after the kubernetes block
+        // if the line already exists, do not add it again
+        if (corefile.Contains(rewriteString))
+        {
+            _console.WriteLine("CoreDNS Corefile already contains the rewrite entry for the cluster. No changes made.");
+            return true;
+        }
+        var lines = corefile.Split([Environment.NewLine], StringSplitOptions.RemoveEmptyEntries).ToList();
+
+        var kubernetesBlockIndex = lines.FindIndex(line => line.Trim().StartsWith("kubernetes"));
+
+        if (kubernetesBlockIndex == -1)
+        {
+            _console.WriteError("CoreDNS Corefile does not contain a kubernetes block. Please check the configuration and try again.");
+            return false;
+        }
+
+        // insert the new entry after the kubernetes block by searching for the closing brace then inserting it
+
+        var closingBraceIndex = lines.FindIndex(kubernetesBlockIndex, line => line.Trim() == "}");
+        if (closingBraceIndex == -1)
+        {
+            _console.WriteError("CoreDNS Corefile does not contain a closing brace for the kubernetes block. Please check the configuration and try again.");
+            return false;
+        }
+        lines.Insert(closingBraceIndex, rewriteString);
+
+        // join the lines back into a single string
+        var updatedCorefile = string.Join(Environment.NewLine, lines);
+
+        // update the configmap data with the new Corefile
+        corednsData["Corefile"] = updatedCorefile;
+
+        // update the configmap
+        corednsConfigMap.Data = corednsData;
+        _client(clusterName).Update(corednsConfigMap);
+        _console.WriteLine("CoreDNS configmap updated successfully.");
+
+        // restart the coredns
+        _console.WriteLine("Restarting CoreDNS pods to apply changes.");
+        var corednsPods = _client(clusterName).List<V1Pod>("kube-system", labelSelector: "k8s-app=kube-dns");
+        if (!corednsPods.Any())
+        {
+            _console.WriteError("No CoreDNS pods found. Please check the configuration and try again.");
+            return false;
+        }
+        foreach (var pod in corednsPods)
+        {
+            _console.WriteLine($"Deleting CoreDNS pod {pod.Name()} to apply changes.");
+            _client(clusterName).Delete(pod);
+        }
+        _console.WriteLine("CoreDNS pods deleted successfully. They will be recreated automatically.");
+        return true;
+    }
+
+    private bool CreateTlsSecret(string clusterName)
+    {
         // wait until the namespace vega exists before proceeding with the secrets creation
         bool nsVegaExists = false;
         int nTimesWaiting = 0;
@@ -204,7 +316,7 @@
         if (nTimesWaiting >= maxTimesWaiting)
         {
             _console.WriteError("Namespace 'vega-system' does not exist after waiting. Please check the configuration and try again.");
-            return;
+            return true;
         }
 
         // write the cert secret to the cluster
@@ -229,8 +341,7 @@
         }
         _console.WriteLine("Creating vega-system secret");
         _client(clusterName).Create(tls);
-        if (reload)
-            ReloadConfigs();
+        return false;
     }
 
     private void ReloadConfigs()
@@ -306,7 +417,7 @@
 
     private static int GetEnvironmentVariableAsInt(string variableName, int defaultValue = 0)
     {
         string strValue = Environment.GetEnvironmentVariable(variableName);
         if (strValue != null && int.TryParse(strValue, out int intValue))
         {
             return intValue;

cli/tests/Vdk.Tests/ReverseProxyClientTests.cs

@@ -15,12 +15,12 @@ public class ReverseProxyClientTests
         private readonly Mock<IDockerEngine> _dockerMock = new();
         private readonly Mock<IConsole> _consoleMock = new();
         private readonly Mock<IKindClient> _kindMock = new();
-        private readonly Mock<IKubernetesClient> _k8sMock = new();
+        private readonly Mock<IKubernetesClient> _kubeClientMock = new();
         private readonly Func<string, IKubernetesClient> _clientFunc;
 
         public ReverseProxyClientTests()
         {
-            _clientFunc = _ => _k8sMock.Object;
+            _clientFunc = _ => _kubeClientMock.Object;
         }
 
         [Fact]
@@ -66,5 +66,149 @@ public void InitConfFile_CreatesFileAndWritesConfig()
             File.ReadAllText(tempFile).Should().Contain("server {");
             File.Delete(tempFile);
         }
+
+        [Fact]
+        public void PatchCoreDns_ReturnsFalse_WhenIngressServiceNotFound()
+        {
+            // Arrange
+            _kubeClientMock.SetupSequence(x => x.Get<V1Service>("ingress-nginx-controller", "ingress-nginx"))
+                .Returns((V1Service?)null);
+            var client = new ReverseProxyClient(_dockerMock.Object, _clientFunc, _consoleMock.Object, _kindMock.Object);
+
+            // Act
+            var result = InvokePatchCoreDns(client, "test-cluster");
+
+            // Assert
+            Assert.False(result);
+            _consoleMock.Verify(x => x.WriteError(It.Is<string>(s => s.Contains("Ingress-nginx-controller service not found"))), Times.Once);
+        }
+
+        [Fact]
+        public void PatchCoreDns_ReturnsFalse_WhenCoreDnsConfigMapNotFound()
+        {
+            // Arrange
+            _kubeClientMock.Setup(x => x.Get<V1Service>("ingress-nginx-controller", "ingress-nginx"))
+                .Returns(new V1Service { Metadata = new V1ObjectMeta { Name = "svc", NamespaceProperty = "ns" } });
+            _kubeClientMock.Setup(x => x.Get<V1ConfigMap>("coredns", "kube-system"))
+                .Returns((V1ConfigMap?)null);
+            var client = new ReverseProxyClient(_dockerMock.Object, _clientFunc, _consoleMock.Object, _kindMock.Object);
+
+            // Act
+            var result = InvokePatchCoreDns(client, "test-cluster");
+
+            // Assert
+            Assert.False(result);
+            _consoleMock.Verify(x => x.WriteError(It.Is<string>(s => s.Contains("CoreDNS configmap not found"))), Times.Once);
+        }
+
+        [Fact]
+        public void PatchCoreDns_ReturnsFalse_WhenCorefileMissing()
+        {
+            // Arrange
+            _kubeClientMock.Setup(x => x.Get<V1Service>("ingress-nginx-controller", "ingress-nginx"))
+                .Returns(new V1Service { Metadata = new V1ObjectMeta { Name = "svc", NamespaceProperty = "ns" } });
+            _kubeClientMock.Setup(x => x.Get<V1ConfigMap>("coredns", "kube-system"))
+                .Returns(new V1ConfigMap { Data = new Dictionary<string, string>() });
+            var client = new ReverseProxyClient(_dockerMock.Object, _clientFunc, _consoleMock.Object, _kindMock.Object);
+
+            // Act
+            var result = InvokePatchCoreDns(client, "test-cluster");
+
+            // Assert
+            Assert.False(result);
+            _consoleMock.Verify(x => x.WriteError(It.Is<string>(s => s.Contains("CoreDNS Corefile not found"))), Times.Once);
+        }
+
+        [Fact]
+        public void PatchCoreDns_ReturnsTrue_WhenRewriteAlreadyExists()
+        {
+            // Arrange
+            var clusterName = "test-cluster";
+            var rewriteString = $"    rewrite name {clusterName}.dev-k8s.cloud svc.ns.svc.cluster.local";
+            var corefile = $"kubernetes cluster.local in-addr.arpa ip6.arpa {{\n}}\n{rewriteString}\n";
+            _kubeClientMock.Setup(x => x.Get<V1Service>("ingress-nginx-controller", "ingress-nginx"))
+                .Returns(new V1Service { Metadata = new V1ObjectMeta { Name = "svc", NamespaceProperty = "ns" } });
+            _kubeClientMock.Setup(x => x.Get<V1ConfigMap>("coredns", "kube-system"))
+                .Returns(new V1ConfigMap { Data = new Dictionary<string, string> { { "Corefile", corefile } } });
+            var client = new ReverseProxyClient(_dockerMock.Object, _clientFunc, _consoleMock.Object, _kindMock.Object);
+
+            // Act
+            var result = InvokePatchCoreDns(client, clusterName);
+
+            // Assert
+            Assert.True(result);
+            _consoleMock.Verify(x => x.WriteLine(It.Is<string>(s => s.Contains("already contains the rewrite entry"))), Times.Once);
+        }
+
+        [Fact]
+        public void PatchCoreDns_ReturnsFalse_WhenNoKubernetesBlock()
+        {
+            // Arrange
+            var corefile = "some unrelated config";
+            _kubeClientMock.Setup(x => x.Get<V1Service>("ingress-nginx-controller", "ingress-nginx"))
+                .Returns(new V1Service { Metadata = new V1ObjectMeta { Name = "svc", NamespaceProperty = "ns" } });
+            _kubeClientMock.Setup(x => x.Get<V1ConfigMap>("coredns", "kube-system"))
+                .Returns(new V1ConfigMap { Data = new Dictionary<string, string> { { "Corefile", corefile } } });
+            var client = new ReverseProxyClient(_dockerMock.Object, _clientFunc, _consoleMock.Object, _kindMock.Object);
+
+            // Act
+            var result = InvokePatchCoreDns(client, "test-cluster");
+
+            // Assert
+            Assert.False(result);
+            _consoleMock.Verify(x => x.WriteError(It.Is<string>(s => s.Contains("does not contain a kubernetes block"))), Times.Once);
+        }
+
+        [Fact]
+        public void PatchCoreDns_ReturnsFalse_WhenNoClosingBrace()
+        {
+            // Arrange
+            var corefile = "kubernetes cluster.local in-addr.arpa ip6.arpa {";
+            _kubeClientMock.Setup(x => x.Get<V1Service>("ingress-nginx-controller", "ingress-nginx"))
+                .Returns(new V1Service { Metadata = new V1ObjectMeta { Name = "svc", NamespaceProperty = "ns" } });
+            _kubeClientMock.Setup(x => x.Get<V1ConfigMap>("coredns", "kube-system"))
+                .Returns(new V1ConfigMap { Data = new Dictionary<string, string> { { "Corefile", corefile } } });
+            var client = new ReverseProxyClient(_dockerMock.Object, _clientFunc, _consoleMock.Object, _kindMock.Object);
+
+            // Act
+            var result = InvokePatchCoreDns(client, "test-cluster");
+
+            // Assert
+            Assert.False(result);
+            _consoleMock.Verify(x => x.WriteError(It.Is<string>(s => s.Contains("does not contain a closing brace"))), Times.Once);
+        }
+
+        [Fact]
+        public void PatchCoreDns_UpdatesConfigMapAndRestartsPods()
+        {
+            // Arrange
+            var clusterName = "test-cluster";
+            var corefile = $"kubernetes cluster.local in-addr.arpa ip6.arpa {{{Environment.NewLine}}}{Environment.NewLine}";
+            var configMap = new V1ConfigMap { Data = new Dictionary<string, string> { { "Corefile", corefile } } };
+            var pod = new V1Pod { Metadata = new V1ObjectMeta { Name = "coredns-1" } };
+            _kubeClientMock.Setup(x => x.Get<V1Service>("ingress-nginx-controller", "ingress-nginx"))
+                .Returns(new V1Service { Metadata = new V1ObjectMeta { Name = "svc", NamespaceProperty = "ns" } });
+            _kubeClientMock.Setup(x => x.Get<V1ConfigMap>("coredns", "kube-system"))
+                .Returns(configMap);
+            _kubeClientMock.Setup(x => x.List<V1Pod>("kube-system", It.IsAny<string>()))
+                .Returns(new List<V1Pod> { pod });
+            var client = new ReverseProxyClient(_dockerMock.Object, _clientFunc, _consoleMock.Object, _kindMock.Object);
+
+            // Act
+            var result = InvokePatchCoreDns(client, clusterName);
+
+            // Assert
+            Assert.True(result);
+            _kubeClientMock.Verify(x => x.Update(It.Is<V1ConfigMap>(cm => cm.Data["Corefile"].Contains($"rewrite name {clusterName}.dev-k8s.cloud svc.ns.svc.cluster.local"))), Times.Once);
+            _kubeClientMock.Verify(x => x.Delete(pod), Times.Once);
+            _consoleMock.Verify(x => x.WriteLine(It.Is<string>(s => s.Contains("CoreDNS configmap updated successfully."))), Times.Once);
+        }
+
+        // Helper to invoke private PatchCoreDns via reflection
+        private static bool InvokePatchCoreDns(ReverseProxyClient client, string clusterName)
+        {
+            var method = typeof(ReverseProxyClient).GetMethod("PatchCoreDns", System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance);
+            return (bool)method.Invoke(client, new object[] { clusterName });
+        }
     }
 }