Fix: Change DefaultAPIHost from 0.0.0.0 to 127.0.0.1

pkg/client/kubeconfig.go

@@ -162,6 +162,10 @@ func KubeconfigGet(ctx context.Context, runtime runtimes.Runtime, cluster *k3d.C
 	}
 
 	// update the server URL
+	// Replace 0.0.0.0 with 127.0.0.1 in the kubeconfig, as 0.0.0.0 is not a valid address for clients to connect to
+	if APIHost == k3d.DefaultAPIHost {
+		APIHost = "127.0.0.1"
+	}
 	kc.Clusters["default"].Server = fmt.Sprintf("https://%s:%s", APIHost, APIPort)
 
 	// rename user from default to admin

pkg/client/kubeconfig_test.go

@@ -0,0 +1,83 @@
+/*
+Copyright © 2020-2023 The k3d Author(s)
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+package client
+
+import (
+	"testing"
+
+	k3d "github.com/k3d-io/k3d/v5/pkg/types"
+)
+
+func TestAPIHostReplacement(t *testing.T) {
+	tests := []struct {
+		name            string
+		inputHost       string
+		expectedHost    string
+		shouldBeChanged bool
+	}{
+		{
+			name:            "0.0.0.0 should be replaced with 127.0.0.1",
+			inputHost:       "0.0.0.0",
+			expectedHost:    "127.0.0.1",
+			shouldBeChanged: true,
+		},
+		{
+			name:            "127.0.0.1 should remain unchanged",
+			inputHost:       "127.0.0.1",
+			expectedHost:    "127.0.0.1",
+			shouldBeChanged: false,
+		},
+		{
+			name:            "localhost should remain unchanged",
+			inputHost:       "localhost",
+			expectedHost:    "localhost",
+			shouldBeChanged: false,
+		},
+		{
+			name:            "custom IP should remain unchanged",
+			inputHost:       "192.168.1.100",
+			expectedHost:    "192.168.1.100",
+			shouldBeChanged: false,
+		},
+		{
+			name:            "hostname should remain unchanged",
+			inputHost:       "my-server.example.com",
+			expectedHost:    "my-server.example.com",
+			shouldBeChanged: false,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			apiHost := tt.inputHost
+			// This is the logic from KubeconfigGet that replaces 0.0.0.0 with 127.0.0.1
+			if apiHost == k3d.DefaultAPIHost {
+				apiHost = "127.0.0.1"
+			}
+
+			if apiHost != tt.expectedHost {
+				t.Errorf("Expected API host to be '%s', but got '%s'", tt.expectedHost, apiHost)
+			}
+		})
+	}
+}