Fix kubectl tab-completion and improve error messages

Try to fix the following issues when `kubectl` is an alias for `minikube kubectl --` and tab-completion for `kubectl` is enabled: 1. When `--cluster name` form of command-line option is used, it conflicts with argument parsing, `name` is interpreted as plugin name. Call to `kubectl --cluster test help` leads to error `Error: flags cannot be placed before plugin name: --cluster`. Fix this by using `--cluster=name` form, which is correctly handled also in call `kubectl --cluster=test help`. 2. When `--cluster=name` is added as first argument (as seen in original code), it still leads to error mentioned above when the command is unknown like in the call `kubectl --cluster=test unknown`. Fix this by inserting `--cluster=name` after all (sub-)commands and before any flags/options. 3. The original code passed `--cluster=name` to normal `kubectl` calls, but omitted it for tab-completion calls. This might lead to wrong tab suggestions about pods, deployments and the like. Fix this by always adding `--cluster=name` option to the command line. 4. In case of tab-completion, put the `--cluster=name` immediately after `__complete` command to prevent any interference with incomplete commands (just in case). This works fine and does not generate any errors like mentioned in point 2.
kubernetes · Apr 8, 2023 · c662261 · c662261
1 parent 78d2885
commit c662261
Showing 1 changed file with 19 additions and 3 deletions.
diff --git a/cmd/minikube/cmd/kubectl.go b/cmd/minikube/cmd/kubectl.go
@@ -21,6 +21,7 @@ import (
 	"os"
 	"os/exec"
 	"path"
+	"strings"
 	"syscall"
 
 	"github.com/spf13/cobra"
@@ -96,9 +97,24 @@ host. Please be aware that when using --ssh all paths will apply to the remote m
 			os.Exit(1)
 		}
 
-		if len(args) > 1 && args[0] != "--help" && args[0] != cobra.ShellCompRequestCmd {
-			cluster := []string{"--cluster", cname}
-			args = append(cluster, args...)
+		if len(args) > 0 {
+			insertIndex := 0
+			if args[0] == cobra.ShellCompRequestCmd || args[0] == cobra.ShellCompNoDescRequestCmd {
+				// Insert right after __complete to allow code completion from the correct cluster.
+				insertIndex = 1
+			} else {
+				// Add cluster argument before first flag, but after all commands.
+				// This improves error message of kubectl in case the command is wrong.
+				insertIndex = len(args)
+				for i, arg := range args {
+					if strings.HasPrefix(arg, "-") {
+						insertIndex = i
+						break
+					}
+				}
+			}
+			clusterArg := "--cluster=" + cname
+			args = append(append(append([]string{}, args[:insertIndex]...), clusterArg), args[insertIndex:]...)
 		}
 
 		c, err := KubectlCommand(version, binaryMirror, args...)