Support remote kind config ref

[nabuskey]

Currently the kind config supplied via the --kind-config flag can refer to local files only. It should be able to reference remote kind configs as well. This is useful when a stack needs a specific kind configuration. Currently users need to clone the repository to use such stacks. e.g. --kind-config https://github.com/stacks/kind.config

[cmoulliard]

So your idea is to do this:

• if the string passed to the flag kind-config starts with https:// then we parse the Url
• We download the URL under a temporary folder
• We replace the value of the field: NewBuildOptions.KindConfigPath with the new local path
• We create the kind cluster using the local kind config file

Something like

package main

import (
	"fmt"
	"github.com/spf13/cobra"
	_ "github.com/spf13/cobra"
	"os"
	"snowdrop.dev/my-controller/cmd/util"
	"strings"
)

func main() {
	var kindConfig string

	// Root command (base command for the CLI)
	var rootCmd = &cobra.Command{
		Use:   "app",
		Short: "A simple CLI app using Cobra",
		Long:  `This is a simple CLI application built with Cobra to demonstrate the "create" command.`,
	}

	// Create command
	var createCmd = &cobra.Command{
		Use:   "create",
		Short: "Create a cluster",
		Long:  `The "create" command allows you to create a kind cluster.`,
		Run: func(cmd *cobra.Command, args []string) {
			if kindConfig == "" {
				fmt.Println("Error: --kind-config flag is required")
				os.Exit(1)
			}

			if util.IsValidUrl(kindConfig) {
				tempDir, err := os.MkdirTemp("", "idpbuilder_tmp")
				if err != nil {
					fmt.Println(err)
				}
				defer os.RemoveAll(tempDir)

				kindConfigFile := strings.Join([]string{tempDir, "kind.config"}, "/")

				err = util.DownloadFile(kindConfigFile, kindConfig)
				if err != nil {
					fmt.Println("Error downloading file: ", err)
					return
				}
			}

			fmt.Printf("Creating resource with config: %s\n", kindConfig)
		},
	}

	// Add flags to the create command
	createCmd.Flags().StringVarP(&kindConfig, "kind-config", "k", "", "Path to the kind configuration file (required)")

	// Add create command to root command
	rootCmd.AddCommand(createCmd)

	// Execute the root command
	if err := rootCmd.Execute(); err != nil {
		fmt.Println(err)
		os.Exit(1)
	}
}

func DownloadFile(filepath string, url string) error {
	resp, err := http.Get(url)
	if err != nil {
		return err
	}
	defer resp.Body.Close()

	// Create the file
	out, err := os.Create(filepath)
	if err != nil {
		return err
	}
	defer out.Close()

	// Write the body to file
	_, err = io.Copy(out, resp.Body)
	return err
}

func IsValidUrl(toParse string) bool {
	_, err := url.ParseRequestURI(toParse)
	if err != nil {
		return false
	}

	u, err := url.Parse(toParse)
	if err != nil || u.Scheme == "" || u.Host == "" {
		return false
	}
	return true
}

Correct ? @nabuskey

[nabuskey]

We probably don't need to download it to a temp folder. I think we can do all that in-memory. Otherwise, yes that's inline with what I was thinking.

[cmoulliard]

I think we can do all that in-memory.

I don't think so as kind go lib expects to read a file - see: https://github.com/kubernetes-sigs/kind/blob/main/pkg/internal/apis/config/encoding/load.go#L31-L51