main.go

package main

import (
	"fmt"
	"github.com/pmezard/go-difflib/difflib"
	"log"
	"os"
	"os/exec"
	"strings"
)

func main() {
	prohibitIndirectDepUpdate := os.Getenv("PROHIBIT_INDIRECT_DEP_UPDATE") == "true"

	// Read the original go.mod and go.sum files
	originalGoMod, err := os.ReadFile("go.mod")
	if err != nil {
		log.Fatalf("Failed to read go.mod: %v", err)
	}
	originalGoSum, err := os.ReadFile("go.sum")
	if err != nil {
		log.Fatalf("Failed to read go.sum: %v", err)
	}

	if prohibitIndirectDepUpdate {
		// Remove indirect lines
		lines := strings.Split(string(originalGoMod), "\n")
		var cleanedGoMod []string
		for _, line := range lines {
			if strings.HasSuffix(line, "// indirect") {
				continue
			}
			cleanedGoMod = append(cleanedGoMod, line)
		}
		err = os.WriteFile("go.mod", []byte(strings.Join(cleanedGoMod, "\n")), 0644)
		if err != nil {
			log.Fatalf("Failed to write cleaned go.mod: %v", err)
		}
	}

	// Run go mod tidy
	cmd := exec.Command("go", "mod", "tidy")
	cmd.Stdout = os.Stdout
	cmd.Stderr = os.Stderr
	err = cmd.Run()
	if err != nil {
		log.Fatalf("Failed to run go mod tidy: %v", err)
	}

	// Read
	updatedGoMod, err := os.ReadFile("go.mod")
	if err != nil {
		log.Fatalf("Failed to read updated go.mod: %v", err)
	}
	updatedGoSum, err := os.ReadFile("go.sum")
	if err != nil {
		log.Fatalf("Failed to read updated go.sum: %v", err)
	}
	// Compare the original and updated files
	if string(originalGoMod) != string(updatedGoMod) || string(originalGoSum) != string(updatedGoSum) {
		fmt.Println("go.mod or go.sum files have changed after running go mod tidy. Please commit the changes.")
		printDiff("go.mod", string(originalGoMod), string(updatedGoMod))
		printDiff("go.sum", string(originalGoSum), string(updatedGoSum))
		os.Exit(1)
	}

	fmt.Println("Go mod check action completed successfully.")
}

func printDiff(filename, originalContent, updatedContent string) {
	diff := difflib.UnifiedDiff{
		A:        difflib.SplitLines(originalContent),
		B:        difflib.SplitLines(updatedContent),
		FromFile: "Original",
		ToFile:   "Updated",
		Context:  3,
	}

	diffStr, err := difflib.GetUnifiedDiffString(diff)
	if err != nil {
		log.Fatalf("Failed to generate diff: %v", err)
	}

	if diffStr != "" {
		fmt.Printf("\nChanges detected in %s:\n\n%s\n", filename, diffStr)
	}
}