Function resolveAnswerModuleReplacement

internal/cli/build.go:257–301

resolveAnswerModuleReplacement resolves the ANSWER_MODULE value to a usable local path or remote replacement string. For v2+ versioned module paths (e.g. github.com/apache/answer@v2.0.0), Go module system rejects the version because the module path has no /v2 suffix. In that case the repository is c

(replacement, tmpDir string)

// Go module system rejects the version because the module path has no /v2 suffix. In that case
// the repository is cloned locally and the local path is returned instead.
func resolveAnswerModuleReplacement(replacement, tmpDir string) (string, error) {
	// Local paths can be used as-is.
	if strings.HasPrefix(replacement, "/") || strings.HasPrefix(replacement, "./") || strings.HasPrefix(replacement, "../") {
		return replacement, nil
	}

	// Parse module@version format.
	moduleName, version, hasVersion := strings.Cut(replacement, "@")
	if !hasVersion {
		return replacement, nil
	}

	// Only handle v2+ versions on module paths without the /vN suffix.
	ver, err := semver.StrictNewVersion(strings.TrimPrefix(version, "v"))
	if err != nil || ver.Major() < 2 {
		return replacement, nil
	}
	if strings.HasSuffix(moduleName, fmt.Sprintf("/v%d", ver.Major())) {
		return replacement, nil
	}

	// Clone the repo to a local directory and return its path.
	gitURL := "https://" + moduleName
	tag := "v" + strings.TrimPrefix(version, "v")
	localPath := filepath.Join(filepath.Dir(tmpDir), fmt.Sprintf("answer_src_%s", strings.ReplaceAll(version, ".", "_")))

	if _, statErr := os.Stat(localPath); statErr == nil {
		fmt.Printf("[build] using cached local clone at %s\n", localPath)
		return localPath, nil
	}

	fmt.Printf("[build] v2+ module detected, cloning %s@%s to local path %s...\n", moduleName, version, localPath)
	cloneCmd := exec.Command("git", "clone", "--depth=1", "--branch="+tag, gitURL, localPath)
	cloneCmd.Stdout = os.Stdout
	cloneCmd.Stderr = os.Stderr
	if err = cloneCmd.Run(); err != nil {
		return "", fmt.Errorf(
			"failed to clone %s@%s: %w\nTip: set ANSWER_MODULE to a local checkout path instead, e.g. ANSWER_MODULE=/path/to/answer",
			moduleName, version, err,
		)
	}

	fmt.Printf("[build] successfully cloned to %s\n", localPath)
	return localPath, nil
}

// movePluginToVendor move plugin to vendor dir
// Traverse the plugins, and if the plugin path is not github.com/apache/answer-plugins, move the contents of the current plugin to the vendor/github.com/apache/answer-plugins/ directory.