src/go.chromium.org/chromiumos/test/util/helpers/helpers.go

// Copyright 2023 The ChromiumOS Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

package helpers

import (
	"go.chromium.org/chromiumos/test/execution/errors"
	"fmt"
	"io"
	"log"
	"os"
	"path/filepath"
)

// CreateLogFile creates a file and its parent directory for logging purpose.
func CreateLogFile(fullPath string) (*os.File, error) {
	if err := os.MkdirAll(fullPath, 0755); err != nil {
		return nil, errors.NewStatusError(errors.IOCreateError,
			fmt.Errorf("failed to create directory %v: %w", fullPath, err))
	}

	logFullPathName := filepath.Join(fullPath, "log.txt")

	// Log the full output of the command to disk.
	logFile, err := os.Create(logFullPathName)
	if err != nil {
		return nil, errors.NewStatusError(errors.IOCreateError,
			fmt.Errorf("failed to create file %v: %w", fullPath, err))
	}
	return logFile, nil
}

// NewLogger creates a logger. Using go default logger for now.
func NewLogger(logFile *os.File) *log.Logger {
	mw := io.MultiWriter(logFile, os.Stderr)
	return log.New(mw, "", log.LstdFlags|log.LUTC)
}