求助：使用CodeIgniter实现无需表单提交，周末自动查库发邮件

Hey there! I’ve built exactly this kind of scheduled automation with CodeIgniter before, so let’s break down how to make this work without any user-triggered actions like form submits or buttons.

Core Idea #

This requirement boils down to three key pieces:

• Scheduled Execution: Use server-side cron jobs (or Windows Task Scheduler) to run a script automatically on weekends.
• Database Check: Fetch and evaluate the target data you need from your database.
• Email Dispatch: Leverage CodeIgniter’s built-in Email library to send notifications based on your data check results.

Step 1: Build Core Functions in CodeIgniter #

First, let’s set up the foundational components within your CI app:

1.1 Configure Email Library

You can set email settings globally in application/config/email.php, or configure it dynamically in your controller. Here’s a quick dynamic setup example:

$this->load->library('email');

$config['protocol'] = 'smtp';
$config['smtp_host'] = 'your-smtp-host.com';
$config['smtp_port'] = 587;
$config['smtp_user'] = 'your-email@domain.com';
$config['smtp_pass'] = 'your-email-password';
$config['mailtype'] = 'html';
$config['charset'] = 'utf-8';

$this->email->initialize($config);

1.2 Database Query Logic

Create a model (e.g., Email_model.php) to handle your data fetching. For example, if you need to notify users with pending tasks:

class Email_model extends CI_Model {
    public function get_users_to_notify() {
        // Adjust this query to match your actual data requirements
        return $this->db->select('email, username')
                        ->from('users')
                        ->where('has_pending_tasks', 1)
                        ->where('last_weekend_notified !=', date('Y-m-d')) // Avoid same-day duplicates
                        ->get()
                        ->result();
    }
}

Step 2: Create a CLI-Only Controller Method #

We’ll make a controller that can only run via the command line (CLI) — this avoids web request timeouts and is the standard way to run scheduled tasks in CI.

Create application/controllers/Cron.php:

class Cron extends CI_Controller {
    public function __construct() {
        parent::__construct();
        // Block web browser access for security
        if (!$this->input->is_cli_request()) {
            show_404();
        }
        
        $this->load->model('Email_model');
        $this->load->library('email');
    }

    public function send_weekend_notifications() {
        // Check if today is Saturday (6) or Sunday (7)
        $current_day = date('N');
        if (!in_array($current_day, [6,7])) {
            log_message('info', 'Skipped: today is not a weekend');
            return;
        }

        // Fetch target users from database
        $users = $this->Email_model->get_users_to_notify();
        if (empty($users)) {
            log_message('info', 'No users need weekend notifications this week');
            return;
        }

        // Send emails to each user
        foreach ($users as $user) {
            $this->email->clear();
            $this->email->from('notifications@yourdomain.com', 'Weekly Reminder');
            $this->email->to($user->email);
            $this->email->subject('Your Weekend Task Reminder');
            
            $email_body = "Hi {$user->username},\n\nYou have pending tasks waiting for you. Take a moment to wrap them up before the weekend ends!\n\nBest,\nYour Team";
            $this->email->message($email_body);

            if ($this->email->send()) {
                // Update user's notification status to avoid duplicates
                $this->db->where('email', $user->email)
                         ->update('users', ['last_weekend_notified' => date('Y-m-d')]);
                log_message('info', "Notification sent to {$user->email}");
            } else {
                log_message('error', "Failed to send to {$user->email}: " . $this->email->print_debugger());
            }
        }
    }
}

Step 3: Set Up Server-Side Scheduled Task #

Now tell your server to run this script automatically on weekends.

For Linux/Unix Servers (Cron Job)

1. Open your crontab file with crontab -e
2. Add a line to run the script every Saturday and Sunday at 9 AM (adjust time as needed):

0 9 * * 6,7 php /absolute/path/to/your/codeigniter/index.php cron send_weekend_notifications

• Breakdown: 0 9 * * 6,7 means "9:00 AM, every day of the month, every month, on Saturday (6) and Sunday (7)".
• Replace /absolute/path/to/your/codeigniter with your CI project’s actual root folder path.

For Windows Servers (Task Scheduler)

1. Open Task Scheduler and create a new task.
2. Set the trigger to run weekly on Saturday and Sunday at your desired time.
3. Set the action to "Start a program", with the program/script as your PHP executable path (e.g., C:\php\php.exe), and add arguments:

C:\path\to\your\codeigniter\index.php cron send_weekend_notifications

Key Best Practices #

• CLI Restriction: The controller uses is_cli_request() to block web access, preventing unauthorized execution.
• Logging: Use CodeIgniter’s built-in log_message() to track runs, successes, and failures — critical for debugging.
• Avoid Duplicates: The last_weekend_notified field ensures you don’t send multiple emails to the same user in one weekend.
• Test Manually: Run the script via CLI first to catch issues: php /path/to/your/codeigniter/index.php cron send_weekend_notifications

内容的提问来源于stack exchange，提问作者Mia