Debug Mode

When troubleshooting issues with OneTap Login, enabling debug mode helps identify the root cause. This guide covers how to enable logging and interpret debug information.

WordPress Debug Mode

Enabling WP_DEBUG

Edit your wp-config.php file (in WordPress root):

// Enable WordPress debug mode
define('WP_DEBUG', true);

// Log errors to file instead of displaying
define('WP_DEBUG_LOG', true);

// Don't display errors on screen (for production)
define('WP_DEBUG_DISPLAY', false);

// Log database errors
define('SAVEQUERIES', true);

Log File Location

Debug messages are written to:

/wp-content/debug.log

Viewing the Log

Via FTP/SFTP:

Download: wp-content/debug.log
Open in text editor

Via SSH:

# View last 100 lines
tail -100 /path/to/wordpress/wp-content/debug.log

# Follow log in real-time
tail -f /path/to/wordpress/wp-content/debug.log

# Search for OneTap entries
grep -i "onetap" /path/to/wordpress/wp-content/debug.log

Via WordPress Plugin:

• Install "WP Debugging" plugin
• View logs from admin panel

OneTap Log Messages

Log Format

OneTap prefixes its log messages:

[04-Jan-2024 10:23:45 UTC] [ONETAP] Message here

Common Log Messages

Successful Authentication

[ONETAP] Token received for authentication
[ONETAP] Token validated successfully for: user@example.com
[ONETAP] User found by email: user@example.com (ID: 123)
[ONETAP] User logged in successfully: 123
[ONETAP] Redirect to: https://example.com/my-account/

New User Registration

[ONETAP] Token validated successfully for: newuser@example.com
[ONETAP] No existing user found, creating new user
[ONETAP] User created with ID: 456
[ONETAP] Role assigned: customer
[ONETAP] Google ID linked: 117895234567890123456

Error Messages

[ONETAP] ERROR: Token validation failed - Invalid audience
[ONETAP] ERROR: Rate limit exceeded for IP: 192.168.1.100
[ONETAP] ERROR: Forbidden role requested: administrator
[ONETAP] ERROR: User creation failed: Email already exists
[ONETAP] ERROR: Webhook delivery failed: HTTP 500

Interpreting Log Messages

Message	Meaning	Action
Token validated successfully	Google auth worked	Good
Invalid audience	Wrong Client ID	Check settings
Rate limit exceeded	Too many requests	Wait or whitelist
Forbidden role requested	Security triggered	Expected behavior
User creation failed	DB or validation issue	Check details

Browser Console Debugging

Opening Developer Tools

Browser	Shortcut
Chrome	F12 or Ctrl+Shift+I
Firefox	F12 or Ctrl+Shift+I
Safari	Cmd+Opt+I
Edge	F12 or Ctrl+Shift+I

Console Tab

Look for:

• Red errors: Critical issues
• Yellow warnings: Potential problems
• [GSI_LOGGER]: Google Identity Services messages

Common Console Messages

Normal/Informational:

[GSI_LOGGER]: OneTap initialized successfully
[GSI_LOGGER]: FedCM get status: OK

Errors:

[GSI_LOGGER]: Invalid origin for client: YOUR_CLIENT_ID
[GSI_LOGGER]: Missing required parameter: client_id

Network Tab

To see OAuth requests:

1. Open Network tab
2. Filter by "google" or "oauth"
3. Look for failed requests (red)
4. Click to see request/response details

JavaScript Debugging

Enable OneTap Debug Mode

Add to your theme's functions.php temporarily:

add_action('wp_footer', function() {
    ?>
    <script>
    // Log Google Identity Services events
    window.onGoogleLibraryLoad = function() {
        console.log('Google Identity Services loaded');
    };

    // Log OneTap events
    document.addEventListener('onetap_initialized', function(e) {
        console.log('OneTap initialized', e.detail);
    });

    document.addEventListener('onetap_success', function(e) {
        console.log('OneTap success', e.detail);
    });

    document.addEventListener('onetap_error', function(e) {
        console.log('OneTap error', e.detail);
    });
    </script>
    <?php
});

Check Script Loading

In browser console:

// Check if Google library loaded
console.log(typeof google !== 'undefined' ? 'Loaded' : 'Not loaded');

// Check if OneTap initialized
console.log(window.onetapInitialized);

REST API Debugging

Test Endpoint Directly

Test callback endpoint:

curl -v "https://yourdomain.com/wp-json/onetap/v1/test"

Expected response:

{"status":"ok","message":"OneTap endpoint is accessible"}

Check REST API Access

# Test general REST API
curl "https://yourdomain.com/wp-json/"

# Should return JSON with available routes

Debug REST Requests

In WordPress, add temporarily:

add_filter('rest_pre_dispatch', function($result, $server, $request) {
    if (strpos($request->get_route(), 'onetap') !== false) {
        error_log('[ONETAP REST] Route: ' . $request->get_route());
        error_log('[ONETAP REST] Method: ' . $request->get_method());
        error_log('[ONETAP REST] Params: ' . print_r($request->get_params(), true));
    }
    return $result;
}, 10, 3);

Database Debugging

Check User Meta

-- Find OneTap-related user meta
SELECT user_id, meta_key, meta_value
FROM wp_usermeta
WHERE meta_key LIKE '%onetap%'
   OR meta_key LIKE '%google%';

Check Options

-- Find OneTap settings
SELECT option_name, option_value
FROM wp_options
WHERE option_name LIKE '%onetap%';

Via WP-CLI

# Get OneTap settings
wp option get onetap_settings --format=json

# Get user's Google ID
wp user meta get 123 _onetap_google_id

Query Monitor Plugin

Installation

1. Install "Query Monitor" from WordPress.org
2. Activate
3. Look for "Query Monitor" in admin bar

What to Check

• PHP Errors: Any errors during request
• HTTP API Calls: External requests to Google
• Database Queries: SQL queries made
• Hooks & Actions: What hooks fired

OneTap-Specific Checks

Look for:

• Requests to oauth2.googleapis.com
• Requests to accounts.google.com
• Any failed HTTP requests

Email Debugging

Check Email Sending

If welcome emails aren't sending:

// Test email function
add_action('init', function() {
    if (isset($_GET['test_email'])) {
        $result = wp_mail(
            'your@email.com',
            'Test Email',
            'This is a test.'
        );
        var_dump($result);
        die();
    }
});

// Visit: yourdomain.com/?test_email=1

Log Emails

add_filter('wp_mail', function($args) {
    error_log('[EMAIL] To: ' . $args['to']);
    error_log('[EMAIL] Subject: ' . $args['subject']);
    return $args;
});

Webhook Debugging (PRO)

Log Webhook Deliveries

add_action('onetap_webhook_sent', function($url, $payload, $response) {
    error_log('[ONETAP WEBHOOK] URL: ' . $url);
    error_log('[ONETAP WEBHOOK] Payload: ' . json_encode($payload));
    error_log('[ONETAP WEBHOOK] Response: ' . print_r($response, true));
}, 10, 3);

Test Webhook Manually

# Test your webhook endpoint
curl -X POST https://your-webhook-url.com \
    -H "Content-Type: application/json" \
    -d '{"test": "data"}'

Creating a Debug Report

When contacting support, include:

1. Environment Information

// Add to functions.php temporarily
add_action('admin_notices', function() {
    if (current_user_can('manage_options')) {
        echo '<pre>';
        echo 'PHP: ' . phpversion() . "\n";
        echo 'WordPress: ' . get_bloginfo('version') . "\n";
        echo 'OneTap: ' . (defined('ONETAP_VERSION') ? ONETAP_VERSION : 'Unknown') . "\n";
        echo 'Theme: ' . wp_get_theme()->get('Name') . "\n";
        echo 'HTTPS: ' . (is_ssl() ? 'Yes' : 'No') . "\n";
        echo '</pre>';
    }
});

2. Recent Log Entries

# Get last 50 OneTap log entries
grep -i "onetap" wp-content/debug.log | tail -50

3. Active Plugins

Go to Plugins > Installed Plugins and note all active plugins.

4. Steps to Reproduce

1. Exact steps taken
2. Expected result
3. Actual result
4. Any error messages

Disabling Debug Mode

After troubleshooting, disable debug mode:

// wp-config.php
define('WP_DEBUG', false);
define('WP_DEBUG_LOG', false);
define('WP_DEBUG_DISPLAY', false);

Important: Don't leave debug mode enabled in production as it can:

• Expose sensitive information
• Slow down the site
• Fill up disk space with logs

Next Steps

• Common Issues - Specific solutions
• Error Codes - Error reference
• Support - Get help