WordPress admin: How can I display existing admin sub-menu based on user's role - wordpress

Question

I require to show an existing sub-menu item of admin menu based on a specific user role. The role is general-travel-editor.
The actual menu layout is like this
Travel Settings
- General settings
- Advanced Settings
The above user role is supposed access only the "General Settings" sub-menu. So I want to display the menu for this type users as:
Travel Settings
- General settings
I tried add_menu_page( 'Travel Settings', 'Travel Settings', 'general-travel-editor', 'general-travel-editor'); but I don't have the option to add the URL of this page.
I am using a VIP plugin.
I need to deliver this by tonight but got stuck!
Somebody please advise how I can do this.
UPDATE
User role and capabilities defined in functions.php
function general_travel_user_capabilities() {
$travel_option_caps = array(
'publish_travel-options' => true,
'edit_travel-options' => true,
'edit_others_travel-options' => true,
'edit_travel-option' => true,
'read_travel-option' => true,
'delete_travel-options' => true,
'delete_travel-option' => true,
'read' => true
);
wpcom_vip_duplicate_role('subscriber', 'travel-option-editor', 'Travel Option Editor', $travel_option_caps);
$travel_option_caps = array(
'publish_travel-options',
'edit_travel-options',
'edit_others_travel-options',
'delete_travel-options',
'delete_others_travel-options',
'read_private_travel-options',
'edit_travel-option',
'delete_travel-option',
'read_travel-option'
);
wpcom_vip_add_role_caps('editor', $travel_option_caps);
wpcom_vip_add_role_caps('administrator', $travel_option_caps);
}
add_action('init', 'general_travel_user_capabilities');
Travel Settings:
function travel_setting_pages_init() {
$travel_settings = travel_create_settings_page(
'travel_settings_page',
'Global Travel Settings',
array(
'parent' => false,
'title' => 'Travel Settings',
'position' => '59.4815152342',
),
array(
'travel_theme_options' => array(
'title' => '',
'description' => 'Settings that affect all pages of the site',
'fields' => array(
'mytravel_root_url' => array(
'type' => 'url',
'label' => 'MyTravel Root URL',
'description' => 'The base url for all MyTravel App links',
'default' => 'http://myurl.com',
),
'travel_phone' => array(
'type' => 'text',
'label' => 'Support Phone Number U.S.',
'description' => 'In top left of all pages',
'default' => '800-610-6500',
),
'travel_phone_canada' => array(
'type' => 'text',
'label' => 'Support Phone Number Canada',
'description' => 'In top left of all pages',
'default' => '877-330-3321',
),
'travel_weather_text' => array(
'type' => 'text',
'label' => 'Alert Text',
'description' => 'Text for the alert on the home page. Required for the alert to be displayed.',
'default' => '',
),
'travel_weather_link' => array(
'type' => 'url',
'label' => 'Alert Link',
'description' => 'Link for the alert on the home page. Required for the alert to be displayed.',
'default' => '',
),
'travel_weather_start_date' => array(
'type' => 'date',
'label' => 'Alert Start Date',
'description' => 'Start date to display the alert on the home page. Optional.',
'default' => '',
),
'travel_weather_end_date' => array(
'type' => 'date',
'label' => 'Alert end Date',
'description' => 'End date to display the alert on the home page. Optional.',
'default' => '',
)
)
)
)
);
// Home Page Settings Sub-Page
$slide_color_options = array(
'orange-grunge' => 'Orange Grunge Pattern',
'orange-img1' => 'Orange Image: Truck Engine with Person',
'orange-img2' => 'Orange Image: Truck Top with Person',
'orange-img3' => 'Orange Image: Forklift',
'orange-trailers' => 'Orange Image: Truck Trailers',
'black-trails' => 'Black Image: Light Trails',
'dark-grey' => 'Grey Image: Hand',
'white' => 'White Image: Trucks in Dock',
'orange' => 'Orange (To be removed)',
'blue' => 'Blue (To be removed)',
'black' => 'Black (To be removed)'
);
$travel_home_settings = travel_create_settings_page(
'travel_home_settings_page',
'Home Page Settings',
array(
'parent' => 'travel_settings_page',
'title' => 'Home Page Settings',
),
array(
'travel_home_slideshow_settings' => array(
'title' => 'Home Slideshow Settings',
'description' => 'If image is not set, slide will not be shown.',
'fields' => array(
// Slide 1
'slide_color_1' => array(
'type' => 'radio',
'label' => 'Slide 1 Background Color',
'default' => 'orange',
'options' => $slide_color_options
),
'slide_image_1' => array(
'type' => 'media',
'label' => 'Slide 1 Image',
'description' => 'Transparent PNG # 911x375. See travel-home-marquee-template.psd',
),
'slide_heading_1' => array(
'type' => 'textarea',
'label' => 'Slide 1 Heading',
),
'slide_sub_heading_1' => array(
'type' => 'wysiwyg',
'label' => 'Slide 1 Sub-Heading',
),
)
),
'travel_home_mid_cta_settings' => array(
'title' => 'Middle CTA Settings',
'fields' => array(
'mid_cta_heading_1_1' => array(
'type' => 'text',
'label' => 'Middle CTA 1 - First Line',
),
)
),
'travel_home_lower_cta_settings' => array(
// first block
'title' => 'Lower CTA Settings',
'fields' => array(
'lower_cta_image_1' => array(
'type' => 'media',
'label' => 'Lower CTA 1 - Header Image',
'description' => 'Transparent PNG # 193x71. If set, overrides main heading text.',
),
)
)
)
);
}
add_action( 'init', 'travel_setting_pages_init' );
travel-option is a Custom Post Type so I could use it in caps array. When logging in with the said user role I can see the CPT menus are coming up nicely but how can I add this settings menu? I apologize for posting such a long code!

Answer 1

I will leave another answer here for anyone facing the same situation.
For me, I was creating a plugin and wanted to give it a role different than (Administrator)
I searched for the already existing wp roles and chose "Author" role. Roles are mentioned in this link
Here's how I added my menu =>
add_menu_page( 'Page Title', 'Menu title', 'upload_files', 'url slug', 'function name to be executed', $logo , 1 );
So you just have to replace the 'upload_files' with any other capability matching the selected role.

Answer 2

The add_submenu_page function - which you should use for "advanced settings" is defined like this:
add_submenu_page( string $parent_slug, string $page_title, string
$menu_title, string $capability, string $menu_slug, callable $function
= '' );
As you can see you can define a certain $capability for displaying your menu or submenu page.
You can either use a capability which is only available to admins like manage_options or you could even define a special capability like this:
$role = get_role( 'administrator' );
$role->add_cap( 'edit_advanced_travel_settings' );
https://codex.wordpress.org/Function_Reference/add_cap
If you do it correctly the advanced page should only be visible to users whom you have granted this capability.
Note: Within the custom admin page callback - for security reasons - you should also check if the current user has the required capability.
if(current_user_can('edit_advanced_travel_settings')) {
// display page
} else {
echo "Sorry advanced travel settings are not available to you.";
}