my question too

Thank you for reply me  Neha Kakkar, but i already try this and it not work, it said psycopg2.extensions.cursor object has no attribute 'create_empty_db'. And i can't using self.env.cr cause also got error object has no attribute 'env'. Then i change it too request.env.cr and got error above. 

As far as i understand You can try these steps again,

In your module, add Python file controllers.py and add the necessary dependencies.

from odoo import http
from odoo.http import request

Create a class that inherits from http.Controller for your controller.

class AutoCreateDBController(http.Controller):

To specify the URL endpoint for your controller, add a route decorator.

@http.route('/auto_create_db', type='json', auth='none', methods=['POST'])

Create a method to manage the route, then enclose your code in it.

def create_database(self, db_name, admin_password):

    demo_data = False

    self.env.cr.create_empty_db(db_name)

    admin_user = self.env['res.users'].sudo().search([('login', '=', 'admin')], limit=1)

    admin_user.with_context(force_company=db_name).write({'password': admin_password})

Using self.env and self.env.cr, you can access the env and cr objects within the method, respectively.
Now you can invoke this controller by sending a POST request to the /auto_create_db URL endpoint and passing the db_name and admin_password as JSON data. 
I hope this helps you.