library/library_website/security/library_security.xml

<?xml version="1.0"?>
<odoo>
    <data noupdate="1">
        <record id="member_portal_rule" model="ir.rule">
            <field name="name">Library Member Portal Access</field>
            <field name="model_id" ref="library_member.model_library_member" />
            <field name="domain_force">
                [('user_id', '=', user.id)]
            </field>
            <field name="groups" eval="[(4,ref('base.group_portal'))]" />
        </record>

        <record id="checkout_portal_rule" model="ir.rule">
            <field name="name">Library Checkout Portal Access</field>
            <field name="model_id" ref="library_checkout.model_library_checkout" />
            <field name="domain_force">
                [('member_id.user_id', '=', user.id)]
            </field>
            <field name="groups" eval="[(4,ref('base.group_portal'))]" />
        </record>
    </data>
</odoo>