policy support in sql processor

[amitu]

User processors to find data, eg path, current user, query params, http method etc.

-- string id: 
$processor$: request-data



-- ftd.crud-policy is-arpita:
string current-user:
string  id:

body can be used to describe the policy.

this policy allows arpita to edit published blog posts.

by default all conditions are anded. If you want to or, wrap things inside a `--ftd.or-condition`.

-- ftd.condition: returns true
select $current-user::string == ‘arpita’;

-- ftd.condition: returns single row

select 1 from blog_post where id = $id::string and published = true;


— end: is-arpita



-- ftd.crud-policy is-staff:
condition: returns-single-row

select 1 from fastn_user where identity = $current_user::string and data -> staff = true;



-- res r:
$processor$: sql
$policy$: $is-arpita or $is-staff
id: $id

select * from ft_user where id = $id::string;