Re: question on row level security

On 30/12/2015 17:32, Joe Conway wrote:
> On 12/30/2015 08:58 AM, Tim Dudgeon wrote:
>> e.g. conceptually:
>>
>> set app_user 'john';
>> select * from foo;
>>
>> where the select * is restricted by a RLS check that includes 'john' as
>> the app_user.
>> Of course custom SQL could be generated for this, but it would be safer
>> if it could be handled using RLS.
>>
>> Any ways to do this?
> Something like this:
>
> 8<--------------------------
> CREATE USER application;
>
> CREATE TABLE t1 (id int primary key, f1 text, app_user text);
> INSERT INTO t1 VALUES(1,'a','bob');
> INSERT INTO t1 VALUES(2,'b','alice');
> ALTER TABLE t1 ENABLE ROW LEVEL SECURITY;
> CREATE POLICY P ON t1 USING (app_user =
> current_setting('app_name.app_user'));
> GRANT SELECT ON t1 TO application;
>
> SET SESSION AUTHORIZATION application;
>
> regression=> SET app_name.app_user = 'bob';
> SET
> regression=> SELECT * FROM t1;
>   id | f1 | app_user
> ----+----+----------
>    1 | a  | bob
> (1 row)
>
> regression=> SET app_name.app_user = 'alice';
> SET
> regression=> SELECT * FROM t1;
>   id | f1 | app_user
> ----+----+----------
>    2 | b  | alice
> (1 row)
>
> regression=> SET app_name.app_user = 'none';
> SET
> regression=> SELECT * FROM t1;
>   id | f1 | app_user
> ----+----+----------
> (0 rows)
>
> 8<--------------------------
>
> HTH,
>
> Joe
>
Looks like that's what I need.
I'll give it a try.

Thanks
Tim