sql - Grant privileges on future tables in PostgreSQL?

Question

I am running PostgreSQL 9.3.1. I have test database and backup user which is used to backup the database. I have no problems with granting privileges to all current tables, but I have to grant privileges each time the new table is added to schema.

createdb test

psql test
test=# create table foo();
CREATE TABLE
test=# grant all on all tables in schema public to backup;
GRANT
test=# create table bar();
CREATE TABLE

psql -U backup test
test=> select * from foo;
test=> select * from bar;
ERROR:  permission denied for relation bar

Is it possible to grant access to tables which will be created in future without making user owner of the table?

Answer 1

It looks like the solution is to alter default privileges for backup user:

alter default privileges in schema public grant all on tables to backup;
alter default privileges in schema public grant all on sequences to backup;

From the comment by Matt Schaffer:

As caveat, the default only applies to the user that executed the alter statement. This confused me since I was driving most of my permissions statements from the postgres user but creating tables from an app user. In short, you might need something like this depending on your setup:

ALTER DEFAULT PRIVILEGES FOR USER webapp IN SCHEMA public GRANT SELECT ON SEQUENCES TO backup;
ALTER DEFAULT PRIVILEGES FOR USER webapp IN SCHEMA public GRANT SELECT ON TABLES TO backup;