on insert rule with default value

My rule below does not insert the the same uuid value into the test_log
table as is created in the test table when I insert a new value.  I know
I've worked through this before, but I'm not remembering why this is.
What's a right way to do this?

create table test ( anid   uuid   not null   default encode( gen_random_bytes( 16 ), 'hex' )::uuid   primary key, value
 text
 
);

create table test_log ( anid   uuid, value   text, op   text, attime   timestamp with time zone
);

create rule test_rule_a as
on insert to test do ( insert into test_log ( anid, value, op, attime ) values ( new.anid, new.value, 'insert', now()
)
);

-- 
Ron Peterson
Network & Systems Administrator
Mount Holyoke College
http://www.mtholyoke.edu/~rpeterso