Connection by user with restricted access to pg_database

Hi!

We provide access for our customers to their databases. These
databases located on the same postgresql cluster, that's why we denied
access to pg_database, pg_roles and others to client's users.

One of our customer uses pg_admin. He can't connect to database by
provided username because there are no access to pg_database:

2015-12-15 15:33:18 ERROR : ERROR: permission denied for relation pg_database
2015-12-15 15:33:44 ERROR : Column not found in pgSet: "datlastsysoid"
2015-12-15 15:33:45 ERROR : Column not found in pgSet: datlastsysoid
2015-12-15 15:33:45 ERROR : Column not found in pgSet: oid
2015-12-15 15:33:46 ERROR : Column not found in pgSet: encoding
2015-12-15 15:33:47 ERROR : ERROR: permission denied for relation pg_user
2015-12-15 15:33:47 ERROR : Column not found in pgSet: usecreatedb
2015-12-15 15:33:48 ERROR : Column not found in pgSet: usesuper
2015-12-15 15:33:49 ERROR : Column not found in pgSet: upsince
2015-12-15 15:33:49 ERROR : Column not found in pgSet: confloadedsince
2015-12-15 15:33:50 ERROR : Column not found in pgSet: inrecovery
2015-12-15 15:33:50 ERROR : Column not found in pgSet: replayloc
2015-12-15 15:33:51 ERROR : Column not found in pgSet: receiveloc
2015-12-15 15:33:51 ERROR : Column not found in pgSet: replay_timestamp
2015-12-15 15:33:51 ERROR : Column not found in pgSet: isreplaypaused
2015-12-15 15:33:52 ERROR : ERROR: permission denied for relation pg_roles
2015-12-15 15:33:53 ERROR : Column not found in pgSet: rolcreatedb
2015-12-15 15:33:53 ERROR : Column not found in pgSet: rolcreaterole
2015-12-15 15:33:54 ERROR : ERROR: permission denied for relation pg_database
2015-12-15 15:33:55 ERROR : ERROR: permission denied for relation
pg_tablespace
2015-12-15 15:33:56 ERROR : ERROR: permission denied for relation pg_roles
2015-12-15 15:33:58 ERROR : ERROR: permission denied for relation pg_roles

pgAdmin version: 1.20.0
Postgresql version: 9.4.2
Postgresql OS: Ubuntu 12.04.3 Server
Client OS: Ubuntu desktop 14.10 x64

Does a workaround exist for this situation?

How to reproduce:

psql -d template1

REVOKE ALL ON DATABASE template1 FROM public;
REVOKE ALL ON SCHEMA public FROM public;
REVOKE ALL ON pg_user FROM public;
REVOKE ALL ON pg_roles FROM public;
REVOKE ALL ON pg_group FROM public;
REVOKE ALL ON pg_authid FROM public;
REVOKE ALL ON pg_auth_members FROM public;
REVOKE ALL ON pg_stat_activity FROM public;
REVOKE ALL ON pg_database FROM public;
REVOKE ALL ON pg_tablespace FROM public;
GRANT ALL ON SCHEMA public TO postgres;
CREATE DATABASE mydb;

psql -d mydb

REVOKE ALL ON DATABASE mydb FROM public;
CREATE ROLE myuser NOSUPERUSER NOCREATEDB NOCREATEROLE NOINHERIT LOGIN
ENCRYPTED PASSWORD '123';
GRANT USAGE ON SCHEMA public TO myuser;
GRANT CONNECT ON DATABASE mydb TO myuser;
ALTER DEFAULT PRIVILEGES FOR ROLE mydb IN SCHEMA public GRANT SELECT
ON TABLES to myuser;
GRANT SELECT ON ALL TABLES IN SCHEMA public TO myuserr;

Then connect with pgadmin, maintenance database: mydb, user: myuser.

--
Vladimir Yanchenko
Suport engineer
Naumen