Transition Out of Postgres default user to a restricted user

[aecone]

Transitioning from the default postgres user to new users in a production environment involves a few steps to ensure security and maintain functionality. Here’s a structured approach to create new users and smoothly transition away from using the postgres user.
Steps to Create New Users and Transition

Identify the Required Permissions:
    Determine the specific permissions needed for different applications or users. This includes what actions they need to perform (e.g., SELECT, INSERT, UPDATE, DELETE) on various tables.

Create New Users:
    Use the CREATE USER command to create new users with specific passwords. Here’s an example:

    sql

CREATE USER app_user WITH PASSWORD 'secure_password';

Create a Database (if not already done):

If you haven’t created a dedicated database for your application, do so:

sql

CREATE DATABASE app_database;

Grant Privileges to the New Users:

Assign the necessary permissions to the new users for the specific database and tables they need to access. For example:

sql

GRANT CONNECT ON DATABASE app_database TO app_user;
GRANT USAGE ON SCHEMA public TO app_user;
GRANT SELECT, INSERT, UPDATE, DELETE ON ALL TABLES IN SCHEMA public TO app_user;

Transfer Ownership of Existing Objects (if needed):

If there are existing tables or other objects that need to be accessed by the new user, consider transferring ownership:

sql

ALTER TABLE your_table_name OWNER TO app_user;

Test the New User:

Connect to the database using the new user credentials to ensure that everything works as expected:

bash

psql -U app_user -d app_database

Update Your Applications:

Update your application configuration to use the new user’s credentials instead of the postgres user. Ensure that connection strings reflect the new username and password.

Monitor for Issues:

After transitioning, monitor the application for any issues related to permissions or access. Adjust user privileges as necessary.

Disable the Default User (optional):

Once you’re confident that everything is functioning correctly with the new users, you may consider disabling the default postgres user to enhance security:

sql

ALTER USER postgres WITH NOLOGIN;

Note: If you disable it, ensure you have at least one other superuser for emergency access.