Confusion over Postgres usernames/passwords/databasenames

Rails
1

I have a Ruby script
(https://github.com/jhsu802701/bsf-scrape/blob/master/scrape.rb) that
scrapes web pages and stores the results in a Postgres database. I’m
trying to set this up not only in the development environment but in a
production environment as well, and the production environment is giving
me
authentication errors.

I’m confused over the names and passwords. There are:
1A. Local machine (user1A and password1A): used for logging in when I
boot
up Linux, owner of the Ruby script
1B. Local Postgres (user1B and password1B): the username and password
for
PostSQL
1C. Name of the local Postgres database (db1C)
2A. Web host SSH (user2A and password 2A): the username and password
for
connecting to the production environment through SSH
2B. Web host Postgres (user2B and password 2B): the username and
password
2C. Name of the remote Postgres database (db1C)

The script has a class called FundDatabase.

A password needs to be specified in the conn function within the
FundDatabase class:
def connect
@conn = PG.connect(
:dbname => $db_name,
:user => $db_user,
:password => $db_password)
end

I keep getting confused. My questions:

  1. When I create a local superuser (user1B) with the command “CREATE
    ROLE
    [local username] SUPERUSER LOGIN;”, why don’t I need to provide a
    password
    (password1B) specific to this user?
  2. In order to get my script to run, user1B must be the same as user1A,
    or
    I get an authentication error. Am I correct in using the same usernames
    both for my local machine and the local Postgres database?
  3. In the @conn function in my script in the production environment, am
    I
    supposed to use my SSH login (user2A) and password (password2A)? Or am
    I
    supposed to use my database login (user2B) and password (password2B)?
    Do
    user2A and user2B need to be one and the same (just like user1A and
    user1B)?
2

On Apr 4, 2013, at 7:32 AM, Jason H., Android developer wrote:

The script has a class called FundDatabase.

  1. When I create a local superuser (user1B) with the command “CREATE ROLE
    [local username] SUPERUSER LOGIN;”, why don’t I need to provide a password
    (password1B) specific to this user?
  2. In order to get my script to run, user1B must be the same as user1A, or I
    get an authentication error. Am I correct in using the same usernames both for my
    local machine and the local Postgres database?
  3. In the @conn function in my script in the production environment, am I
    supposed to use my SSH login (user2A) and password (password2A)? Or am I supposed
    to use my database login (user2B) and password (password2B)? Do user2A and user2B
    need to be one and the same (just like user1A and user1B)?

postgresql authentication is accomplished by a file called pg_hba.conf
on the server itself and you should located that file, make any changes
you need to make and restart the postgresql server to implement.

One the user can connect, the actual users (or groups) must have
assigned permissions to read, write to the particular database within
postgres itself.

Craig