Unable to connect to local PostgreSQL database - ruby-on-rails

Question

I created a simple rails application:
1
$ rails new myapp1 -d postrgresql
2. Removed /public/index.html
3. Created the Homecontroller and the actions
4. Wrote the routes
myapp1::Application.routes.draw do
root :to => "home#index"
match 'about' => 'home#about'
match 'contacts' => 'home#contacts'
match 'projects' => 'home#projects'
end
5. Created the views and the default layout
6. The bottom line. Here is the database.yml
development:
adapter: postgresql
encoding: unicode
database: myapp1_db
host: localhost
pool: 5
username: myapp1_user
password: 1234
test:
adapter: postgresql
encoding: unicode
database: myapp1_db
host: localhost
pool: 5
username: myapp1_user
password: 1234
production:
adapter: postgresql
encoding: unicode
database: myapp1_db
host: localhost
pool: 5
username: myapp1_user
password: 1234
and of course I created user and database
sudo -u postgres psql
postgres=# \password
postgres=# create user myapp1_user with password '1234';
postgres=# create database myapp1_db owner myapp1_user;
But there are some worries:
1. Now I don't use any database, but in spite of this the application gives an error
PG::Error FATAL: Peer authentication failed for user "myapp1"
2. It seems like rails turns a blind eye to database.yml. Why does it use the user myapp1 instead of myapp1_user?

Answer 1

Whitespace is significant in YAML.
production:
adapter: postgresql
encoding: unicode
...
password: 1234
Should be:
production:
adapter: postgresql
encoding: unicode
...
password: 1234

Answer 2

Provide host and port in the database.yml file, like this:
development:
adapter: postgresql
encoding: unicode
database: myapp1_db
host: localhost
pool: 5
username: myapp1_user
password: 1234
host: localhost
port: 5432
Works like a charm on Ubuntu 12.04 LTS with Rails 3.2.x and PostgreSQL 9.1.x