Connect to postgresql server on amazon ec2 (Linux AMI) from PHP - php

Question

I started an amazon ec2 instance (Linux AMI) , and installed postgresql 9.2.15 over it. I then went to the Security Group: mygroup-1 and opened the 5432 TCP Port:
Ports Protocol Source mygroup-1
80 tcp 0.0.0.0/0 ✔
5432 tcp 0.0.0.0/0 ✔
22 tcp 0.0.0.0/0 ✔
3389 tcp 0.0.0.0/0 ✔
443 tcp 0.0.0.0/0 ✔
I have created a database and user.
My /var/lib/pgsql9/data/pg_hba.conf looks like this:
# TYPE DATABASE USER ADDRESS METHOD
# "local" is for Unix domain socket connections only
local all all trust
# IPv4 local connections:
host all all 127.0.0.1/32 ident
host all all 0.0.0.0/0 md5
# IPv6 local connections:
host all all ::1/128 ident
# Allow replication connections from localhost, by a user with the
# replication privilege.
#local replication postgres trust
#host replication postgres 127.0.0.1/32 ident
#host replication postgres ::1/128 ident
and /var/lib/pgsql9/data/postgresql.conf looks like this:
# - Connection Settings -
listen_addresses = '*' # what IP address(es) to listen on;
# comma-separated list of addresses;
# defaults to 'localhost', '*' = all
# (change requires restart)
port = 5432 # (change requires restart)
from the local computer, I have successfully connected to the ec2 postgresql using pgAdmin 3 program with connection information:
host: Public IP of EC2 running
port: 5432
username: my-postgresql-user
password: my-postgresql-pass
But when I try to connect to postgresql from my website using PHP (my website placed in the path /var/www/html/mysite), it can't connect.
My code:
$host = "Public IP of EC2 running";
$port = "5432";
$name = "my-postgresql-database";
$user = "my-postgresql-user";
$pass = "my-postgresql-pass";
$connstr = "host=$host port=$port dbname=$database_name user=$user password=$pass";
pg_connect($connstr);
when I run on local computer, it is connected ok, but when uploaded to /var/www/html/mysite, it can't connect to database.
I tried replacing the variables $host = "localhost" or "Public DNS of EC2 running" but still can't connect.
Please help