PHP Warning for no apparent reason!

I want to make a simple connection to the database but every time I test it, after a long loading of the page it generates a Warning.

File bank.class.php:

<?php
abstract class banco
{
    public $servidor = "localhost";
    public $usuario = "postgres";
    public $porta = 80;
    public $senha = "senha5";
    public $nomebanco = "wmma";
    public $conexao = NULL;
    public $dataset = NULL;
    public $linhasafetadas = -1;

    public function __construct()
    {
        $this->conecta();
    }
    public function __destruct()
    {
        if($this->conexao != NULL){
            pg_close($this->conexao);
        }
    }

    public function conecta()
    {
        $this->conexao = pg_connect($this->servidor, $this->porta, $this->nomebanco, $this->usuario, $this->senha);
        echo "Método Conecta foi chamado corretamente" . $this->conexao;
    }

Test.class.php file:

<?php
require_once("banco.class.php");
class teste extends banco
{

}

Test.php file:

require_once("classes/teste.class.php");
$testando = new teste();

As a result I have the following:

  

Warning: pg_connect (): Unable to connect to PostgreSQL server: server   closed the connection unexpectedly This probaly means the server   terminated abnormally before or while processing the request. in ...   bank.class.php on line 37

I have already restarted apache and postgres, I thought it could be an insistence on the connection, but it did not solve.