Added readme (#15)

Author: doubaokun

README.md

@@ -10,6 +10,14 @@ OpenSwoole is a programmatic platform building modernized systems with async IO,
 + __Discord__: <https://discord.gg/5QC57RNPpw>
 + __IDE Helper__: <https://github.com/openswoole/ide-helper>
 
+## Install
+
+You can add this package to your project using [Composer](https://getcomposer.org):
+
+```bash
+composer require openswoole/core
+```
+
 ## Documentation
 
 Documentation for Open Swoole can be found on the [Open Swoole website](https://openswoole.com/docs).

src/Coroutine/Client/PostgresClientFactory.php

@@ -0,0 +1,30 @@
+<?php
+
+declare(strict_types=1);
+/**
+ * This file is part of OpenSwoole.
+ * @link     https://openswoole.com
+ * @contact  [email protected]
+ */
+namespace OpenSwoole\Core\Coroutine\Client;
+
+use OpenSwoole\Client\Exception;
+use OpenSwoole\Coroutine\PostgreSQL;
+
+final class PostgresClientFactory implements ClientFactoryInterface
+{
+    /**
+     * @param mixed $config
+     * @throws Exception
+     */
+    public static function make($config)
+    {
+        if ($config instanceof PostgresConfig) {
+            $postgres = new PostgreSQL();
+            $postgres->connect($config->getConnectionString());
+            return $postgres;
+        }
+
+        throw new Exception('Wrong config used');
+    }
+}

src/Coroutine/Client/PostgresConfig.php

@@ -0,0 +1,91 @@
+<?php
+
+declare(strict_types=1);
+/**
+ * This file is part of OpenSwoole.
+ * @link     https://openswoole.com
+ * @contact  [email protected]
+ */
+namespace OpenSwoole\Core\Coroutine\Client;
+
+class PostgresConfig implements ClientConfigInterface
+{
+    /** @var string */
+    protected $host = '127.0.0.1';
+
+    /** @var int */
+    protected $port = 5432;
+
+    /** @var string */
+    protected $dbname = 'test';
+
+    /** @var string */
+    protected $username = 'postgres';
+
+    /** @var string */
+    protected $password = '';
+
+    public function getHost(): string
+    {
+        return $this->host;
+    }
+
+    public function withHost($host): self
+    {
+        $this->host = $host;
+        return $this;
+    }
+
+    public function getPort(): int
+    {
+        return $this->port;
+    }
+
+    public function withPort(int $port): self
+    {
+        $this->port = $port;
+        return $this;
+    }
+
+    public function getDbname(): string
+    {
+        return $this->dbname;
+    }
+
+    public function withDbname(string $dbname): self
+    {
+        $this->dbname = $dbname;
+        return $this;
+    }
+
+    public function getUsername(): string
+    {
+        return $this->username;
+    }
+
+    public function withUsername(string $username): self
+    {
+        $this->username = $username;
+        return $this;
+    }
+
+    public function getPassword(): string
+    {
+        return $this->password;
+    }
+
+    public function withPassword(string $password): self
+    {
+        $this->password = $password;
+        return $this;
+    }
+
+    public function getConnectionString(): string
+    {
+        return 'host=' . $this->host .
+            ';port=' . $this->port .
+            ';dbname=' . $this->dbname .
+            ';user=' . $this->username .
+            ';password=' . $this->password;
+    }
+}