Enhancement: a check for MySQL connections

Related: easybib/issues#4396

Author: till

src/ZendDiagnostics/Check/MySQLCheck.php

@@ -0,0 +1,81 @@
+<?php
+/**
+ * @license   http://framework.zend.com/license/new-bsd New BSD License
+ */
+
+namespace ZendDiagnostics\Check;
+
+use PDO;
+use ZendDiagnostics\Result;
+
+/**
+ * Ensures a connection to the MySQL server/database is possible.
+ */
+class MySQLCheck implements CheckInterface
+{
+    private $dbname;
+    private $host;
+    private $passwd;
+    private $port;
+    private $username;
+
+    /**
+     * @param string $host
+     * @param string $username
+     * @param string $passwd
+     * @param string $dbname
+     * @param int $port
+     *
+     * @return self
+     */
+    public function __construct($host, $username, $passwd, $dbname, $port = 3306)
+    {
+        $this->host = $host;
+        $this->username = $username;
+        $this->passwd = $passwd;
+        $this->dbname = $dbname;
+        $this->port = $port;
+    }
+
+    /**
+     * @return Result\Failure|Result\Success
+     */
+    public function check()
+    {
+        $dsn = sprintf(
+            'mysql:host=%s;dbname=%s;charset=utf8;port=%d',
+            $this->host,
+            $this->dbname,
+            $this->port
+        );
+
+        $msg = 'Could not talk to mysql';
+
+        try {
+            $pdo = new PDO(
+                $dsn,
+                $this->username,
+                $this->passwd
+            );
+            $pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
+            $pdo->setAttribute(PDO::ATTR_TIMEOUT, 1); // 1 second timeout
+            $status = $pdo->getAttribute(PDO::ATTR_CONNECTION_STATUS);
+            if (null !== $status) {
+                return new Result\Success('Can haz MySQL');
+            }
+        } catch (\PDOException $e) {
+            // skip to failure
+            $msg .= ', e: ' . $e->getCode();
+        }
+
+        return new Result\Failure($msg);
+    }
+
+    /**
+     * @return string
+     */
+    public function getLabel()
+    {
+        return 'Check if MySQL can be reached';
+    }
+}