Add utility to ease working with databases without the use of Zend

refs #7163

library/Icinga/Web/Setup/DbTool.php

@@ -0,0 +1,158 @@
+<?php
+// {{{ICINGA_LICENSE_HEADER}}}
+// {{{ICINGA_LICENSE_HEADER}}}
+
+namespace Icinga\Web\Setup;
+
+use PDO;
+use PDOException;
+use Icinga\Exception\ConfigurationError;
+
+/**
+ * Utility class to ease working with databases when installing Icinga Web 2 or one of its modules
+ */
+class DbTool
+{
+    /**
+     * The database connection
+     *
+     * @var PDO
+     */
+    protected $conn;
+
+    /**
+     * The resource configuration
+     *
+     * @var array
+     */
+    protected $config;
+
+    /**
+     * Create a new DbTool
+     *
+     * @param   array   $config     The resource configuration to use
+     */
+    public function __construct(array $config)
+    {
+        $this->config = $config;
+    }
+
+    /**
+     * Connect to the server
+     */
+    public function connectToHost()
+    {
+        $this->assertHostAccess();
+        $this->connect();
+    }
+
+    /**
+     * Connect to the database
+     */
+    public function connectToDb()
+    {
+        $this->assertHostAccess();
+        $this->assertDatabaseAccess();
+        $this->connect($this->config['dbname']);
+    }
+
+    /**
+     * Assert that all configuration values exist that are required to connect to a server
+     *
+     * @throws  ConfigurationError
+     */
+    protected function assertHostAccess()
+    {
+        if (false === isset($this->config['db'])) {
+            throw new ConfigurationError('Can\'t connect to database server of unknown type');
+        } elseif (false === isset($this->config['host'])) {
+            throw new ConfigurationError('Can\'t connect to database server without a hostname or address');
+        } elseif (false === isset($this->config['port'])) {
+            throw new ConfigurationError('Can\'t connect to database server without a port');
+        } elseif (false === isset($this->config['username'])) {
+            throw new ConfigurationError('Can\'t connect to database server without a username');
+        } elseif (false === isset($this->config['password'])) {
+            throw new ConfigurationError('Can\'t connect to database server without a password');
+        }
+    }
+
+    /**
+     * Assert that all configuration values exist that are required to connect to a database
+     *
+     * @throws  ConfigurationError
+     */
+    protected function assertDatabaseAccess()
+    {
+        if (false === isset($this->config['dbname'])) {
+            throw new ConfigurationError('Can\'t connect to database without a valid database name');
+        }
+    }
+
+    /**
+     * Establish a connection with the database or just the server by omitting the database name
+     *
+     * @param   string  $dbname     The name of the database to connect to
+     */
+    public function connect($dbname = null)
+    {
+        if ($this->conn !== null) {
+            return;
+        }
+
+        $this->conn = new PDO(
+            $this->buildDsn($this->config['db'], $dbname),
+            $this->config['username'],
+            $this->config['password'],
+            array(PDO::ATTR_TIMEOUT => 1, PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION)
+        );
+    }
+
+    /**
+     * Return a datasource name for the given database type and name
+     *
+     * @param   string      $dbtype
+     * @param   string      $dbname
+     *
+     * @return  string
+     *
+     * @throws  ConfigurationError      In case the passed database type is not supported
+     */
+    protected function buildDsn($dbtype, $dbname = null)
+    {
+        if ($dbtype === 'mysql') {
+            return 'mysql:host=' . $this->config['host'] . ';port=' . $this->config['port']
+                . ($dbname !== null ? ';dbname=' . $dbname : '');
+        } elseif ($dbtype === 'pgsql') {
+            return 'pgsql:host=' . $this->config['host'] . ';port=' . $this->config['port']
+                . ($dbname !== null ? ';dbname=' . $dbname : '');
+        } else {
+            throw new ConfigurationError(
+                'Failed to build data source name. Unsupported PDO driver "%s"',
+                $dbtype
+            );
+        }
+    }
+
+    /**
+     * Try to connect to the server and throw an exception if this fails
+     *
+     * @throws  PDOException    In case an error occurs that does not indicate that authentication failed
+     */
+    public function checkConnectivity()
+    {
+        try {
+            $this->connectToHost();
+        } catch (PDOException $e) {
+            if ($this->config['db'] === 'mysql') {
+                $code = $e->getCode();
+                if ($code !== 1040 && $code !== 1045) {
+                    throw $e;
+                }
+            } elseif ($this->config['db'] === 'pgsql') {
+                if (strpos($e->getMessage(), $this->config['username']) === false) {
+                    throw $e;
+                }
+            }
+        }
+    }
+}