library/log4php/appenders/LoggerAppenderPDO.php
changeset 0 4869aea77e21
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--- /dev/null
+++ b/library/log4php/appenders/LoggerAppenderPDO.php
@@ -0,0 +1,282 @@
+<?php
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * LoggerAppenderPDO appender logs to a database using the PHP's PDO extension.
+ *
+ * ## Configurable parameters: ##
+ *
+ * - dsn             - The Data Source Name (DSN) used to connect to the database.
+ * - user            - Username used to connect to the database.
+ * - password        - Password used to connect to the database.
+ * - table           - Name of the table to which log entries are be inserted.
+ * - insertSQL       - Sets the insert statement for a logging event. Defaults
+ *                     to the correct one - change only if you are sure what you are doing.
+ * - insertPattern   - The conversion pattern to use in conjuction with insert
+ *                     SQL. Must contain the same number of comma separated
+ *                     conversion patterns as there are question marks in the
+ *                     insertSQL.
+ *
+ * @version $Revision: 1374546 $
+ * @package log4php
+ * @subpackage appenders
+ * @since 2.0
+ * @license http://www.apache.org/licenses/LICENSE-2.0 Apache License, Version 2.0
+ * @link http://logging.apache.org/log4php/docs/appenders/pdo.html Appender documentation
+ */
+class LoggerAppenderPDO extends LoggerAppender {
+
+    // ******************************************
+    // *** Configurable parameters            ***
+    // ******************************************
+
+    /**
+     * DSN string used to connect to the database.
+     * @see http://www.php.net/manual/en/pdo.construct.php
+     */
+    protected $dsn;
+
+    /** Database user name. */
+    protected $user;
+
+    /** Database password. */
+    protected $password;
+
+    /**
+     * The insert query.
+     *
+     * The __TABLE__ placeholder will be replaced by the table name from
+     * {@link $table}.
+     *
+     * The questionmarks are part of the prepared statement, and they must
+     * match the number of conversion specifiers in {@link insertPattern}.
+     */
+    protected $insertSQL = "INSERT INTO __TABLE__ (timestamp, logger, level, message, thread, file, line) VALUES (?, ?, ?, ?, ?, ?, ?)";
+
+    /**
+     * A comma separated list of {@link LoggerPatternLayout} format strings
+     * which replace the "?" in {@link $insertSQL}.
+     *
+     * Must contain the same number of comma separated conversion patterns as
+     * there are question marks in {@link insertSQL}.
+     *
+     * @see LoggerPatternLayout For conversion patterns.
+     */
+    protected $insertPattern = "%date{Y-m-d H:i:s},%logger,%level,%message,%pid,%file,%line";
+
+    /** Name of the table to which to append log events. */
+    protected $table = 'log4php_log';
+
+    /** The number of recconect attempts to make on failed append. */
+    protected $reconnectAttempts = 3;
+
+
+    // ******************************************
+    // *** Private memebers                   ***
+    // ******************************************
+
+    /**
+     * The PDO instance.
+     * @var PDO
+     */
+    protected $db;
+
+    /**
+     * Prepared statement for the insert query.
+     * @var PDOStatement
+     */
+    protected $preparedInsert;
+
+    /** This appender does not require a layout. */
+    protected $requiresLayout = false;
+
+
+    // ******************************************
+    // *** Appender methods                   ***
+    // ******************************************
+
+    /**
+     * Acquires a database connection based on parameters.
+     * Parses the insert pattern to create a chain of converters which will be
+     * used in forming query parameters from logging events.
+     */
+    public function activateOptions() {
+        try {
+            $this->establishConnection();
+        } catch (PDOException $e) {
+            $this->warn("Failed connecting to database. Closing appender. Error: " . $e->getMessage());
+            $this->close();
+            return;
+        }
+
+        // Parse the insert patterns; pattern parts are comma delimited
+        $pieces = explode(',', $this->insertPattern);
+        $converterMap = LoggerLayoutPattern::getDefaultConverterMap();
+        foreach ($pieces as $pattern) {
+            $parser = new LoggerPatternParser($pattern, $converterMap);
+            $this->converters[] = $parser->parse();
+        }
+
+        $this->closed = false;
+    }
+
+    /**
+     * Connects to the database, and prepares the insert query.
+     * @throws PDOException If connect or prepare fails.
+     */
+    protected function establishConnection() {
+        // Acquire database connection
+        $this->db = new PDO($this->dsn, $this->user, $this->password);
+        $this->db->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
+
+        // Prepare the insert statement
+        $insertSQL = str_replace('__TABLE__', $this->table, $this->insertSQL);
+        $this->preparedInsert = $this->db->prepare($insertSQL);
+    }
+
+    /**
+     * Appends a new event to the database.
+     *
+     * If writing to database fails, it will retry by re-establishing the
+     * connection up to $reconnectAttempts times. If writing still fails,
+     * the appender will close.
+     */
+    public function append(LoggerLoggingEvent $event) {
+
+        for ($attempt = 1; $attempt <= $this->reconnectAttempts + 1; $attempt++) {
+            try {
+                // Attempt to write to database
+                $this->preparedInsert->execute($this->format($event));
+                $this->preparedInsert->closeCursor();
+                break;
+            } catch (PDOException $e) {
+                $this->warn("Failed writing to database: " . $e->getMessage());
+
+                // Close the appender if it's the last attempt
+                if ($attempt > $this->reconnectAttempts) {
+                    $this->warn("Failed writing to database after {$this->reconnectAttempts} reconnect attempts. Closing appender.");
+                    $this->close();
+                    // Otherwise reconnect and try to write again
+                } else {
+                    $this->warn("Attempting a reconnect (attempt $attempt of {$this->reconnectAttempts}).");
+                    $this->establishConnection();
+                }
+            }
+        }
+    }
+
+    /**
+     * Converts the logging event to a series of database parameters by using
+     * the converter chain which was set up on activation.
+     */
+    protected function format(LoggerLoggingEvent $event) {
+        $params = array();
+        foreach ($this->converters as $converter) {
+            $buffer = '';
+            while ($converter !== null) {
+                $converter->format($buffer, $event);
+                $converter = $converter->next;
+            }
+            $params[] = $buffer;
+        }
+        return $params;
+    }
+
+    /**
+     * Closes the connection to the logging database
+     */
+    public function close() {
+        // Close the connection (if any)
+        $this->db = null;
+
+        // Close the appender
+        $this->closed = true;
+    }
+
+    // ******************************************
+    // *** Accessor methods                   ***
+    // ******************************************
+
+    /**
+     * Returns the active database handle or null if not established.
+     * @return PDO
+     */
+    public function getDatabaseHandle() {
+        return $this->db;
+    }
+
+    /** Sets the username. */
+    public function setUser($user) {
+        $this->setString('user', $user);
+    }
+
+    /** Returns the username. */
+    public function getUser($user) {
+        return $this->user;
+    }
+
+    /** Sets the password. */
+    public function setPassword($password) {
+        $this->setString('password', $password);
+    }
+
+    /** Returns the password. */
+    public function getPassword($password) {
+        return $this->password;
+    }
+
+    /** Sets the insert SQL. */
+    public function setInsertSQL($sql) {
+        $this->setString('insertSQL', $sql);
+    }
+
+    /** Returns the insert SQL. */
+    public function getInsertSQL($sql) {
+        return $this->insertSQL;
+    }
+
+    /** Sets the insert pattern. */
+    public function setInsertPattern($pattern) {
+        $this->setString('insertPattern', $pattern);
+    }
+
+    /** Returns the insert pattern. */
+    public function getInsertPattern($pattern) {
+        return $this->insertPattern;
+    }
+
+    /** Sets the table name. */
+    public function setTable($table) {
+        $this->setString('table', $table);
+    }
+
+    /** Returns the table name. */
+    public function getTable($table) {
+        return $this->table;
+    }
+
+    /** Sets the DSN string. */
+    public function setDSN($dsn) {
+        $this->setString('dsn', $dsn);
+    }
+
+    /** Returns the DSN string. */
+    public function getDSN($dsn) {
+        return $this->setString('dsn', $dsn);
+    }
+}