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database2.php
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database2.php
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<?php
/**
* Database interface implementation
*
* This file is part of DokuWiki plugin database2 and is available under
* GPL version 2. See the following URL for a copy of this license!
*
* http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
*
*
* @author Thomas Urban <[email protected]>
* @version 0.2
* @copyright GPLv2
*
*/
if ( !defined( 'DB2_PATH' ) )
define( 'DB2_PATH', 'lib/plugins/database2/' );
/**
* Implementation of database access feature.
*
* This class is integrated into DokuWiki syntax extension in file syntax.php
* and provides the plugin's actual features like database interaction, table
* browsing, data lookup and input ...
*
* @author Thomas Urban <[email protected]>
* @version 0.2
* @copyright GPLv2
*
*/
class Database2
{
const maxSurroundingPagesCount = 3;
const maxUploadSize = 2097152; // 2 MiB
protected static $ioIndices = array();
/**
* Renderer for producing any output.
*
* @var Doku_Renderer_xhtml
*/
public $renderer;
/**
* Link to database of current namespace.
*
* @var PDO
*/
protected $db;
/**
* Name of driver indicating type of DB currently connected to.
*
* @var string
*/
private $driver;
/**
* Name of table managed by current instance.
*
* @var string
*/
protected $table = null;
/**
* Meta information on/definition of current table as provided in tag value
*
* @var array
*/
protected $meta = array();
/**
* Options additionally provided in opening tag's attributes.
*
* @var array
*/
protected $options = array();
/**
* I/O-Index assigned for use on acting on table managed by current
* instance.
*
* @var integer
*/
protected $ioIndex = null;
/**
* input data
*
* @var array
*/
private $input = null;
/**
* DSN used to connect to database server
*
* @var string
*/
private $dsn = null;
/**
* Name of slot in site configuration containing authentication data.
*
* @var string
*/
private $authSlot = null;
/**
* Reference to database syntax plugin object integrating this instance of
* Database2.
*
* @var DokuWiki_Syntax_Plugin
*/
protected $integrator = null;
/**
* Page ID explicitly selected to use in current instance.
*
* This is used to supercede ID returned by DokuWiki's getID() and is
* required in media.php using this class in a faked context.
*/
protected $explicitPageID = null;
public function __construct( Doku_Renderer $renderer,
DokuWiki_Syntax_Plugin $integrator )
{
$this->renderer = $renderer;
$this->db = null;
$this->integrator = $integrator;
$this->renderer->nocache();
}
/**
* Detects whether provided name is a valid name for a table or column.
*
* @param string $in name to test
* @return boolean true if provided name might be used for tables/columns
*/
public static function isValidName( $in )
{
return preg_match( '/^[_a-z][_a-z0-9]+$/i', $in );
}
/**
* Retrieves open link to current database file or null if not connected.
*
* @return PDO
*/
public function getLink()
{
return $this->db;
}
/**
* Retrieves configuration setting using integrator's interface.
*
* @param string $name name of setting to retrieve
* @return mixed retrieved configuration setting
*/
public function getConf( $name )
{
global $conf;
if ( $this->integrator instanceof DokuWiki_Syntax_Plugin )
{
$value = $this->integrator->getConf( $name, null );
if ( is_null( $value ) )
if ( !is_null( $conf[$name] ) )
$value = $conf[$name];
return $value;
}
// fix for accessing configuration in media.php
if ( isset( $conf['plugin']['database2'][$name] ) )
return $conf['plugin']['database2'][$name];
return $conf[$name];
}
/**
* Retrieves localized string.
*
* @param string $name name of localized string
* @return mixed retrieved localized string
*/
public function getLang( $name )
{
if ( $this->integrator instanceof DokuWiki_Syntax_Plugin )
return $this->integrator->getLang( $name );
// fix for accessing strings in media.php
if ( !is_array( $this->integrator ) )
{
$lang = array();
@include( dirname( __FILE__ ) . '/lang/en/lang.php' );
if ( $GLOBALS['conf']['lang'] != 'en' )
@include( dirname( __FILE__ ) . '/lang/' .
$GLOBALS['conf']['lang'] . '/lang.php' );
$this->integrator = $lang;
}
return $this->integrator[$name];
}
/**
* Retrieves index to be used for parameters/fields passed in I/O on
* currently processed integration of a table in current page.
*
* The current method is quite unstable, at least on editing arrangement
* of database2 instances in a page, however it should work in a production
* environment.
*
* @return integer numeric index
*/
protected function getIndex()
{
if ( is_null( $this->table ) )
throw new Exception( 'getIndex: missing name of managed table' );
if ( is_null( $this->ioIndex ) )
$this->ioIndex = self::$ioIndices[$tableName]++;
return $this->ioIndex;
}
/**
* Retrieves ID of current DokuWiki page.
*
* @return string
*/
protected function getPageID()
{
if ( !is_null( $this->explicitPageID ) )
return $this->explicitPageID;
return getID();
}
/**
* Allocates separate section in session data for state of current
* table instance.
*
* @return array
*/
protected function &getSession()
{
if ( !is_array( $_SESSION['database2'] ) )
$_SESSION['database2'] = array();
$id = $this->getPageID();
// if current page's source has changed ...
$dates = p_get_metadata( $id, 'date' );
if ( is_array( $_SESSION['database2'][$id] ) )
if ( $_SESSION['database2'][$id]['onRevision'] != $dates['modified'] )
// ... it's related session-based data is dropped
unset( $_SESSION['database2'][$id] );
if ( !is_array( $_SESSION['database2'][$id] ) )
$_SESSION['database2'][$id] = array(
'onRevision' => $dates['modified'],
'tables' => array(),
);
$index = $this->getIndex();
if ( !is_array( $_SESSION['database2'][$id]['tables'][$index] ) )
$_SESSION['database2'][$id]['tables'][$index] = array();
return $_SESSION['database2'][$id]['tables'][$index];
}
/**
* Allocates separate section in session data for temporary content of
* single-record editor.
*
* @return array
*/
protected function &getEditorSession()
{
$session =& $this->getSession();
if ( !is_array( $session['editors'] ) )
$session['editors'] = array();
return $session['editors'];
}
/**
* Renders provided HTML code replacing database tag in current Wiki page.
*
* @param string $code HTML code to render
*/
protected function render( $code )
{
$this->renderer->doc .= strval( $code );
}
/**
* Connects to database (external server, local SQLite DB file).
*
* @param string $dbPath database selector
* @param string $authConfigSlot name of slot in site config containing
* authentication data
* @return boolean true on success, false on failure
*/
public function connect( $dbPath, $authConfigSlot = null )
{
$dbPath = trim( $dbPath );
if ( $dbPath[0] == '@' )
$dsn = substr( $dbPath, 1 );
else if ( ( $dbPath[0] == '/' ) && !self::getConf( 'useslash' ) &&
is_dir( dirname( $dbPath ) ) &&
!preg_match( '#(\.\.)|(^\/(etc)\/)#', $dbPath ) )
$dsn = 'sqlite:' . $dbPath;
else
$dsn = 'sqlite:' . metaFN( $dbPath, '.db' );
try
{
// read username/password for authentication from optionally
// selected slot in site's configuration
if ( $authConfigSlot )
{
$username = $password = '';
foreach ( explode( "\n", $this->getConf( 'authSlots' ) ) as $line )
{
$line = trim( $line );
if ( ( $line[0] == '#' ) || ( ( $line[0] == '/' ) &&
( $line[1] == '/' ) ) || ( $line === '' ) )
// skip comments and empty lines
continue;
// parse assignment
$pos = 0;
$temp = self::parseAssignment( $line, $pos );
if ( !is_array( $temp ) )
continue;
list( $name, $value ) = $temp;
if ( strcasecmp( $name, $authConfigSlot ) )
// not related to current authentication slot
continue;
// split value into username and password
$value = trim( $value );
$sep = strcspn( $value, ':' );
$username = trim( substr( $value, 0, $sep ) );
$password = trim( substr( $value, $sep + 1 ) );
// done ...
break;
}
if ( $username === '' )
unset( $username, $password );
else if ( $password === '' )
unset( $password );
}
else
unset( $username, $password );
// connect to database
$this->db = new PDO( $dsn, $username, $password );
// request throwing exceptions on failure
$this->db->setAttribute( PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
// cache used driver name
$this->driver = strtolower( trim( $this->db->getAttribute(
PDO::ATTR_DRIVER_NAME ) ) );
if ( strpos( $this->driver, 'mysql' ) !== false )
// ensure to use proper encoding on talking to MySQL RDBMSs
// NOTE: according to server setup this may result in UTF-8 bytes
// being UTF-8 encoded, thus resulting in usual "garbage"
// TODO: add option for selecting whether using UTF8-mapping here
$this->db->query( 'SET NAMES UTF8' );
// store how to connect to database for integrated retrieval of files
$this->dsn = $dsn;
$this->authSlot = $authConfigSlot;
return true;
}
catch ( PDOException $e )
{
$this->render( sprintf( $this->getLang( 'nodblink' ), $e->getMessage() ) );
$this->db = $this->driver = null;
return false;
}
}
/**
* Reads all available input data extracting values related to this plugin.
*
* @return array set of input data related to current plugin
*/
protected function getInput()
{
if ( is_null( $this->input ) )
{
$index = $this->getIndex();
$this->input = array();
$matchingSecTok = ( $_REQUEST['sectok'] == getSecurityToken() );
foreach ( $_REQUEST as $name => $value )
if ( preg_match( '/^db2do(.+?)(_[xy])?$/i', $name, $matches ) )
if ( $matchingSecTok || ( $_GET[$name] && preg_match( '/^(cmd|opt)/i', $matches[1] ) ) )
if ( is_null( $this->input[$matches[1]] ) )
if ( !is_array( $value ) || !is_null( $value[$index] ) )
$this->input[$matches[1]] = is_array( $value ) ? $value[$index] : $value;
}
return $this->input;
}
/**
* Retrieves meta information on columns.
*
* @return array
*/
public function getColumnsMeta( $ignoreMissingMeta = false )
{
if ( !is_array( $this->meta ) || empty( $this->meta ) )
{
$session =& self::getSession();
if ( is_array( $session['definition'] ) )
$this->meta = $session['definition'];
else if ( $ignoreMissingMeta )
return array(); // don't store permanently ...
else
throw new Exception( $this->getLang( 'nocolmeta' ) );
}
return $this->meta;
}
/**
* Renders name of form element to conform with input parser above.
*
* @param string $name internal name of element
* @param index $rowid optional rowid element is related to
* @return string external name of form element
*/
protected function varname( $name, $rowid = null )
{
return 'db2do' . $name . ( $rowid ? $rowid : '' ) . '[' .
$this->getIndex() . ']';
}
/**
* Processes occurrence of database tag in a wiki page.
*
* The tag's value (stuff between opening and closing tag) is passed in
* $code.
*
* @param string $table name of table to work with
* @param string $code code found between opening and closing tag
* @param array $options additional options provided in tag attributes
*/
public function process( $table, $code, $options )
{
// wrap all action on database in one exception handler
try
{
// check whether or not database tags are enabled on this page
if ( !$this->getConf( 'enableallpages' ) )
{
$patterns = explode( "\n", trim( $this->getConf( 'enablepages' ) ) );
$enabled = false;
$pageID = $this->getPageID();
foreach ( $patterns as $pattern )
{
$pattern = trim( $pattern );
if ( preg_match( '#^/.+/\w*$#', $pattern ) )
$match = preg_match( $pattern, $pageID );
else
$match = fnmatch( $pattern, $pageID );
if ( $match )
{
$enabled = true;
break;
}
}
if ( !$enabled )
{
// use of database tag is disabled
$this->render( '<div class="database2-disabled">' .
$this->getLang( 'tagdisabled' ) . '</div>' );
return;
}
}
// normalize/validate table name
$table = preg_replace( '/[^\w]/', '_', trim( $table ) );
if ( in_array( $table, array( '__keys', '__locks', '__log', ) ) )
throw new Exception( $this->getLang( 'restabnames' ) );
$this->table = $table;
// select subset of input parameters
$this->ioIndex = null; // drop to re-obtain new I/O index next
$index = $this->getIndex(); // but ensure to obtain at all ...
// install set of options
$this->options = is_array( $options ) ? $options : array();
if ( trim( $this->options['mayview'] ) === '' )
$this->options['mayview'] = '@ALL';
if ( trim( $this->options['mayinspect'] ) === '' )
$this->options['mayinspect'] = '@ALL';
$this->options['view'] = trim( $this->options['view'] );
if ( !$this->getConf( 'customviews' ) )
$this->options['view'] = '';
else if ( !preg_match( '/^SELECT\s/i', trim( $this->options['view'] ) ) )
$this->options['view'] = '';
$this->options['wikimarkup'] = self::asBool( $this->options['wikimarkup'] );
$this->options['simplenav'] = self::asBool( $this->options['simplenav'] );
if ( ctype_digit( trim( $this->options['rowsperpage'] ) ) )
{
$state =& $this->getSession();
if ( !is_integer( $state['num'] ) )
$state['num'] = intval( $this->options['rowsperpage'] );
}
// parse code for contained definitions
$this->parseDefinition( $code );
try
{
// look for available action to perform on selected table
// support preventing CSRF ...
foreach ( $this->getInput() as $key => $dummy )
{
if ( !preg_match( '/^cmd([a-z]+)(\d*)(_x)?$/i', $key, $matches ) )
continue;
$action = strtolower( trim( $matches[1] ) );
$rowid = intval( $matches[2] );
if ( $rowid )
$rowACL = $this->getRowACL( $rowid );
else
$rowid = $rowACL = null;
if ( $action === 'reset' )
{
$state =& $this->getSession();
$state = array();
continue;
}
if ( !$this->isAuthorizedMulti( $rowACL, $this->options, 'may'.$action ) )
{
// user isn't authorized to perform this action
$this->render( '<div class="error">' .
sprintf( $this->getLang( 'accessdenied' ),
$action, $this->table ) . '</div>' );
continue;
}
if ( ( $this->getSingleNumericPrimaryKey() !== false ) ||
in_array( $action, array( 'drop', ) ) )
// perform optionally requested action
switch ( $action )
{
case 'inspect' :// show record details (read-only)
case 'insert' : // show record editor to insert
case 'edit' : // show record editor to adjust
do
{
if ( ( $action == 'insert' ) && $rowid )
{
// insert record starting with duplicate
// of existing one ...
if ( !$this->isAuthorizedMulti( $rowACL, $this->options, 'mayinspect' ) )
{
// user isn't authorized to perform this action
$this->render( '<div class="error">' .
sprintf( $this->getLang( 'accessdenied' ),
$action, $this->table ) . '</div>' );
break;
}
// use duplicate of selected record
$duplicateRowID = $rowid;
// but don't overwrite it!
$rowid = null;
}
else
$duplicateRowID = null;
// invoke editor/single record view
$readonly = ( $action == 'inspect' );
$result = $this->editRecord( $rowid, $readonly,
$duplicateRowID,
$rowACL );
if ( !$result )
// skip rendering table, rendered single
return;
if ( is_integer( $result ) )
{
// switch to selected record
$rowid = $result;
continue;
}
break;
}
while ( true );
break;
case 'delete' :
$this->deleteRecord( $rowid );
break;
case 'drop' :
$this->dropTable();
break;
default :
$method = array( &$this, '__handle_'.$action );
if ( is_callable( $method ) )
if ( !call_user_func( $method, $rowid ) )
return;
}
}
if ( !$this->exists( $this->table ) )
// (re-)create table as it is missing (e.g. after dropping)
$this->createTable();
/*
* finally render table
*/
// check user's authorization to view table
if ( $this->isAuthorized( $this->options['mayview'] ) )
// user may view table
$this->showTable( true, false, false, $this->options['view'] );
}
catch ( PDOException $e )
{
throw new Exception( sprintf( $this->getLang( 'badinteraction' ),
$e->getMessage(), $e->getLine() ) );
}
}
catch ( Exception $e )
{
$this->render( '<div class="error">' .
sprintf( $this->getLang( 'deferror' ),
$e->getMessage(), $e->getLine(), $e->getFile() ) .
'</div>' );
$resetCmd = $this->varname( 'cmdreset' );
$viewCmd = $this->varname( 'view' );
$btnSession = $this->getLang( 'btnResetSession' );
$btnTable = $this->getLang( 'btnViewTable' );
$this->render( $this->wrapInForm( <<<EOT
<input type="submit" name="$resetCmd" value="$btnSession" />
<input type="submit" name="$viewCmd" value="$btnTable" />
EOT
) );
}
}
protected function getACLCol()
{
foreach ( $this->meta as $name => $def )
if ( $def['isColumn'] && ( $def['format'] == 'acl' ) )
return $name;
return null;
}
protected function getRowACL( $rowid )
{
$session =& $this->getSession();
if ( !is_array( $session['rowACLs'] ) )
$session['rowACLs'] = array();
if ( !isset( $session['rowACLs'][$rowid] ) )
{
$aclName = $this->getACLCol();
$idColumn = $this->getSingleNumericPrimaryKey();
if ( $aclName && $idColumn )
{
$sql = sprintf( 'SELECT %s FROM %s WHERE %s=?', $aclName,
$this->table, $idColumn );
$st = $this->db->prepare( $sql );
if ( !$st )
throw new PDOException( $this->getLang( 'aclprepare' ) );
if ( !$st->execute( array( $rowid ) ) )
throw new PDOException( $this->getLang( 'aclexecute' ) );
$row = $st->fetch( PDO::FETCH_NUM );
$st->closeCursor();
$session['rowACLs'][$rowid] = trim( $row[0] );
}
}
return $session['rowACLs'][$rowid] ? $session['rowACLs'][$rowid] : null;
}
protected function dropRowACL( $rowid )
{
$session =& $this->getSession();
if ( $session['rowACLs'][$rowid] )
unset( $session['rowACLs'] );
}
/**
* Creates managed table on demand.
*
*/
protected function createTable()
{
if ( empty( $this->meta ) )
throw new Exception( $this->getLang( 'defmissing' ) );
// extract all column definitions
$cols = array_map( create_function( '$a','return $a[definition];' ),
$this->meta );
// compile CREATE TABLE-statement using linebreaks as some versions
// of SQLite engines cache it for schema representation, thus improving
// human-readability ...
$sql = "CREATE TABLE {$this->table}\n(\n\t" . implode( ",\n\t", $cols ).
"\n)";
if ( $this->db->query( $sql ) === false )
throw new PDOException( sprintf( $this->getLang( 'nocreatetable' ),
$this->table ) );
$this->log( 'create', $this->table );
}
/**
* Renders single record for editing (or inspecting if $readOnly is true).
*
* @param integer $rowid unique numeric ID of record to edit/inspect
* @param boolean $readOnly if true, the record is rendered read-only
* @param integer $duplicateOf unique numeric ID of record to duplicate
* @return boolean if true, the table/list shouldn't be rendered
*/
protected function editRecord( $rowid, $readOnly, $duplicateOf = null,
$rowACL = null )
{
$ioIndex = $this->getIndex();
$input = $this->getInput();
$idColumn = $this->getSingleNumericPrimaryKey();
$isNew = !$rowid || $duplicateOf;
/**
* Obtain lock for exclusively accessing selected record
*/
if ( $rowid && !$readOnly && !$this->obtainLock( $this->table, $rowid ) )
{
$this->render( '<div class="error">' . $this->getLang( 'reclocked' ) . '</div>' );
return true;
}
/*
* prepare session to contain data specific to this editor
*/
$state =& $this->getSession();
$store =& $this->getEditorSession();
$errors = array();
/*
* process input data updating record and handle contained commands
*/
if ( $input && ( $input['____single'] === md5( $rowid ) ) )
{
// select result to return depending on selected navigation mode
if ( $input['____nav'] )
{
if ( $input['____nav'][0] == 'P' )
$state['nav'] = 'previous';
else
$state['nav'] = 'next';
$result = intval( substr( $input['____nav'], 1 ) );