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friendica/src/Database/DBStructure.php
Hypolite Petovan 0e0fff3324 Correctly escape identifier names 
- Add support for schema, multiple tables in $table parameters
- Remove Database->formatTableName method
2019-07-29 00:23:40 -04:00

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<?php
/**
* @file src/Database/DBStructure.php
*/
namespace Friendica\Database;
use Exception;
use Friendica\Core\Config;
use Friendica\Core\Hook;
use Friendica\Core\L10n;
use Friendica\Core\Logger;
use Friendica\Util\DateTimeFormat;
require_once 'include/dba.php';
/**
* @brief This class contain functions for the database management
*
* This class contains functions that doesn't need to know if pdo, mysqli or whatever is used.
*/
class DBStructure
{
const UPDATE_NOT_CHECKED = 0; // Database check wasn't executed before
const UPDATE_SUCCESSFUL = 1; // Database check was successful
const UPDATE_FAILED = 2; // Database check failed
const RENAME_COLUMN = 0;
const RENAME_PRIMARY_KEY = 1;
/**
* Database structure definition loaded from config/dbstructure.config.php
*
* @var array
*/
private static $definition = [];
/*
* Converts all tables from MyISAM to InnoDB
*/
public static function convertToInnoDB()
{
$tables = DBA::selectToArray(
['information_schema' => 'tables'],
['table_name'],
['engine' => 'MyISAM', 'table_schema' => DBA::databaseName()]
);
if (!DBA::isResult($tables)) {
echo L10n::t('There are no tables on MyISAM.') . "\n";
return;
}
foreach ($tables AS $table) {
$sql = "ALTER TABLE " . DBA::quoteIdentifier($table['TABLE_NAME']) . " engine=InnoDB;";
echo $sql . "\n";
$result = DBA::e($sql);
if (!DBA::isResult($result)) {
self::printUpdateError($sql);
}
}
}
/**
* @brief Print out database error messages
*
* @param string $message Message to be added to the error message
*
* @return string Error message
*/
private static function printUpdateError($message)
{
echo L10n::t("\nError %d occurred during database update:\n%s\n",
DBA::errorNo(), DBA::errorMessage());
return L10n::t('Errors encountered performing database changes: ') . $message . EOL;
}
public static function printStructure($basePath)
{
$database = self::definition($basePath, false);
echo "-- ------------------------------------------\n";
echo "-- " . FRIENDICA_PLATFORM . " " . FRIENDICA_VERSION . " (" . FRIENDICA_CODENAME, ")\n";
echo "-- DB_UPDATE_VERSION " . DB_UPDATE_VERSION . "\n";
echo "-- ------------------------------------------\n\n\n";
foreach ($database AS $name => $structure) {
echo "--\n";
echo "-- TABLE $name\n";
echo "--\n";
self::createTable($name, $structure, true, false);
echo "\n";
}
}
/**
* Loads the database structure definition from the config/dbstructure.config.php file.
* On first pass, defines DB_UPDATE_VERSION constant.
*
* @see static/dbstructure.config.php
* @param boolean $with_addons_structure Whether to tack on addons additional tables
* @param string $basePath The base path of this application
* @return array
* @throws Exception
*/
public static function definition($basePath, $with_addons_structure = true)
{
if (!self::$definition) {
$filename = $basePath . '/static/dbstructure.config.php';
if (!is_readable($filename)) {
throw new Exception('Missing database structure config file static/dbstructure.config.php');
}
$definition = require $filename;
if (!$definition) {
throw new Exception('Corrupted database structure config file static/dbstructure.config.php');
}
self::$definition = $definition;
} else {
$definition = self::$definition;
}
if ($with_addons_structure) {
Hook::callAll('dbstructure_definition', $definition);
}
return $definition;
}
private static function createTable($name, $structure, $verbose, $action)
{
$r = true;
$engine = "";
$comment = "";
$sql_rows = [];
$primary_keys = [];
foreach ($structure["fields"] AS $fieldname => $field) {
$sql_rows[] = "`" . DBA::escape($fieldname) . "` " . self::FieldCommand($field);
if (!empty($field['primary'])) {
$primary_keys[] = $fieldname;
}
}
if (!empty($structure["indexes"])) {
foreach ($structure["indexes"] AS $indexname => $fieldnames) {
$sql_index = self::createIndex($indexname, $fieldnames, "");
if (!is_null($sql_index)) {
$sql_rows[] = $sql_index;
}
}
}
if (isset($structure["engine"])) {
$engine = " ENGINE=" . $structure["engine"];
}
if (isset($structure["comment"])) {
$comment = " COMMENT='" . DBA::escape($structure["comment"]) . "'";
}
$sql = implode(",\n\t", $sql_rows);
$sql = sprintf("CREATE TABLE IF NOT EXISTS `%s` (\n\t", DBA::escape($name)) . $sql .
"\n)" . $engine . " DEFAULT COLLATE utf8mb4_general_ci" . $comment;
if ($verbose) {
echo $sql . ";\n";
}
if ($action) {
$r = DBA::e($sql);
}
return $r;
}
private static function FieldCommand($parameters, $create = true)
{
$fieldstruct = $parameters["type"];
if (isset($parameters["Collation"])) {
$fieldstruct .= " COLLATE " . $parameters["Collation"];
}
if (isset($parameters["not null"])) {
$fieldstruct .= " NOT NULL";
}
if (isset($parameters["default"])) {
if (strpos(strtolower($parameters["type"]), "int") !== false) {
$fieldstruct .= " DEFAULT " . $parameters["default"];
} else {
$fieldstruct .= " DEFAULT '" . $parameters["default"] . "'";
}
}
if (isset($parameters["extra"])) {
$fieldstruct .= " " . $parameters["extra"];
}
if (isset($parameters["comment"])) {
$fieldstruct .= " COMMENT '" . DBA::escape($parameters["comment"]) . "'";
}
/*if (($parameters["primary"] != "") && $create)
$fieldstruct .= " PRIMARY KEY";*/
return ($fieldstruct);
}
private static function createIndex($indexname, $fieldnames, $method = "ADD")
{
$method = strtoupper(trim($method));
if ($method != "" && $method != "ADD") {
throw new Exception("Invalid parameter 'method' in self::createIndex(): '$method'");
}
if (in_array($fieldnames[0], ["UNIQUE", "FULLTEXT"])) {
$index_type = array_shift($fieldnames);
$method .= " " . $index_type;
}
$names = "";
foreach ($fieldnames AS $fieldname) {
if ($names != "") {
$names .= ",";
}
if (preg_match('|(.+)\((\d+)\)|', $fieldname, $matches)) {
$names .= "`" . DBA::escape($matches[1]) . "`(" . intval($matches[2]) . ")";
} else {
$names .= "`" . DBA::escape($fieldname) . "`";
}
}
if ($indexname == "PRIMARY") {
return sprintf("%s PRIMARY KEY(%s)", $method, $names);
}
$sql = sprintf("%s INDEX `%s` (%s)", $method, DBA::escape($indexname), $names);
return ($sql);
}
/**
* Updates DB structure and returns eventual errors messages
*
* @param string $basePath The base path of this application
* @param bool $verbose
* @param bool $action Whether to actually apply the update
* @param bool $install Is this the initial update during the installation?
* @param array $tables An array of the database tables
* @param array $definition An array of the definition tables
* @return string Empty string if the update is successful, error messages otherwise
* @throws Exception
*/
public static function update($basePath, $verbose, $action, $install = false, array $tables = null, array $definition = null)
{
if ($action && !$install) {
Config::set('system', 'maintenance', 1);
Config::set('system', 'maintenance_reason', L10n::t('%s: Database update', DateTimeFormat::utcNow() . ' ' . date('e')));
}
$errors = '';
Logger::log('updating structure', Logger::DEBUG);
// Get the current structure
$database = [];
if (is_null($tables)) {
$tables = q("SHOW TABLES");
}
if (DBA::isResult($tables)) {
foreach ($tables AS $table) {
$table = current($table);
Logger::log(sprintf('updating structure for table %s ...', $table), Logger::DEBUG);
$database[$table] = self::tableStructure($table);
}
}
// Get the definition
if (is_null($definition)) {
$definition = self::definition($basePath);
}
// MySQL >= 5.7.4 doesn't support the IGNORE keyword in ALTER TABLE statements
if ((version_compare(DBA::serverInfo(), '5.7.4') >= 0) &&
!(strpos(DBA::serverInfo(), 'MariaDB') !== false)) {
$ignore = '';
} else {
$ignore = ' IGNORE';
}
// Compare it
foreach ($definition AS $name => $structure) {
$is_new_table = false;
$group_by = "";
$sql3 = "";
$is_unique = false;
$temp_name = $name;
if (!isset($database[$name])) {
$r = self::createTable($name, $structure, $verbose, $action);
if (!DBA::isResult($r)) {
$errors .= self::printUpdateError($name);
}
$is_new_table = true;
} else {
foreach ($structure["indexes"] AS $indexname => $fieldnames) {
if (isset($database[$name]["indexes"][$indexname])) {
$current_index_definition = implode(",", $database[$name]["indexes"][$indexname]);
} else {
$current_index_definition = "__NOT_SET__";
}
$new_index_definition = implode(",", $fieldnames);
if ($current_index_definition != $new_index_definition) {
if ($fieldnames[0] == "UNIQUE") {
$is_unique = true;
if ($ignore == "") {
$temp_name = "temp-" . $name;
}
}
}
}
/*
* Drop the index if it isn't present in the definition
* or the definition differ from current status
* and index name doesn't start with "local_"
*/
foreach ($database[$name]["indexes"] as $indexname => $fieldnames) {
$current_index_definition = implode(",", $fieldnames);
if (isset($structure["indexes"][$indexname])) {
$new_index_definition = implode(",", $structure["indexes"][$indexname]);
} else {
$new_index_definition = "__NOT_SET__";
}
if ($current_index_definition != $new_index_definition && substr($indexname, 0, 6) != 'local_') {
$sql2 = self::dropIndex($indexname);
if ($sql3 == "") {
$sql3 = "ALTER" . $ignore . " TABLE `" . $temp_name . "` " . $sql2;
} else {
$sql3 .= ", " . $sql2;
}
}
}
// Compare the field structure field by field
foreach ($structure["fields"] AS $fieldname => $parameters) {
if (!isset($database[$name]["fields"][$fieldname])) {
$sql2 = self::addTableField($fieldname, $parameters);
if ($sql3 == "") {
$sql3 = "ALTER" . $ignore . " TABLE `" . $temp_name . "` " . $sql2;
} else {
$sql3 .= ", " . $sql2;
}
} else {
// Compare the field definition
$field_definition = $database[$name]["fields"][$fieldname];
// Remove the relation data that is used for the referential integrity
unset($parameters['relation']);
// We change the collation after the indexes had been changed.
// This is done to avoid index length problems.
// So here we always ensure that there is no need to change it.
unset($parameters['Collation']);
unset($field_definition['Collation']);
// Only update the comment when it is defined
if (!isset($parameters['comment'])) {
$parameters['comment'] = "";
}
$current_field_definition = DBA::cleanQuery(implode(",", $field_definition));
$new_field_definition = DBA::cleanQuery(implode(",", $parameters));
if ($current_field_definition != $new_field_definition) {
$sql2 = self::modifyTableField($fieldname, $parameters);
if ($sql3 == "") {
$sql3 = "ALTER" . $ignore . " TABLE `" . $temp_name . "` " . $sql2;
} else {
$sql3 .= ", " . $sql2;
}
}
}
}
}
/*
* Create the index if the index don't exists in database
* or the definition differ from the current status.
* Don't create keys if table is new
*/
if (!$is_new_table) {
foreach ($structure["indexes"] AS $indexname => $fieldnames) {
if (isset($database[$name]["indexes"][$indexname])) {
$current_index_definition = implode(",", $database[$name]["indexes"][$indexname]);
} else {
$current_index_definition = "__NOT_SET__";
}
$new_index_definition = implode(",", $fieldnames);
if ($current_index_definition != $new_index_definition) {
$sql2 = self::createIndex($indexname, $fieldnames);
// Fetch the "group by" fields for unique indexes
$group_by = self::groupBy($fieldnames);
if ($sql2 != "") {
if ($sql3 == "") {
$sql3 = "ALTER" . $ignore . " TABLE `" . $temp_name . "` " . $sql2;
} else {
$sql3 .= ", " . $sql2;
}
}
}
}
if (isset($database[$name]["table_status"]["Comment"])) {
$structurecomment = defaults($structure, "comment", "");
if ($database[$name]["table_status"]["Comment"] != $structurecomment) {
$sql2 = "COMMENT = '" . DBA::escape($structurecomment) . "'";
if ($sql3 == "") {
$sql3 = "ALTER" . $ignore . " TABLE `" . $temp_name . "` " . $sql2;
} else {
$sql3 .= ", " . $sql2;
}
}
}
if (isset($database[$name]["table_status"]["Engine"]) && isset($structure['engine'])) {
if ($database[$name]["table_status"]["Engine"] != $structure['engine']) {
$sql2 = "ENGINE = '" . DBA::escape($structure['engine']) . "'";
if ($sql3 == "") {
$sql3 = "ALTER" . $ignore . " TABLE `" . $temp_name . "` " . $sql2;
} else {
$sql3 .= ", " . $sql2;
}
}
}
if (isset($database[$name]["table_status"]["Collation"])) {
if ($database[$name]["table_status"]["Collation"] != 'utf8mb4_general_ci') {
$sql2 = "DEFAULT COLLATE utf8mb4_general_ci";
if ($sql3 == "") {
$sql3 = "ALTER" . $ignore . " TABLE `" . $temp_name . "` " . $sql2;
} else {
$sql3 .= ", " . $sql2;
}
}
}
if ($sql3 != "") {
$sql3 .= "; ";
}
// Now have a look at the field collations
// Compare the field structure field by field
foreach ($structure["fields"] AS $fieldname => $parameters) {
// Compare the field definition
$field_definition = defaults($database[$name]["fields"], $fieldname, ['Collation' => '']);
// Define the default collation if not given
if (!isset($parameters['Collation']) && !empty($field_definition['Collation'])) {
$parameters['Collation'] = 'utf8mb4_general_ci';
} else {
$parameters['Collation'] = null;
}
if ($field_definition['Collation'] != $parameters['Collation']) {
$sql2 = self::modifyTableField($fieldname, $parameters);
if (($sql3 == "") || (substr($sql3, -2, 2) == "; ")) {
$sql3 .= "ALTER" . $ignore . " TABLE `" . $temp_name . "` " . $sql2;
} else {
$sql3 .= ", " . $sql2;
}
}
}
}
if ($sql3 != "") {
if (substr($sql3, -2, 2) != "; ") {
$sql3 .= ";";
}
$field_list = '';
if ($is_unique && $ignore == '') {
foreach ($database[$name]["fields"] AS $fieldname => $parameters) {
$field_list .= 'ANY_VALUE(`' . $fieldname . '`),';
}
$field_list = rtrim($field_list, ',');
}
if ($verbose) {
// Ensure index conversion to unique removes duplicates
if ($is_unique && ($temp_name != $name)) {
if ($ignore != "") {
echo "SET session old_alter_table=1;\n";
} else {
echo "DROP TABLE IF EXISTS `" . $temp_name . "`;\n";
echo "CREATE TABLE `" . $temp_name . "` LIKE `" . $name . "`;\n";
}
}
echo $sql3 . "\n";
if ($is_unique && ($temp_name != $name)) {
if ($ignore != "") {
echo "SET session old_alter_table=0;\n";
} else {
echo "INSERT INTO `" . $temp_name . "` SELECT " . DBA::anyValueFallback($field_list) . " FROM `" . $name . "`" . $group_by . ";\n";
echo "DROP TABLE `" . $name . "`;\n";
echo "RENAME TABLE `" . $temp_name . "` TO `" . $name . "`;\n";
}
}
}
if ($action) {
if (!$install) {
Config::set('system', 'maintenance_reason', L10n::t('%s: updating %s table.', DateTimeFormat::utcNow() . ' ' . date('e'), $name));
}
// Ensure index conversion to unique removes duplicates
if ($is_unique && ($temp_name != $name)) {
if ($ignore != "") {
DBA::e("SET session old_alter_table=1;");
} else {
$r = DBA::e("DROP TABLE IF EXISTS `" . $temp_name . "`;");
if (!DBA::isResult($r)) {
$errors .= self::printUpdateError($sql3);
return $errors;
}
$r = DBA::e("CREATE TABLE `" . $temp_name . "` LIKE `" . $name . "`;");
if (!DBA::isResult($r)) {
$errors .= self::printUpdateError($sql3);
return $errors;
}
}
}
$r = DBA::e($sql3);
if (!DBA::isResult($r)) {
$errors .= self::printUpdateError($sql3);
}
if ($is_unique && ($temp_name != $name)) {
if ($ignore != "") {
DBA::e("SET session old_alter_table=0;");
} else {
$r = DBA::e("INSERT INTO `" . $temp_name . "` SELECT " . $field_list . " FROM `" . $name . "`" . $group_by . ";");
if (!DBA::isResult($r)) {
$errors .= self::printUpdateError($sql3);
return $errors;
}
$r = DBA::e("DROP TABLE `" . $name . "`;");
if (!DBA::isResult($r)) {
$errors .= self::printUpdateError($sql3);
return $errors;
}
$r = DBA::e("RENAME TABLE `" . $temp_name . "` TO `" . $name . "`;");
if (!DBA::isResult($r)) {
$errors .= self::printUpdateError($sql3);
return $errors;
}
}
}
}
}
}
if ($action && !$install) {
Config::set('system', 'maintenance', 0);
Config::set('system', 'maintenance_reason', '');
if ($errors) {
Config::set('system', 'dbupdate', self::UPDATE_FAILED);
} else {
Config::set('system', 'dbupdate', self::UPDATE_SUCCESSFUL);
}
}
return $errors;
}
private static function tableStructure($table)
{
$structures = q("DESCRIBE `%s`", $table);
$full_columns = q("SHOW FULL COLUMNS FROM `%s`", $table);
$indexes = q("SHOW INDEX FROM `%s`", $table);
$table_status = q("SHOW TABLE STATUS WHERE `name` = '%s'", $table);
if (DBA::isResult($table_status)) {
$table_status = $table_status[0];
} else {
$table_status = [];
}
$fielddata = [];
$indexdata = [];
if (DBA::isResult($indexes)) {
foreach ($indexes AS $index) {
if ($index["Key_name"] != "PRIMARY" && $index["Non_unique"] == "0" && !isset($indexdata[$index["Key_name"]])) {
$indexdata[$index["Key_name"]] = ["UNIQUE"];
}
if ($index["Index_type"] == "FULLTEXT" && !isset($indexdata[$index["Key_name"]])) {
$indexdata[$index["Key_name"]] = ["FULLTEXT"];
}
$column = $index["Column_name"];
if ($index["Sub_part"] != "") {
$column .= "(" . $index["Sub_part"] . ")";
}
$indexdata[$index["Key_name"]][] = $column;
}
}
if (DBA::isResult($structures)) {
foreach ($structures AS $field) {
// Replace the default size values so that we don't have to define them
$search = ['tinyint(1)', 'tinyint(3) unsigned', 'tinyint(4)', 'smallint(5) unsigned', 'smallint(6)', 'mediumint(8) unsigned', 'mediumint(9)', 'bigint(20)', 'int(10) unsigned', 'int(11)'];
$replace = ['boolean', 'tinyint unsigned', 'tinyint', 'smallint unsigned', 'smallint', 'mediumint unsigned', 'mediumint', 'bigint', 'int unsigned', 'int'];
$field["Type"] = str_replace($search, $replace, $field["Type"]);
$fielddata[$field["Field"]]["type"] = $field["Type"];
if ($field["Null"] == "NO") {
$fielddata[$field["Field"]]["not null"] = true;
}
if (isset($field["Default"])) {
$fielddata[$field["Field"]]["default"] = $field["Default"];
}
if ($field["Extra"] != "") {
$fielddata[$field["Field"]]["extra"] = $field["Extra"];
}
if ($field["Key"] == "PRI") {
$fielddata[$field["Field"]]["primary"] = true;
}
}
}
if (DBA::isResult($full_columns)) {
foreach ($full_columns AS $column) {
$fielddata[$column["Field"]]["Collation"] = $column["Collation"];
$fielddata[$column["Field"]]["comment"] = $column["Comment"];
}
}
return ["fields" => $fielddata, "indexes" => $indexdata, "table_status" => $table_status];
}
private static function dropIndex($indexname)
{
$sql = sprintf("DROP INDEX `%s`", DBA::escape($indexname));
return ($sql);
}
private static function addTableField($fieldname, $parameters)
{
$sql = sprintf("ADD `%s` %s", DBA::escape($fieldname), self::FieldCommand($parameters));
return ($sql);
}
private static function modifyTableField($fieldname, $parameters)
{
$sql = sprintf("MODIFY `%s` %s", DBA::escape($fieldname), self::FieldCommand($parameters, false));
return ($sql);
}
/**
* Constructs a GROUP BY clause from a UNIQUE index definition.
*
* @param array $fieldnames
* @return string
*/
private static function groupBy(array $fieldnames)
{
if ($fieldnames[0] != "UNIQUE") {
return "";
}
array_shift($fieldnames);
$names = "";
foreach ($fieldnames AS $fieldname) {
if ($names != "") {
$names .= ",";
}
if (preg_match('|(.+)\((\d+)\)|', $fieldname, $matches)) {
$names .= "`" . DBA::escape($matches[1]) . "`";
} else {
$names .= "`" . DBA::escape($fieldname) . "`";
}
}
$sql = sprintf(" GROUP BY %s", $names);
return $sql;
}
/**
* Renames columns or the primary key of a table
*
* @todo You cannot rename a primary key if "auto increment" is set
*
* @param string $table Table name
* @param array $columns Columns Syntax for Rename: [ $old1 => [ $new1, $type1 ], $old2 => [ $new2, $type2 ], ... ] )
* Syntax for Primary Key: [ $col1, $col2, ...] )
* @param int $type The type of renaming (Default is Column)
*
* @return boolean Was the renaming successful?
* @throws Exception
*/
public static function rename($table, $columns, $type = self::RENAME_COLUMN)
{
if (empty($table) || empty($columns)) {
return false;
}
if (!is_array($columns)) {
return false;
}
$table = DBA::escape($table);
$sql = "ALTER TABLE `" . $table . "`";
switch ($type) {
case self::RENAME_COLUMN:
if (!self::existsColumn($table, array_keys($columns))) {
return false;
}
$sql .= implode(',', array_map(
function ($to, $from) {
return " CHANGE `" . $from . "` `" . $to[0] . "` " . $to[1];
},
$columns,
array_keys($columns)
));
break;
case self::RENAME_PRIMARY_KEY:
if (!self::existsColumn($table, $columns)) {
return false;
}
$sql .= " DROP PRIMARY KEY, ADD PRIMARY KEY(`" . implode('`, `', $columns) . "`)";
break;
default:
return false;
}
$sql .= ";";
$stmt = DBA::p($sql);
if (is_bool($stmt)) {
$retval = $stmt;
} else {
$retval = true;
}
DBA::close($stmt);
return $retval;
}
/**
* Check if the columns of the table exists
*
* @param string $table Table name
* @param array $columns Columns to check ( Syntax: [ $col1, $col2, .. ] )
*
* @return boolean Does the table exist?
* @throws Exception
*/
public static function existsColumn($table, $columns = [])
{
if (empty($table)) {
return false;
}
if (is_null($columns) || empty($columns)) {
return self::existsTable($table);
}
$table = DBA::escape($table);
foreach ($columns AS $column) {
$sql = "SHOW COLUMNS FROM `" . $table . "` LIKE '" . $column . "';";
$stmt = DBA::p($sql);
if (is_bool($stmt)) {
$retval = $stmt;
} else {
$retval = (DBA::numRows($stmt) > 0);
}
DBA::close($stmt);
if (!$retval) {
return false;
}
}
return true;
}
/**
* Check if a table exists
*
* @param string|array $table Table name
*
* @return boolean Does the table exist?
* @throws Exception
*/
public static function existsTable($table)
{
if (empty($table)) {
return false;
}
if (is_array($table)) {
$condition = ['table_schema' => key($table), 'table_name' => current($table)];
} else {
$condition = ['table_schema' => DBA::databaseName(), 'table_name' => $table];
}
$result = DBA::exists(['information_schema' => 'tables'], $condition);
return $result;
}
/**
* Returns the columns of a table
*
* @param string $table Table name
*
* @return array An array of the table columns
* @throws Exception
*/
public static function getColumns($table)
{
$stmtColumns = DBA::p("SHOW COLUMNS FROM `" . $table . "`");
return DBA::toArray($stmtColumns);
}
}
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