| 1 |
<?php |
| 2 |
/** |
| 3 |
* MCP Tools for Read-Only Database Inspection |
| 4 |
* |
| 5 |
* Provides safe, read-only database access for AI-assisted analysis. |
| 6 |
* Only SELECT, SHOW, DESCRIBE, and EXPLAIN statements are permitted. |
| 7 |
* All tools require manage_options capability (admin). |
| 8 |
* |
| 9 |
* @package MetaSync |
| 10 |
* @subpackage MCP_Server/Tools |
| 11 |
*/ |
| 12 |
|
| 13 |
if (!defined('ABSPATH')) { |
| 14 |
exit; |
| 15 |
} |
| 16 |
|
| 17 |
require_once plugin_dir_path(dirname(__FILE__)) . 'class-mcp-tool-base.php'; |
| 18 |
|
| 19 |
/** |
| 20 |
* DB Tables Tool |
| 21 |
* |
| 22 |
* Lists all database tables with row counts and size estimates. |
| 23 |
*/ |
| 24 |
class MCP_Tool_DB_Tables extends MCP_Tool_Base { |
| 25 |
|
| 26 |
public function get_name() { |
| 27 |
return 'wordpress_db_tables'; |
| 28 |
} |
| 29 |
|
| 30 |
public function get_description() { |
| 31 |
return 'List all database tables with row counts and size (MB). Use this to understand the database structure before running targeted queries.'; |
| 32 |
} |
| 33 |
|
| 34 |
public function get_input_schema() { |
| 35 |
return [ |
| 36 |
'type' => 'object', |
| 37 |
'properties' => [ |
| 38 |
'prefix_only' => [ |
| 39 |
'type' => 'boolean', |
| 40 |
'description' => 'If true (default), only show tables matching the WordPress table prefix', |
| 41 |
], |
| 42 |
], |
| 43 |
]; |
| 44 |
} |
| 45 |
|
| 46 |
public function execute($params) { |
| 47 |
$this->require_capability('manage_options'); |
| 48 |
|
| 49 |
global $wpdb; |
| 50 |
|
| 51 |
$prefix_only = !isset($params['prefix_only']) || $params['prefix_only'] !== false; |
| 52 |
|
| 53 |
$rows = $wpdb->get_results( |
| 54 |
$wpdb->prepare( |
| 55 |
'SELECT |
| 56 |
table_name AS `table`, |
| 57 |
table_rows AS `rows_approx`, |
| 58 |
ROUND((data_length + index_length) / 1024 / 1024, 4) AS `size_mb`, |
| 59 |
data_length AS `data_bytes`, |
| 60 |
index_length AS `index_bytes`, |
| 61 |
create_time AS `created`, |
| 62 |
update_time AS `last_updated` |
| 63 |
FROM information_schema.tables |
| 64 |
WHERE table_schema = %s |
| 65 |
ORDER BY (data_length + index_length) DESC', |
| 66 |
DB_NAME |
| 67 |
), |
| 68 |
ARRAY_A |
| 69 |
); |
| 70 |
|
| 71 |
if ($prefix_only) { |
| 72 |
$prefix = $wpdb->prefix; |
| 73 |
$rows = array_values(array_filter($rows, function($r) use ($prefix) { |
| 74 |
return strpos($r['table'], $prefix) === 0; |
| 75 |
})); |
| 76 |
} |
| 77 |
|
| 78 |
// Cast numeric columns |
| 79 |
foreach ($rows as &$r) { |
| 80 |
$r['rows_approx'] = (int) $r['rows_approx']; |
| 81 |
$r['size_mb'] = (float) $r['size_mb']; |
| 82 |
} |
| 83 |
unset($r); |
| 84 |
|
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return $this->success([ |
| 86 |
'total' => count($rows), |
| 87 |
'tables' => $rows, |
| 88 |
]); |
| 89 |
} |
| 90 |
} |
| 91 |
|
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/** |
| 93 |
* DB Describe Tool |
| 94 |
* |
| 95 |
* Returns the column definitions for a specific table. |
| 96 |
*/ |
| 97 |
class MCP_Tool_DB_Describe extends MCP_Tool_Base { |
| 98 |
|
| 99 |
public function get_name() { |
| 100 |
return 'wordpress_db_describe'; |
| 101 |
} |
| 102 |
|
| 103 |
public function get_description() { |
| 104 |
return 'Describe a database table: column names, types, nullability, keys, and defaults. Use before writing a SELECT query to know the exact column names.'; |
| 105 |
} |
| 106 |
|
| 107 |
public function get_input_schema() { |
| 108 |
return [ |
| 109 |
'type' => 'object', |
| 110 |
'properties' => [ |
| 111 |
'table' => [ |
| 112 |
'type' => 'string', |
| 113 |
'description' => 'Table name (with or without prefix, e.g. "posts" or "wp_posts")', |
| 114 |
], |
| 115 |
], |
| 116 |
'required' => ['table'], |
| 117 |
]; |
| 118 |
} |
| 119 |
|
| 120 |
public function execute($params) { |
| 121 |
$this->validate_params($params); |
| 122 |
$this->require_capability('manage_options'); |
| 123 |
|
| 124 |
global $wpdb; |
| 125 |
|
| 126 |
$table = $this->resolve_table_name(sanitize_text_field($params['table'])); |
| 127 |
$this->assert_table_exists($table); |
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|
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// phpcs:ignore WordPress.DB.PreparedSQL.InterpolatedNotPrepared -- table name validated above |
| 130 |
$columns = $wpdb->get_results("DESCRIBE `{$table}`", ARRAY_A); |
| 131 |
|
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$indexes = $wpdb->get_results("SHOW INDEX FROM `{$table}`", ARRAY_A); |
| 133 |
$index_map = []; |
| 134 |
foreach ($indexes as $idx) { |
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$col = $idx['Column_name']; |
| 136 |
$index_map[$col][] = [ |
| 137 |
'key_name' => $idx['Key_name'], |
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'non_unique' => (bool) $idx['Non_unique'], |
| 139 |
'index_type' => $idx['Index_type'], |
| 140 |
]; |
| 141 |
} |
| 142 |
|
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$result = []; |
| 144 |
foreach ($columns as $col) { |
| 145 |
$result[] = [ |
| 146 |
'column' => $col['Field'], |
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'type' => $col['Type'], |
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'null' => $col['Null'] === 'YES', |
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'key' => $col['Key'], |
| 150 |
'default' => $col['Default'], |
| 151 |
'extra' => $col['Extra'], |
| 152 |
'indexes' => $index_map[$col['Field']] ?? [], |
| 153 |
]; |
| 154 |
} |
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|
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return $this->success([ |
| 157 |
'table' => $table, |
| 158 |
'columns' => $result, |
| 159 |
]); |
| 160 |
} |
| 161 |
|
| 162 |
private function resolve_table_name($table) { |
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global $wpdb; |
| 164 |
// If already prefixed, use as-is; otherwise prepend prefix |
| 165 |
if (strpos($table, $wpdb->prefix) === 0) { |
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return $table; |
| 167 |
} |
| 168 |
return $wpdb->prefix . $table; |
| 169 |
} |
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|
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private function assert_table_exists($table) { |
| 172 |
global $wpdb; |
| 173 |
// phpcs:ignore WordPress.DB.PreparedSQL.InterpolatedNotPrepared |
| 174 |
$exists = $wpdb->get_var($wpdb->prepare( |
| 175 |
'SELECT COUNT(*) FROM information_schema.tables WHERE table_schema = %s AND table_name = %s', |
| 176 |
DB_NAME, |
| 177 |
$table |
| 178 |
)); |
| 179 |
if (!$exists) { |
| 180 |
throw new Exception("Table '{$table}' does not exist"); |
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} |
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} |
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} |
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|
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/** |
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* DB Select Tool |
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* |
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* Executes a read-only SQL query (SELECT / SHOW / DESCRIBE / EXPLAIN only). |
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* Blocks all write operations. Results capped at 500 rows. |
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*/ |
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class MCP_Tool_DB_Select extends MCP_Tool_Base { |
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|
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public function get_name() { |
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return 'wordpress_db_select'; |
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} |
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|
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public function get_description() { |
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return 'Run a read-only SQL query against the WordPress database. Only SELECT, SHOW, DESCRIBE, and EXPLAIN are allowed — all write operations are blocked. Results are capped at 500 rows. Use wordpress_db_tables and wordpress_db_describe first to understand the schema.'; |
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} |
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|
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public function get_input_schema() { |
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return [ |
| 203 |
'type' => 'object', |
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'properties' => [ |
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'sql' => [ |
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'type' => 'string', |
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'description' => 'SQL query to execute. Must start with SELECT, SHOW, DESCRIBE, or EXPLAIN.', |
| 208 |
], |
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'limit' => [ |
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'type' => 'integer', |
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'description' => 'Max rows to return (1–500, default 100)', |
| 212 |
'minimum' => 1, |
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'maximum' => 500, |
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], |
| 215 |
], |
| 216 |
'required' => ['sql'], |
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]; |
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} |
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|
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// Keywords that must never appear at statement start |
| 221 |
private $blocked_first_keywords = [ |
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'INSERT', 'UPDATE', 'DELETE', 'REPLACE', 'DROP', 'CREATE', |
| 223 |
'ALTER', 'TRUNCATE', 'RENAME', 'GRANT', 'REVOKE', 'CALL', |
| 224 |
'EXEC', 'EXECUTE', 'LOAD', 'IMPORT', |
| 225 |
]; |
| 226 |
|
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// Keywords that should never appear anywhere in the query |
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private $blocked_anywhere = [ |
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'INTO OUTFILE', 'INTO DUMPFILE', 'LOAD_FILE', |
| 230 |
'SLEEP(', 'BENCHMARK(', |
| 231 |
]; |
| 232 |
|
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/** |
| 234 |
* Execute a read-only SQL query. |
| 235 |
* |
| 236 |
* Query timeout behaviour |
| 237 |
* ----------------------- |
| 238 |
* Every query is guarded by a timeout (default 10 seconds) so that a slow |
| 239 |
* or runaway SELECT cannot hang the PHP process. The effective limit is |
| 240 |
* resolved in this order: |
| 241 |
* |
| 242 |
* 1. `METASYNC_MCP_DB_QUERY_TIMEOUT` constant, if defined. |
| 243 |
* 2. The `mcp_db_query_timeout` WordPress filter. |
| 244 |
* 3. The default of 10 seconds. |
| 245 |
* |
| 246 |
* The resolved value is clamped to at least 1 second. |
| 247 |
* |
| 248 |
* The timeout is enforced server-side where possible: |
| 249 |
* |
| 250 |
* - MySQL >= 5.7.8: the statement is prefixed with the |
| 251 |
* `MAX_EXECUTION_TIME(<ms>)` optimizer hint (milliseconds). The hint |
| 252 |
* is only valid for SELECT and is skipped for SHOW / DESCRIBE / |
| 253 |
* EXPLAIN. |
| 254 |
* - MariaDB >= 10.1.1: the statement is wrapped with |
| 255 |
* `SET STATEMENT max_statement_time=<seconds> FOR ...` (seconds, not |
| 256 |
* milliseconds — this is a MariaDB specific distinction). |
| 257 |
* - Older MySQL / MariaDB: no DB-level hint is injected. |
| 258 |
* |
| 259 |
* On all versions, the call is additionally wrapped by a PHP-level |
| 260 |
* `set_time_limit()` fallback scoped to the query, restored in a |
| 261 |
* `finally` block, so the query cannot hang the PHP process beyond the |
| 262 |
* configured timeout + a small safety margin even when no DB-level hint |
| 263 |
* is available. |
| 264 |
* |
| 265 |
* When the DB reports a timeout (MySQL error 3024, MariaDB error 1969, |
| 266 |
* or a `Query execution was interrupted` / `max_statement_time exceeded` |
| 267 |
* message) the tool throws a descriptive `Exception` which the JSON-RPC |
| 268 |
* handler converts into a structured error response. |
| 269 |
* |
| 270 |
* @param array $params { |
| 271 |
* @type string $sql SQL to run (SELECT / SHOW / DESCRIBE / EXPLAIN). |
| 272 |
* @type int $limit Max rows to return (1–500, default 100). |
| 273 |
* } |
| 274 |
* @return array Success payload as returned by {@see self::success()}. |
| 275 |
* @throws Exception If the query is blocked, times out, or the DB errors. |
| 276 |
*/ |
| 277 |
public function execute($params) { |
| 278 |
$this->validate_params($params); |
| 279 |
$this->require_capability('manage_options'); |
| 280 |
|
| 281 |
global $wpdb; |
| 282 |
|
| 283 |
$sql = trim($params['sql']); |
| 284 |
$limit = isset($params['limit']) ? intval($params['limit']) : 100; |
| 285 |
$limit = max(1, min(500, $limit)); |
| 286 |
|
| 287 |
// ── Security checks ────────────────────────────────────────── |
| 288 |
// NOTE: all security checks operate on the ORIGINAL $sql (before any |
| 289 |
// timeout rewriting). Only the timeout-wrapped SQL is passed to |
| 290 |
// $wpdb->get_results() further down. |
| 291 |
|
| 292 |
// 1. Strip leading SQL block/line comments to find the real first keyword |
| 293 |
$stripped = preg_replace('/\A(\s*(\/\*.*?\*\/\s*|--[^\n]*\n?\s*))+/s', '', $sql); |
| 294 |
$first_keyword = strtoupper(preg_replace('/[\s(;].*/s', '', $stripped)); |
| 295 |
|
| 296 |
$allowed_starts = ['SELECT', 'SHOW', 'DESCRIBE', 'DESC', 'EXPLAIN']; |
| 297 |
if (!in_array($first_keyword, $allowed_starts, true)) { |
| 298 |
throw new Exception( |
| 299 |
"Query blocked: only SELECT, SHOW, DESCRIBE, and EXPLAIN are allowed. " . |
| 300 |
"Got: '{$first_keyword}'" |
| 301 |
); |
| 302 |
} |
| 303 |
|
| 304 |
// 2. Block write-operation keywords at statement start (covers stacked queries) |
| 305 |
foreach ($this->blocked_first_keywords as $kw) { |
| 306 |
if (preg_match('/;\s*' . preg_quote($kw, '/') . '\s/i', $sql)) { |
| 307 |
throw new Exception("Query blocked: stacked write statement detected ({$kw})"); |
| 308 |
} |
| 309 |
} |
| 310 |
|
| 311 |
// 3. Block dangerous function / file-access patterns |
| 312 |
$sql_upper = strtoupper($sql); |
| 313 |
foreach ($this->blocked_anywhere as $pattern) { |
| 314 |
if (strpos($sql_upper, $pattern) !== false) { |
| 315 |
throw new Exception("Query blocked: forbidden pattern detected ({$pattern})"); |
| 316 |
} |
| 317 |
} |
| 318 |
|
| 319 |
// ── Execute ────────────────────────────────────────────────── |
| 320 |
$to = $this->apply_query_timeout($sql); |
| 321 |
|
| 322 |
$prev_time_limit = (int) ini_get('max_execution_time'); |
| 323 |
// Give the DB-level hint a chance to fire first; the PHP fallback |
| 324 |
// trails by a small margin so it only kicks in as a hard backstop. |
| 325 |
@set_time_limit($to['timeout'] + 2); |
| 326 |
|
| 327 |
try { |
| 328 |
// phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared -- user-provided query, validated above |
| 329 |
$results = $wpdb->get_results($to['sql'], ARRAY_A); |
| 330 |
} finally { |
| 331 |
@set_time_limit($prev_time_limit); |
| 332 |
} |
| 333 |
|
| 334 |
if ($wpdb->last_error) { |
| 335 |
$err = $wpdb->last_error; |
| 336 |
if ( |
| 337 |
preg_match('/\b3024\b/', $err) || // MySQL ER_QUERY_TIMEOUT |
| 338 |
preg_match('/\b1969\b/', $err) || // MariaDB ER_STATEMENT_TIMEOUT |
| 339 |
stripos($err, 'Query execution was interrupted') !== false || |
| 340 |
stripos($err, 'max_statement_time exceeded') !== false |
| 341 |
) { |
| 342 |
throw new Exception( |
| 343 |
"Query timeout: query exceeded the {$to['timeout']}s limit and was cancelled." |
| 344 |
); |
| 345 |
} |
| 346 |
throw new Exception('Database error: ' . $err); |
| 347 |
} |
| 348 |
|
| 349 |
$total = is_array($results) ? count($results) : 0; |
| 350 |
$trimmed = is_array($results) ? array_slice($results, 0, $limit) : []; |
| 351 |
|
| 352 |
return $this->success([ |
| 353 |
'rows_returned' => count($trimmed), |
| 354 |
'rows_total' => $total, |
| 355 |
'limit_applied' => $total > $limit, |
| 356 |
'results' => $trimmed, |
| 357 |
]); |
| 358 |
} |
| 359 |
|
| 360 |
/** |
| 361 |
* Resolve the effective query timeout and rewrite the SQL to enforce it. |
| 362 |
* |
| 363 |
* @param string $sql Original SQL statement. |
| 364 |
* @return array{sql:string,timeout:int,mechanism:string} |
| 365 |
* The SQL to pass to $wpdb->get_results(), the effective |
| 366 |
* timeout in seconds, and which mechanism applied |
| 367 |
* ('mysql', 'mariadb', or 'php_only'). |
| 368 |
*/ |
| 369 |
private function apply_query_timeout($sql) { |
| 370 |
global $wpdb; |
| 371 |
|
| 372 |
$default = defined('METASYNC_MCP_DB_QUERY_TIMEOUT') |
| 373 |
? (int) METASYNC_MCP_DB_QUERY_TIMEOUT |
| 374 |
: 10; |
| 375 |
$timeout = max(1, (int) apply_filters('mcp_db_query_timeout', $default)); |
| 376 |
|
| 377 |
$server_info = ''; |
| 378 |
if (is_object($wpdb) && method_exists($wpdb, 'db_server_info')) { |
| 379 |
$info = $wpdb->db_server_info(); |
| 380 |
if (is_string($info)) { |
| 381 |
$server_info = $info; |
| 382 |
} |
| 383 |
} |
| 384 |
|
| 385 |
$is_mariadb = $server_info !== '' && stripos($server_info, 'MariaDB') !== false; |
| 386 |
|
| 387 |
if ($is_mariadb) { |
| 388 |
$version = ''; |
| 389 |
if (preg_match('/([0-9]+\.[0-9]+\.[0-9]+)-MariaDB/i', $server_info, $m)) { |
| 390 |
$version = $m[1]; |
| 391 |
} elseif (preg_match('/([0-9]+\.[0-9]+\.[0-9]+)/', $server_info, $m)) { |
| 392 |
$version = $m[1]; |
| 393 |
} |
| 394 |
if ($version !== '' && version_compare($version, '10.1.1', '>=')) { |
| 395 |
// MariaDB uses seconds. SET STATEMENT wraps any statement |
| 396 |
// type, so SELECT / SHOW / DESCRIBE / EXPLAIN are all covered. |
| 397 |
return [ |
| 398 |
'sql' => "SET STATEMENT max_statement_time={$timeout} FOR {$sql}", |
| 399 |
'timeout' => $timeout, |
| 400 |
'mechanism' => 'mariadb', |
| 401 |
]; |
| 402 |
} |
| 403 |
} else { |
| 404 |
$version = ''; |
| 405 |
if (preg_match('/^([0-9]+\.[0-9]+\.[0-9]+)/', $server_info, $m)) { |
| 406 |
$version = $m[1]; |
| 407 |
} |
| 408 |
if ($version !== '' && version_compare($version, '5.7.8', '>=')) { |
| 409 |
// Find the first real keyword (ignoring leading comments) to |
| 410 |
// decide whether the MAX_EXECUTION_TIME hint applies. The |
| 411 |
// hint is only valid for SELECT. |
| 412 |
$stripped = preg_replace( |
| 413 |
'/\A(\s*(\/\*.*?\*\/\s*|--[^\n]*\n?\s*))+/s', |
| 414 |
'', |
| 415 |
$sql |
| 416 |
); |
| 417 |
$first_kw = strtoupper(preg_replace('/[\s(;].*/s', '', $stripped)); |
| 418 |
if ($first_kw === 'SELECT') { |
| 419 |
$ms = $timeout * 1000; |
| 420 |
$leading = substr($sql, 0, strlen($sql) - strlen($stripped)); |
| 421 |
$timeout_sql = $leading |
| 422 |
. substr($stripped, 0, 6) |
| 423 |
. " /*+ MAX_EXECUTION_TIME({$ms}) */" |
| 424 |
. substr($stripped, 6); |
| 425 |
return [ |
| 426 |
'sql' => $timeout_sql, |
| 427 |
'timeout' => $timeout, |
| 428 |
'mechanism' => 'mysql', |
| 429 |
]; |
| 430 |
} |
| 431 |
} |
| 432 |
} |
| 433 |
|
| 434 |
// Unsupported DB version / non-SELECT on MySQL: rely on the PHP-level |
| 435 |
// set_time_limit() fallback applied by the caller. |
| 436 |
return [ |
| 437 |
'sql' => $sql, |
| 438 |
'timeout' => $timeout, |
| 439 |
'mechanism' => 'php_only', |
| 440 |
]; |
| 441 |
} |
| 442 |
} |
| 443 |
|
