/libraries/Advisor.php
PHP | 547 lines | 335 code | 49 blank | 163 comment | 38 complexity | 9f0d00efea849344cdea003490e5f570 MD5 | raw file
- <?php
- /* vim: set expandtab sw=4 ts=4 sts=4: */
- /**
- * A simple rules engine, that parses and executes the rules in advisory_rules.txt.
- * Adjusted to phpMyAdmin.
- *
- * @package PhpMyAdmin
- */
- namespace PMA\libraries;
- use \Exception;
- use PMA\libraries\URL;
- require_once 'libraries/advisor.lib.php';
- /**
- * Advisor class
- *
- * @package PhpMyAdmin
- */
- class Advisor
- {
- protected $variables;
- protected $parseResult;
- protected $runResult;
- /**
- * Get variables
- *
- * @return mixed
- */
- public function getVariables()
- {
- return $this->variables;
- }
- /**
- * Set variables
- *
- * @param array $variables Variables
- *
- * @return Advisor
- */
- public function setVariables($variables)
- {
- $this->variables = $variables;
- return $this;
- }
- /**
- * Set a variable and its value
- *
- * @param string|int $variable Variable to set
- * @param mixed $value Value to set
- *
- * @return $this
- */
- public function setVariable($variable, $value)
- {
- $this->variables[$variable] = $value;
- return $this;
- }
- /**
- * Get parseResult
- *
- * @return mixed
- */
- public function getParseResult()
- {
- return $this->parseResult;
- }
- /**
- * Set parseResult
- *
- * @param array $parseResult Parse result
- *
- * @return Advisor
- */
- public function setParseResult($parseResult)
- {
- $this->parseResult = $parseResult;
- return $this;
- }
- /**
- * Get runResult
- *
- * @return mixed
- */
- public function getRunResult()
- {
- return $this->runResult;
- }
- /**
- * Set runResult
- *
- * @param array $runResult Run result
- *
- * @return Advisor
- */
- public function setRunResult($runResult)
- {
- $this->runResult = $runResult;
- return $this;
- }
- /**
- * Parses and executes advisor rules
- *
- * @return array with run and parse results
- */
- public function run()
- {
- // HowTo: A simple Advisory system in 3 easy steps.
- // Step 1: Get some variables to evaluate on
- $this->setVariables(
- array_merge(
- $GLOBALS['dbi']->fetchResult('SHOW GLOBAL STATUS', 0, 1),
- $GLOBALS['dbi']->fetchResult('SHOW GLOBAL VARIABLES', 0, 1)
- )
- );
- // Add total memory to variables as well
- include_once 'libraries/sysinfo.lib.php';
- $sysinfo = PMA_getSysInfo();
- $memory = $sysinfo->memory();
- $this->variables['system_memory']
- = isset($memory['MemTotal']) ? $memory['MemTotal'] : 0;
- // Step 2: Read and parse the list of rules
- $this->setParseResult(static::parseRulesFile());
- // Step 3: Feed the variables to the rules and let them fire. Sets
- // $runResult
- $this->runRules();
- return array(
- 'parse' => array('errors' => $this->parseResult['errors']),
- 'run' => $this->runResult
- );
- }
- /**
- * Stores current error in run results.
- *
- * @param string $description description of an error.
- * @param Exception $exception exception raised
- *
- * @return void
- */
- public function storeError($description, $exception)
- {
- $this->runResult['errors'][] = $description
- . ' '
- . sprintf(
- __('PHP threw following error: %s'),
- $exception->getMessage()
- );
- }
- /**
- * Executes advisor rules
- *
- * @return boolean
- */
- public function runRules()
- {
- $this->setRunResult(
- array(
- 'fired' => array(),
- 'notfired' => array(),
- 'unchecked' => array(),
- 'errors' => array(),
- )
- );
- foreach ($this->parseResult['rules'] as $rule) {
- $this->variables['value'] = 0;
- $precond = true;
- if (isset($rule['precondition'])) {
- try {
- $precond = $this->ruleExprEvaluate($rule['precondition']);
- } catch (Exception $e) {
- $this->storeError(
- sprintf(
- __('Failed evaluating precondition for rule \'%s\'.'),
- $rule['name']
- ),
- $e
- );
- continue;
- }
- }
- if (! $precond) {
- $this->addRule('unchecked', $rule);
- } else {
- try {
- $value = $this->ruleExprEvaluate($rule['formula']);
- } catch (Exception $e) {
- $this->storeError(
- sprintf(
- __('Failed calculating value for rule \'%s\'.'),
- $rule['name']
- ),
- $e
- );
- continue;
- }
- $this->variables['value'] = $value;
- try {
- if ($this->ruleExprEvaluate($rule['test'])) {
- $this->addRule('fired', $rule);
- } else {
- $this->addRule('notfired', $rule);
- }
- } catch (Exception $e) {
- $this->storeError(
- sprintf(
- __('Failed running test for rule \'%s\'.'),
- $rule['name']
- ),
- $e
- );
- }
- }
- }
- return true;
- }
- /**
- * Escapes percent string to be used in format string.
- *
- * @param string $str string to escape
- *
- * @return string
- */
- public static function escapePercent($str)
- {
- return preg_replace('/%( |,|\.|$|\(|\)|<|>)/', '%%\1', $str);
- }
- /**
- * Wrapper function for translating.
- *
- * @param string $str the string
- * @param string $param the parameters
- *
- * @return string
- */
- public function translate($str, $param = null)
- {
- $string = _gettext(self::escapePercent($str));
- if (! is_null($param)) {
- $params = $this->ruleExprEvaluate('array(' . $param . ')');
- } else {
- $params = array();
- }
- return vsprintf($string, $params);
- }
- /**
- * Splits justification to text and formula.
- *
- * @param array $rule the rule
- *
- * @return string[]
- */
- public static function splitJustification($rule)
- {
- $jst = preg_split('/\s*\|\s*/', $rule['justification'], 2);
- if (count($jst) > 1) {
- return array($jst[0], $jst[1]);
- }
- return array($rule['justification']);
- }
- /**
- * Adds a rule to the result list
- *
- * @param string $type type of rule
- * @param array $rule rule itself
- *
- * @return void
- */
- public function addRule($type, $rule)
- {
- switch ($type) {
- case 'notfired':
- case 'fired':
- $jst = self::splitJustification($rule);
- if (count($jst) > 1) {
- try {
- /* Translate */
- $str = $this->translate($jst[0], $jst[1]);
- } catch (Exception $e) {
- $this->storeError(
- sprintf(
- __('Failed formatting string for rule \'%s\'.'),
- $rule['name']
- ),
- $e
- );
- return;
- }
- $rule['justification'] = $str;
- } else {
- $rule['justification'] = $this->translate($rule['justification']);
- }
- $rule['id'] = $rule['name'];
- $rule['name'] = $this->translate($rule['name']);
- $rule['issue'] = $this->translate($rule['issue']);
- // Replaces {server_variable} with 'server_variable'
- // linking to server_variables.php
- $rule['recommendation'] = preg_replace(
- '/\{([a-z_0-9]+)\}/Ui',
- '<a href="server_variables.php' . URL::getCommon()
- . '&filter=\1">\1</a>',
- $this->translate($rule['recommendation'])
- );
- // Replaces external Links with PMA_linkURL() generated links
- $rule['recommendation'] = preg_replace_callback(
- '#href=("|\')(https?://[^\1]+)\1#i',
- array($this, 'replaceLinkURL'),
- $rule['recommendation']
- );
- break;
- }
- $this->runResult[$type][] = $rule;
- }
- /**
- * Callback for wrapping links with PMA_linkURL
- *
- * @param array $matches List of matched elements form preg_replace_callback
- *
- * @return string Replacement value
- */
- private function replaceLinkURL($matches)
- {
- return 'href="' . PMA_linkURL($matches[2]) . '" target="_blank"';
- }
- /**
- * Callback for evaluating fired() condition.
- *
- * @param array $matches List of matched elements form preg_replace_callback
- *
- * @return string Replacement value
- */
- private function ruleExprEvaluateFired($matches)
- {
- // No list of fired rules
- if (!isset($this->runResult['fired'])) {
- return '0';
- }
- // Did matching rule fire?
- foreach ($this->runResult['fired'] as $rule) {
- if ($rule['id'] == $matches[2]) {
- return '1';
- }
- }
- return '0';
- }
- /**
- * Callback for evaluating variables in expression.
- *
- * @param array $matches List of matched elements form preg_replace_callback
- *
- * @return string Replacement value
- */
- private function ruleExprEvaluateVariable($matches)
- {
- if (! isset($this->variables[$matches[1]])) {
- return $matches[1];
- }
- if (is_numeric($this->variables[$matches[1]])) {
- return $this->variables[$matches[1]];
- } else {
- return '\'' . addslashes($this->variables[$matches[1]]) . '\'';
- }
- }
- /**
- * Runs a code expression, replacing variable names with their respective
- * values
- *
- * @param string $expr expression to evaluate
- *
- * @return integer result of evaluated expression
- *
- * @throws Exception
- */
- public function ruleExprEvaluate($expr)
- {
- // Evaluate fired() conditions
- $expr = preg_replace_callback(
- '/fired\s*\(\s*(\'|")(.*)\1\s*\)/Ui',
- array($this, 'ruleExprEvaluateFired'),
- $expr
- );
- // Evaluate variables
- $expr = preg_replace_callback(
- '/\b(\w+)\b/',
- array($this, 'ruleExprEvaluateVariable'),
- $expr
- );
- $value = 0;
- $err = 0;
- // Actually evaluate the code
- ob_start();
- try {
- eval('$value = ' . $expr . ';');
- $err = ob_get_contents();
- } catch (Exception $e) {
- // In normal operation, there is just output in the buffer,
- // but when running under phpunit, error in eval raises exception
- $err = $e->getMessage();
- }
- ob_end_clean();
- // Error handling
- if ($err) {
- throw new Exception(
- strip_tags($err)
- . '<br />Executed code: $value = ' . htmlspecialchars($expr) . ';'
- );
- }
- return $value;
- }
- /**
- * Reads the rule file into an array, throwing errors messages on syntax
- * errors.
- *
- * @return array with parsed data
- */
- public static function parseRulesFile()
- {
- $file = file('libraries/advisory_rules.txt', FILE_IGNORE_NEW_LINES);
- $errors = array();
- $rules = array();
- $lines = array();
- $ruleSyntax = array(
- 'name', 'formula', 'test', 'issue', 'recommendation', 'justification'
- );
- $numRules = count($ruleSyntax);
- $numLines = count($file);
- $ruleNo = -1;
- $ruleLine = -1;
- for ($i = 0; $i < $numLines; $i++) {
- $line = $file[$i];
- if ($line == "" || $line[0] == '#') {
- continue;
- }
- // Reading new rule
- if (substr($line, 0, 4) == 'rule') {
- if ($ruleLine > 0) {
- $errors[] = sprintf(
- __(
- 'Invalid rule declaration on line %1$s, expected line '
- . '%2$s of previous rule.'
- ),
- $i + 1,
- $ruleSyntax[$ruleLine++]
- );
- continue;
- }
- if (preg_match("/rule\s'(.*)'( \[(.*)\])?$/", $line, $match)) {
- $ruleLine = 1;
- $ruleNo++;
- $rules[$ruleNo] = array('name' => $match[1]);
- $lines[$ruleNo] = array('name' => $i + 1);
- if (isset($match[3])) {
- $rules[$ruleNo]['precondition'] = $match[3];
- $lines[$ruleNo]['precondition'] = $i + 1;
- }
- } else {
- $errors[] = sprintf(
- __('Invalid rule declaration on line %s.'),
- $i + 1
- );
- }
- continue;
- } else {
- if ($ruleLine == -1) {
- $errors[] = sprintf(
- __('Unexpected characters on line %s.'),
- $i + 1
- );
- }
- }
- // Reading rule lines
- if ($ruleLine > 0) {
- if (!isset($line[0])) {
- continue; // Empty lines are ok
- }
- // Non tabbed lines are not
- if ($line[0] != "\t") {
- $errors[] = sprintf(
- __(
- 'Unexpected character on line %1$s. Expected tab, but '
- . 'found "%2$s".'
- ),
- $i + 1,
- $line[0]
- );
- continue;
- }
- $rules[$ruleNo][$ruleSyntax[$ruleLine]] = chop(
- mb_substr($line, 1)
- );
- $lines[$ruleNo][$ruleSyntax[$ruleLine]] = $i + 1;
- ++$ruleLine;
- }
- // Rule complete
- if ($ruleLine == $numRules) {
- $ruleLine = -1;
- }
- }
- return array('rules' => $rules, 'lines' => $lines, 'errors' => $errors);
- }
- }