<?php /** * @link http://www.yiiframework.com/ * @copyright Copyright (c) 2008 Yii Software LLC * @license http://www.yiiframework.com/license/ */ namespace yii\redis; use yii\base\NotSupportedException; use yii\db\Exception; use yii\db\Expression; /** * LuaScriptBuilder builds lua scripts used for retrieving data from redis. * * @author Carsten Brandt <mail@cebe.cc> * @since 2.0 */ class LuaScriptBuilder extends \yii\base\Object { /** * Builds a Lua script for finding a list of records * @param ActiveQuery $query the query used to build the script * @return string */ public function buildAll($query) { // TODO add support for orderBy /** @var ActiveRecord $modelClass */ $modelClass = $query->modelClass; $key = $this->quoteValue($modelClass::keyPrefix() . ':a:'); return $this->build($query, "n=n+1 pks[n]=redis.call('HGETALL',$key .. pk)", 'pks'); } /** * Builds a Lua script for finding one record * @param ActiveQuery $query the query used to build the script * @return string */ public function buildOne($query) { // TODO add support for orderBy /** @var ActiveRecord $modelClass */ $modelClass = $query->modelClass; $key = $this->quoteValue($modelClass::keyPrefix() . ':a:'); return $this->build($query, "do return redis.call('HGETALL',$key .. pk) end", 'pks'); } /** * Builds a Lua script for finding a column * @param ActiveQuery $query the query used to build the script * @param string $column name of the column * @return string */ public function buildColumn($query, $column) { // TODO add support for orderBy and indexBy /** @var ActiveRecord $modelClass */ $modelClass = $query->modelClass; $key = $this->quoteValue($modelClass::keyPrefix() . ':a:'); return $this->build($query, "n=n+1 pks[n]=redis.call('HGET',$key .. pk," . $this->quoteValue($column) . ")", 'pks'); } /** * Builds a Lua script for getting count of records * @param ActiveQuery $query the query used to build the script * @return string */ public function buildCount($query) { return $this->build($query, 'n=n+1', 'n'); } /** * Builds a Lua script for finding the sum of a column * @param ActiveQuery $query the query used to build the script * @param string $column name of the column * @return string */ public function buildSum($query, $column) { /** @var ActiveRecord $modelClass */ $modelClass = $query->modelClass; $key = $this->quoteValue($modelClass::keyPrefix() . ':a:'); return $this->build($query, "n=n+redis.call('HGET',$key .. pk," . $this->quoteValue($column) . ")", 'n'); } /** * Builds a Lua script for finding the average of a column * @param ActiveQuery $query the query used to build the script * @param string $column name of the column * @return string */ public function buildAverage($query, $column) { /** @var ActiveRecord $modelClass */ $modelClass = $query->modelClass; $key = $this->quoteValue($modelClass::keyPrefix() . ':a:'); return $this->build($query, "n=n+1 if v==nil then v=0 end v=v+redis.call('HGET',$key .. pk," . $this->quoteValue($column) . ")", 'v/n'); } /** * Builds a Lua script for finding the min value of a column * @param ActiveQuery $query the query used to build the script * @param string $column name of the column * @return string */ public function buildMin($query, $column) { /** @var ActiveRecord $modelClass */ $modelClass = $query->modelClass; $key = $this->quoteValue($modelClass::keyPrefix() . ':a:'); return $this->build($query, "n=redis.call('HGET',$key .. pk," . $this->quoteValue($column) . ") if v==nil or n<v then v=n end", 'v'); } /** * Builds a Lua script for finding the max value of a column * @param ActiveQuery $query the query used to build the script * @param string $column name of the column * @return string */ public function buildMax($query, $column) { /** @var ActiveRecord $modelClass */ $modelClass = $query->modelClass; $key = $this->quoteValue($modelClass::keyPrefix() . ':a:'); return $this->build($query, "n=redis.call('HGET',$key .. pk," . $this->quoteValue($column) . ") if v==nil or n>v then v=n end", 'v'); } /** * @param ActiveQuery $query the query used to build the script * @param string $buildResult the lua script for building the result * @param string $return the lua variable that should be returned * @return string */ private function build($query, $buildResult, $return) { if (!empty($query->orderBy)) { throw new NotSupportedException('orderBy is currently not supported by redis ActiveRecord.'); } $columns = []; if ($query->where !== null) { $condition = $this->buildCondition($query->where, $columns); } else { $condition = 'true'; } $start = $query->offset === null ? 0 : $query->offset; $limitCondition = 'i>' . $start . ($query->limit === null ? '' : ' and i<=' . ($start + $query->limit)); /** @var ActiveRecord $modelClass */ $modelClass = $query->modelClass; $key = $this->quoteValue($modelClass::keyPrefix()); $loadColumnValues = ''; foreach($columns as $column => $alias) { $loadColumnValues .= "local $alias=redis.call('HGET',$key .. ':a:' .. pk, '$column')\n"; } return <<<EOF local allpks=redis.call('LRANGE',$key,0,-1) local pks={} local n=0 local v=nil local i=0 for k,pk in ipairs(allpks) do $loadColumnValues if $condition then i=i+1 if $limitCondition then $buildResult end end end return $return EOF; } /** * Adds a column to the list of columns to retrieve and creates an alias * @param string $column the column name to add * @param array $columns list of columns given by reference * @return string the alias generated for the column name */ private function addColumn($column, &$columns) { if (isset($columns[$column])) { return $columns[$column]; } $name = 'c' . preg_replace("/[^A-z]+/", "", $column) . count($columns); return $columns[$column] = $name; } /** * Quotes a string value for use in a query. * Note that if the parameter is not a string or int, it will be returned without change. * @param string $str string to be quoted * @return string the properly quoted string */ private function quoteValue($str) { if (!is_string($str) && !is_int($str)) { return $str; } return "'" . addcslashes(str_replace("'", "\\'", $str), "\000\n\r\\\032") . "'"; } /** * Parses the condition specification and generates the corresponding Lua expression. * @param string|array $condition the condition specification. Please refer to [[ActiveQuery::where()]] * on how to specify a condition. * @param array $columns the list of columns and aliases to be used * @return string the generated SQL expression * @throws \yii\db\Exception if the condition is in bad format * @throws \yii\base\NotSupportedException if the condition is not an array */ public function buildCondition($condition, &$columns) { static $builders = [ 'and' => 'buildAndCondition', 'or' => 'buildAndCondition', 'between' => 'buildBetweenCondition', 'not between' => 'buildBetweenCondition', 'in' => 'buildInCondition', 'not in' => 'buildInCondition', 'like' => 'buildLikeCondition', 'not like' => 'buildLikeCondition', 'or like' => 'buildLikeCondition', 'or not like' => 'buildLikeCondition', ]; if (!is_array($condition)) { throw new NotSupportedException('Where condition must be an array in redis ActiveRecord.'); } if (isset($condition[0])) { // operator format: operator, operand 1, operand 2, ... $operator = strtolower($condition[0]); if (isset($builders[$operator])) { $method = $builders[$operator]; array_shift($condition); return $this->$method($operator, $condition, $columns); } else { throw new Exception('Found unknown operator in query: ' . $operator); } } else { // hash format: 'column1' => 'value1', 'column2' => 'value2', ... return $this->buildHashCondition($condition, $columns); } } private function buildHashCondition($condition, &$columns) { $parts = []; foreach ($condition as $column => $value) { if (is_array($value)) { // IN condition $parts[] = $this->buildInCondition('in', [$column, $value], $columns); } else { $column = $this->addColumn($column, $columns); if ($value === null) { $parts[] = "$column==nil"; } elseif ($value instanceof Expression) { $parts[] = "$column==" . $value->expression; } else { $value = $this->quoteValue($value); $parts[] = "$column==$value"; } } } return count($parts) === 1 ? $parts[0] : '(' . implode(') and (', $parts) . ')'; } private function buildAndCondition($operator, $operands, &$columns) { $parts = []; foreach ($operands as $operand) { if (is_array($operand)) { $operand = $this->buildCondition($operand, $columns); } if ($operand !== '') { $parts[] = $operand; } } if (!empty($parts)) { return '(' . implode(") $operator (", $parts) . ')'; } else { return ''; } } private function buildBetweenCondition($operator, $operands, &$columns) { if (!isset($operands[0], $operands[1], $operands[2])) { throw new Exception("Operator '$operator' requires three operands."); } list($column, $value1, $value2) = $operands; $value1 = $this->quoteValue($value1); $value2 = $this->quoteValue($value2); $column = $this->addColumn($column, $columns); return "$column >= $value1 and $column <= $value2"; } private function buildInCondition($operator, $operands, &$columns) { if (!isset($operands[0], $operands[1])) { throw new Exception("Operator '$operator' requires two operands."); } list($column, $values) = $operands; $values = (array)$values; if (empty($values) || $column === []) { return $operator === 'in' ? 'false' : 'true'; } if (count($column) > 1) { return $this->buildCompositeInCondition($operator, $column, $values, $columns); } elseif (is_array($column)) { $column = reset($column); } $columnAlias = $this->addColumn($column, $columns); $parts = []; foreach ($values as $i => $value) { if (is_array($value)) { $value = isset($value[$column]) ? $value[$column] : null; } if ($value === null) { $parts[] = "$columnAlias==nil"; } elseif ($value instanceof Expression) { $parts[] = "$columnAlias==" . $value->expression; } else { $value = $this->quoteValue($value); $parts[] = "$columnAlias==$value"; } } $operator = $operator === 'in' ? '' : 'not '; return "$operator(" . implode(' or ', $parts) . ')'; } protected function buildCompositeInCondition($operator, $inColumns, $values, &$columns) { $vss = []; foreach ($values as $value) { $vs = []; foreach ($inColumns as $column) { $column = $this->addColumn($column, $columns); if (isset($value[$column])) { $vs[] = "$column==" . $this->quoteValue($value[$column]); } else { $vs[] = "$column==nil"; } } $vss[] = '(' . implode(' and ', $vs) . ')'; } $operator = $operator === 'in' ? '' : 'not '; return "$operator(" . implode(' or ', $vss) . ')'; } private function buildLikeCondition($operator, $operands, &$columns) { throw new NotSupportedException('LIKE conditions are not suppoerted by redis ActiveRecord.'); } }