85dd699364
Fixes #11956. unrecognized keyword interval Fixes issues regarding field names and aliases. Signed-off-by: Dan Ungureanu <udan1107@gmail.com>
436 lines
14 KiB
PHP
436 lines
14 KiB
PHP
<?php
|
|
|
|
/**
|
|
* Parses a reference to an expression (column, table or database name, function
|
|
* call, mathematical expression, etc.).
|
|
*
|
|
* @package SqlParser
|
|
* @subpackage Components
|
|
*/
|
|
namespace SqlParser\Components;
|
|
|
|
use SqlParser\Context;
|
|
use SqlParser\Component;
|
|
use SqlParser\Parser;
|
|
use SqlParser\Token;
|
|
use SqlParser\TokensList;
|
|
|
|
/**
|
|
* Parses a reference to an expression (column, table or database name, function
|
|
* call, mathematical expression, etc.).
|
|
*
|
|
* @category Components
|
|
* @package SqlParser
|
|
* @subpackage Components
|
|
* @author Dan Ungureanu <udan1107@gmail.com>
|
|
* @license http://opensource.org/licenses/GPL-2.0 GNU Public License
|
|
*/
|
|
class Expression extends Component
|
|
{
|
|
|
|
/**
|
|
* List of allowed reserved keywords in expressions.
|
|
*
|
|
* @var array
|
|
*/
|
|
private static $ALLOWED_KEYWORDS = array(
|
|
'AS' => 1, 'DUAL' => 1, 'NULL' => 1, 'REGEXP' => 1
|
|
);
|
|
|
|
/**
|
|
* The name of this database.
|
|
*
|
|
* @var string
|
|
*/
|
|
public $database;
|
|
|
|
/**
|
|
* The name of this table.
|
|
*
|
|
* @var string
|
|
*/
|
|
public $table;
|
|
|
|
/**
|
|
* The name of the column.
|
|
*
|
|
* @var string
|
|
*/
|
|
public $column;
|
|
|
|
/**
|
|
* The sub-expression.
|
|
*
|
|
* @var string
|
|
*/
|
|
public $expr = '';
|
|
|
|
/**
|
|
* The alias of this expression.
|
|
*
|
|
* @var string
|
|
*/
|
|
public $alias;
|
|
|
|
/**
|
|
* The name of the function.
|
|
*
|
|
* @var mixed
|
|
*/
|
|
public $function;
|
|
|
|
/**
|
|
* The type of subquery.
|
|
*
|
|
* @var string
|
|
*/
|
|
public $subquery;
|
|
|
|
/**
|
|
* Constructor.
|
|
*
|
|
* Syntax:
|
|
* new Expression('expr')
|
|
* new Expression('expr', 'alias')
|
|
* new Expression('database', 'table', 'column')
|
|
* new Expression('database', 'table', 'column', 'alias')
|
|
*
|
|
* If the database, table or column name is not required, pass an empty
|
|
* string.
|
|
*
|
|
* @param string $database The name of the database or the the expression.
|
|
* the the expression.
|
|
* @param string $table The name of the table or the alias of the expression.
|
|
* the alias of the expression.
|
|
* @param string $column The name of the column.
|
|
* @param string $alias The name of the alias.
|
|
*/
|
|
public function __construct($database = null, $table = null, $column = null, $alias = null)
|
|
{
|
|
if (($column === null) && ($alias === null)) {
|
|
$this->expr = $database; // case 1
|
|
$this->alias = $table; // case 2
|
|
} else {
|
|
$this->database = $database; // case 3
|
|
$this->table = $table; // case 3
|
|
$this->column = $column; // case 3
|
|
$this->alias = $alias; // case 4
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Possible options:
|
|
*
|
|
* `field`
|
|
*
|
|
* First field to be filled.
|
|
* If this is not specified, it takes the value of `parseField`.
|
|
*
|
|
* `parseField`
|
|
*
|
|
* Specifies the type of the field parsed. It may be `database`,
|
|
* `table` or `column`. These expressions may not include
|
|
* parentheses.
|
|
*
|
|
* `breakOnAlias`
|
|
*
|
|
* If not empty, breaks when the alias occurs (it is not included).
|
|
*
|
|
* `breakOnParentheses`
|
|
*
|
|
* If not empty, breaks when the first parentheses occurs.
|
|
*
|
|
* `parenthesesDelimited`
|
|
*
|
|
* If not empty, breaks after last parentheses occurred.
|
|
*
|
|
* @param Parser $parser The parser that serves as context.
|
|
* @param TokensList $list The list of tokens that are being parsed.
|
|
* @param array $options Parameters for parsing.
|
|
*
|
|
* @return Expression
|
|
*/
|
|
public static function parse(Parser $parser, TokensList $list, array $options = array())
|
|
{
|
|
$ret = new Expression();
|
|
|
|
/**
|
|
* Whether current tokens make an expression or a table reference.
|
|
*
|
|
* @var bool $isExpr
|
|
*/
|
|
$isExpr = false;
|
|
|
|
/**
|
|
* Whether a period was previously found.
|
|
*
|
|
* @var bool $dot
|
|
*/
|
|
$dot = false;
|
|
|
|
/**
|
|
* Whether an alias is expected. Is 2 if `AS` keyword was found.
|
|
*
|
|
* @var bool $alias
|
|
*/
|
|
$alias = false;
|
|
|
|
/**
|
|
* Counts brackets.
|
|
*
|
|
* @var int $brackets
|
|
*/
|
|
$brackets = 0;
|
|
|
|
/**
|
|
* Keeps track of the last two previous tokens.
|
|
*
|
|
* @var Token[] $prev
|
|
*/
|
|
$prev = array(null, null);
|
|
|
|
// When a field is parsed, no parentheses are expected.
|
|
if (!empty($options['parseField'])) {
|
|
$options['breakOnParentheses'] = true;
|
|
$options['field'] = $options['parseField'];
|
|
}
|
|
|
|
for (; $list->idx < $list->count; ++$list->idx) {
|
|
|
|
/**
|
|
* Token parsed at this moment.
|
|
*
|
|
* @var Token $token
|
|
*/
|
|
$token = $list->tokens[$list->idx];
|
|
|
|
// End of statement.
|
|
if ($token->type === Token::TYPE_DELIMITER) {
|
|
break;
|
|
}
|
|
|
|
// Skipping whitespaces and comments.
|
|
if (($token->type === Token::TYPE_WHITESPACE)
|
|
|| ($token->type === Token::TYPE_COMMENT)
|
|
) {
|
|
if ($isExpr) {
|
|
$ret->expr .= $token->token;
|
|
}
|
|
continue;
|
|
}
|
|
|
|
if ($token->type === Token::TYPE_KEYWORD) {
|
|
if (($brackets > 0) && (empty($ret->subquery))
|
|
&& (!empty(Parser::$STATEMENT_PARSERS[$token->value]))
|
|
) {
|
|
// A `(` was previously found and this keyword is the
|
|
// beginning of a statement, so this is a subquery.
|
|
$ret->subquery = $token->value;
|
|
} elseif (($token->flags & Token::FLAG_KEYWORD_FUNCTION)
|
|
&& (empty($options['parseField']))
|
|
) {
|
|
$isExpr = true;
|
|
} elseif (($token->flags & Token::FLAG_KEYWORD_RESERVED)
|
|
&& ($brackets === 0)
|
|
) {
|
|
if (empty(self::$ALLOWED_KEYWORDS[$token->value])) {
|
|
// A reserved keyword that is not allowed in the
|
|
// expression was found so the expression must have
|
|
// ended and a new clause is starting.
|
|
break;
|
|
}
|
|
if ($token->value === 'AS') {
|
|
if (!empty($options['breakOnAlias'])) {
|
|
break;
|
|
}
|
|
if (!empty($ret->alias)) {
|
|
$parser->error(
|
|
__('An alias was previously found.'),
|
|
$token
|
|
);
|
|
break;
|
|
}
|
|
$alias = true;
|
|
continue;
|
|
}
|
|
$isExpr = true;
|
|
}
|
|
}
|
|
|
|
if (($token->type === Token::TYPE_NUMBER)
|
|
|| ($token->type === Token::TYPE_BOOL)
|
|
|| (($token->type === Token::TYPE_SYMBOL)
|
|
&& ($token->flags & Token::FLAG_SYMBOL_VARIABLE))
|
|
|| (($token->type === Token::TYPE_OPERATOR)
|
|
&& ($token->value !== '.'))
|
|
) {
|
|
if (!empty($options['parseField'])) {
|
|
break;
|
|
}
|
|
|
|
// Numbers, booleans and operators (except dot) are usually part
|
|
// of expressions.
|
|
$isExpr = true;
|
|
}
|
|
|
|
if ($token->type === Token::TYPE_OPERATOR) {
|
|
if ((!empty($options['breakOnParentheses']))
|
|
&& (($token->value === '(') || ($token->value === ')'))
|
|
) {
|
|
// No brackets were expected.
|
|
break;
|
|
}
|
|
if ($token->value === '(') {
|
|
++$brackets;
|
|
if ((empty($ret->function)) && ($prev[1] !== null)
|
|
&& (($prev[1]->type === Token::TYPE_NONE)
|
|
|| ($prev[1]->type === Token::TYPE_SYMBOL)
|
|
|| (($prev[1]->type === Token::TYPE_KEYWORD)
|
|
&& ($prev[1]->flags & Token::FLAG_KEYWORD_FUNCTION)))
|
|
) {
|
|
$ret->function = $prev[1]->value;
|
|
}
|
|
} elseif ($token->value === ')') {
|
|
--$brackets;
|
|
if ($brackets === 0) {
|
|
if (!empty($options['parenthesesDelimited'])) {
|
|
// The current token is the last bracket, the next
|
|
// one will be outside the expression.
|
|
$ret->expr .= $token->token;
|
|
++$list->idx;
|
|
break;
|
|
}
|
|
} elseif ($brackets < 0) {
|
|
// $parser->error(__('Unexpected closing bracket.'), $token);
|
|
// $brackets = 0;
|
|
break;
|
|
}
|
|
} elseif ($token->value === ',') {
|
|
// Expressions are comma-delimited.
|
|
if ($brackets === 0) {
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Saving the previous tokens.
|
|
$prev[0] = $prev[1];
|
|
$prev[1] = $token;
|
|
|
|
if ($alias) {
|
|
// An alias is expected (the keyword `AS` was previously found).
|
|
if (!empty($ret->alias)) {
|
|
$parser->error(__('An alias was previously found.'), $token);
|
|
break;
|
|
}
|
|
$ret->alias = $token->value;
|
|
$alias = false;
|
|
} elseif ($isExpr) {
|
|
// Handling aliases.
|
|
if (/* (empty($ret->alias)) && */ ($brackets === 0)
|
|
&& (($prev[0] === null)
|
|
|| ((($prev[0]->type !== Token::TYPE_OPERATOR)
|
|
|| ($prev[0]->token === ')'))
|
|
&& (($prev[0]->type !== Token::TYPE_KEYWORD)
|
|
|| (!($prev[0]->flags & Token::FLAG_KEYWORD_RESERVED)))))
|
|
&& (($prev[1]->type === Token::TYPE_STRING)
|
|
|| (($prev[1]->type === Token::TYPE_SYMBOL)
|
|
&& (!($prev[1]->flags & Token::FLAG_SYMBOL_VARIABLE)))
|
|
|| ($prev[1]->type === Token::TYPE_NONE))
|
|
) {
|
|
if (!empty($ret->alias)) {
|
|
$parser->error(__('An alias was previously found.'), $token);
|
|
break;
|
|
}
|
|
$ret->alias = $prev[1]->value;
|
|
} else {
|
|
$ret->expr .= $token->token;
|
|
}
|
|
} elseif (!$isExpr) {
|
|
if (($token->type === Token::TYPE_OPERATOR) && ($token->value === '.')) {
|
|
// Found a `.` which means we expect a column name and
|
|
// the column name we parsed is actually the table name
|
|
// and the table name is actually a database name.
|
|
if ((!empty($ret->database)) || ($dot)) {
|
|
$parser->error(__('Unexpected dot.'), $token);
|
|
}
|
|
$ret->database = $ret->table;
|
|
$ret->table = $ret->column;
|
|
$ret->column = null;
|
|
$dot = true;
|
|
$ret->expr .= $token->token;
|
|
} else {
|
|
$field = empty($options['field']) ? 'column' : $options['field'];
|
|
if (empty($ret->$field)) {
|
|
$ret->$field = $token->value;
|
|
$ret->expr .= $token->token;
|
|
$dot = false;
|
|
} else {
|
|
// No alias is expected.
|
|
if (!empty($options['breakOnAlias'])) {
|
|
break;
|
|
}
|
|
if (!empty($ret->alias)) {
|
|
$parser->error(__('An alias was previously found.'), $token);
|
|
break;
|
|
}
|
|
$ret->alias = $token->value;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
if ($alias) {
|
|
$parser->error(
|
|
__('An alias was expected.'),
|
|
$list->tokens[$list->idx - 1]
|
|
);
|
|
}
|
|
|
|
// White-spaces might be added at the end.
|
|
$ret->expr = trim($ret->expr);
|
|
|
|
if (empty($ret->expr)) {
|
|
return null;
|
|
}
|
|
|
|
--$list->idx;
|
|
return $ret;
|
|
}
|
|
|
|
/**
|
|
* @param Expression|Expression[] $component The component to be built.
|
|
* @param array $options Parameters for building.
|
|
*
|
|
* @return string
|
|
*/
|
|
public static function build($component, array $options = array())
|
|
{
|
|
if (is_array($component)) {
|
|
return implode($component, ', ');
|
|
} else {
|
|
if (!empty($component->expr)) {
|
|
$ret = $component->expr;
|
|
} else {
|
|
$fields = array();
|
|
if ((isset($component->database)) && ($component->database !== '')) {
|
|
$fields[] = $component->database;
|
|
}
|
|
if ((isset($component->table)) && ($component->table !== '')) {
|
|
$fields[] = $component->table;
|
|
}
|
|
if ((isset($component->column)) && ($component->column !== '')) {
|
|
$fields[] = $component->column;
|
|
}
|
|
$ret = implode('.', Context::escape($fields));
|
|
}
|
|
|
|
if (!empty($component->alias)) {
|
|
$ret .= ' AS ' . Context::escape($component->alias);
|
|
}
|
|
|
|
return $ret;
|
|
}
|
|
}
|
|
}
|
