Файл: controllers/flatfile_utils.php
Строк: 180
<?php
// Utilities for flatfile functions
/** Constant to indicating a column holding floating point numbers */
define('FLOAT_COL', 'float');
/** Constant to indicating a column holding integers */
define('INT_COL', 'int');
/** Constant to indicating a column holding strings */
define('STRING_COL', 'string');
/** Constant to indicating a column holding unix timestamps */
define('DATE_COL', 'date');
/** EXPERIMENTAL: Encapsulates info about a column in a flatfile DB */
class Column
{
/**
* Create a new column object
*/
function Column($index, $type)
{
$this->index = $index;
$this->type = $type;
}
}
/** EXPERIMENTAL: Represent a column that is a foreign key. Used for temporarily building tables array */
class JoinColumn
{
function JoinColumn($index, $tablename, $columnname)
{
$this->index = $index;
$this->tablename = $tablename;
$this->columnname = $columnname;
}
}
/**
* EXPERIMENTAL: Utilities for handling definitions of tables.
*/
class TableUtils
{
/**
* Finds JoinColumns in an array of tables, and adds 'type' fields by looking up the columns
*
* @param tables This should be an associative array containing 'tablename' => tabledefinition
* tabledefinition is itself an associativive array of 'COLUMN_NAME_CONSTANT' => columndefintion
* COLUMN_NAME_CONSTANT should be a unique constant within the table, and
* column definition should be a Column object or JoinColumn object
*/
function resolveJoins(&$tables)
{
foreach ($tables as $tablename => $discard)
{
// PHP4 compatible: can't do : foreach ($tables as $tablename => &$tabledef)
// and strangely, if we do
// foreach ($tables as $tablename => &$tabledef)
// $tabledef =& $tables[$tablename];
// then we get bugs
$tabledef =& $tables[$tablename];
foreach ($tabledef as $colname => $discard)
{
$coldef =& $tabledef[$colname]; // PHP4 compatible
if (is_a($coldef, 'JoinColumn') or is_subclass_of($coldef, 'JoinColumn'))
{
TableUtils::resolveColumnJoin($coldef, $tables);
}
}
}
}
/** @access private */
function resolveColumnJoin(&$columndef, &$tables)
{
// Doesn't work if the column it is joined to is also
// a JoinColumn, but I can't think of ever wanting to do that
$columndef->type = $tables[$columndef->tablename][$columndef->columnname]->type;
}
/** Uses 'define' to create global constants for all the column names */
function createDefines(&$tables)
{
foreach ($tables as $tablename => $discard)
{
$tabledef = &$tables[$tablename]; // PHP4 compatible
foreach ($tabledef as $colname => $discard)
{
$coldef = &$tabledef[$colname];
define(strtoupper($tablename) . '_' . $colname, $coldef->index);
}
}
}
/**
* Creates a 'row schema' for a given table definition.
*
* A row schema is just an array of the column types for a table,
* using the constants defined above.
*/
function createRowSchema(&$tabledef)
{
$row_schema = array();
foreach ($tabledef as $colname => $coldef)
{
$row_schema[$coldef->index] = $coldef->type;
}
return $row_schema;
}
}
?>