PostgresSchema.php

<?php
/**
 * PHP Version 5.4
 *
 * CakePHP(tm) : Rapid Development Framework (http://cakephp.org)
 * Copyright (c) Cake Software Foundation, Inc. (http://cakefoundation.org)
 *
 * Licensed under The MIT License
 * For full copyright and license information, please see the LICENSE.txt
 * Redistributions of files must retain the above copyright notice.
 *
 * @copyright     Copyright (c) Cake Software Foundation, Inc. (http://cakefoundation.org)
 * @link          http://cakephp.org CakePHP(tm) Project
 * @since         CakePHP(tm) v 3.0.0
 * @license       MIT License (http://www.opensource.org/licenses/mit-license.php)
 */
namespace Cake\Database\Schema;

use Cake\Database\Schema\Table;
use Cake\Error;

/**
 * Schema management/reflection features for Postgres.
 */
class PostgresSchema {

/**
 * The driver instance being used.
 *
 * @var Cake\Database\Driver\Postgres
 */
	protected $_driver;

/**
 * Constructor
 *
 * @param Cake\Database\Driver\Postgres $driver Driver to use.
 * @return void
 */
	public function __construct($driver) {
		$this->_driver = $driver;
	}

/**
 * Get the SQL to list the tables
 *
 * @param array $config The connection configuration to use for
 *    getting tables from.
 * @return array An array of (sql, params) to execute.
 */
	public function listTablesSql($config) {
		$sql = "SELECT table_name as name FROM INFORMATION_SCHEMA.tables WHERE table_schema = ? ORDER BY name";
		$schema = empty($config['schema']) ? 'public' : $config['schema'];
		return [$sql, [$schema]];
	}

/**
 * Get the SQL to describe a table in Postgres.
 *
 * @param string $table The table name to describe
 * @param array $config The connection configuration to use
 * @return array An array of (sql, params) to execute.
 */
	public function describeTableSql($table, $config) {
		$sql =
		"SELECT DISTINCT table_schema AS schema, column_name AS name, data_type AS type,
			is_nullable AS null, column_default AS default, ordinal_position AS position,
			character_maximum_length AS char_length, character_octet_length AS oct_length,
			d.description as comment, i.indisprimary = 't' as pk
		FROM information_schema.columns c
		INNER JOIN pg_catalog.pg_namespace ns ON (ns.nspname = table_schema)
		INNER JOIN pg_catalog.pg_class cl ON (cl.relnamespace = ns.oid AND cl.relname = table_name)
		LEFT JOIN pg_catalog.pg_index i ON (i.indrelid = cl.oid AND i.indkey[0] = c.ordinal_position)
		LEFT JOIN pg_catalog.pg_description d on (cl.oid = d.objoid AND d.objsubid = c.ordinal_position)
		WHERE table_name = ? AND table_schema = ?  ORDER BY position";
		$schema = empty($config['schema']) ? 'public' : $config['schema'];
		return [$sql, [$table, $schema]];
	}

/**
 * Convert a column definition to the abstract types.
 *
 * The returned type will be a type that
 * Cake\Database\Type can handle.
 *
 * @param string $column The column type + length
 * @throws Cake\Error\Exception when column cannot be parsed.
 * @return array Array of column information.
 */
	public function convertColumn($column) {
		preg_match('/([a-z\s]+)(?:\(([0-9,]+)\))?/i', $column, $matches);
		if (empty($matches)) {
			throw new Error\Exception(__d('cake_dev', 'Unable to parse column type from "%s"', $column));
		}

		$col = strtolower($matches[1]);
		$length = null;
		if (isset($matches[2])) {
			$length = (int)$matches[2];
		}

		if (in_array($col, array('date', 'time', 'boolean'))) {
			return ['type' => $col, 'length' => null];
		}
		if (strpos($col, 'timestamp') !== false) {
			return ['type' => 'datetime', 'length' => null];
		}
		if ($col === 'serial' || $col === 'integer') {
			return ['type' => 'integer', 'length' => 10];
		}
		if ($col === 'bigserial' || $col === 'bigint') {
			return ['type' => 'biginteger', 'length' => 20];
		}
		if ($col === 'smallint') {
			return ['type' => 'integer', 'length' => 5];
		}
		if ($col === 'inet') {
			return ['type' => 'string', 'length' => 39];
		}
		if ($col === 'uuid') {
			return ['type' => 'string', 'fixed' => true, 'length' => 36];
		}
		if ($col === 'char' || $col === 'character') {
			return ['type' => 'string', 'fixed' => true, 'length' => $length];
		}
		if (strpos($col, 'char') !== false) {
			return ['type' => 'string', 'length' => $length];
		}
		if (strpos($col, 'text') !== false) {
			return ['type' => 'text', 'length' => null];
		}
		if ($col === 'bytea') {
			return ['type' => 'binary', 'length' => null];
		}
		if ($col === 'real' || strpos($col, 'double') !== false) {
			return ['type' => 'float', 'length' => null];
		}
		if (
			strpos($col, 'numeric') !== false ||
			strpos($col, 'money') !== false ||
			strpos($col, 'decimal') !== false
		) {
			return ['type' => 'decimal', 'length' => null];
		}
		return ['type' => 'text', 'length' => null];
	}

/**
 * Convert field description results into abstract schema fields.
 *
 * @param Cake\Database\Schema\Table $table The table object to append fields to.
 * @param array $row The row data from describeTableSql
 * @param array $fieldParams Additional field parameters to parse.
 * @return void
 */
	public function convertFieldDescription(Table $table, $row, $fieldParams = []) {
		$field = $this->convertColumn($row['type']);

		if ($field['type'] === 'boolean') {
			if ($row['default'] === 'true') {
				$row['default'] = 1;
			}
			if ($row['default'] === 'false') {
				$row['default'] = 0;
			}
		}

		$field += [
			'null' => $row['null'] === 'YES' ? true : false,
			'default' => $row['default'],
		];
		$field['length'] = $row['char_length'] ?: $field['length'];
		foreach ($fieldParams as $key => $metadata) {
			if (!empty($row[$metadata['column']])) {
				$field[$key] = $row[$metadata['column']];
			}
		}
		$table->addColumn($row['name'], $field);
		if (!empty($row['pk'])) {
			$table->addConstraint('primary', [
				'type' => Table::CONSTRAINT_PRIMARY,
				'columns' => [$row['name']]
			]);
		}
	}

/**
 * Generate the SQL fragment for a single column.
 *
 * @param Cake\Database\Schema\Table $table The table object the column is in.
 * @param string $name The name of the column.
 * @return string SQL fragment.
 */
	public function columnSql(Table $table, $name) {
		$data = $table->column($name);
		$out = $this->_driver->quoteIdentifier($name);
		$typeMap = [
			'biginteger' => ' BIGINT',
			'boolean' => ' BOOLEAN',
			'binary' => ' BYTEA',
			'float' => ' FLOAT',
			'decimal' => ' DECIMAL',
			'text' => ' TEXT',
			'date' => ' DATE',
			'time' => ' TIME',
			'datetime' => ' TIMESTAMP',
			'timestamp' => ' TIMESTAMP',
		];

		if (isset($typeMap[$data['type']])) {
			$out .= $typeMap[$data['type']];
		}

		if ($data['type'] === 'integer') {
			$type = ' INTEGER';
			if (in_array($name, (array)$table->primaryKey())) {
				$type = ' SERIAL';
				unset($data['null'], $data['default']);
			}
			$out .= $type;
		}

		if ($data['type'] === 'string') {
			$isFixed = !empty($data['fixed']);
			$type = ' VARCHAR';
			if ($isFixed) {
				$type = ' CHAR';
			}
			if ($isFixed && isset($data['length']) && $data['length'] == 36) {
				$type = ' UUID';
			}
			$out .= $type;
			if (isset($data['length']) && $data['length'] != 36) {
				$out .= '(' . (int)$data['length'] . ')';
			}
		}

		if ($data['type'] === 'float' && isset($data['precision'])) {
			$out .= '(' . (int)$data['precision'] . ')';
		}

		if ($data['type'] === 'decimal' &&
			(isset($data['length']) || isset($data['precision']))
		) {
			$out .= '(' . (int)$data['length'] . ',' . (int)$data['precision'] . ')';
		}

		if (isset($data['null']) && $data['null'] === false) {
			$out .= ' NOT NULL';
		}
		if (isset($data['null']) && $data['null'] === true) {
			$out .= ' DEFAULT NULL';
			unset($data['default']);
		}
		if (isset($data['default']) && $data['type'] !== 'timestamp') {
			$out .= ' DEFAULT ' . $this->_driver->schemaValue($data['default']);
		}
		return $out;
	}

/**
 * Generate the SQL fragment for a single index
 *
 * @param Cake\Database\Schema\Table $table The table object the column is in.
 * @param string $name The name of the column.
 * @return string SQL fragment.
 */
	public function indexSql(Table $table, $name) {
		$data = $table->index($name);
		$columns = array_map(
			[$this->_driver, 'quoteIdentifier'],
			$data['columns']
		);
		return sprintf('CREATE INDEX %s ON %s (%s)',
			$this->_driver->quoteIdentifier($name),
			$this->_driver->quoteIdentifier($table->name()),
			implode(', ', $columns)
		);
	}

/**
 * Generate the SQL fragment for a single constraint
 *
 * @param Cake\Database\Schema\Table $table The table object the column is in.
 * @param string $name The name of the column.
 * @return string SQL fragment.
 */
	public function constraintSql(Table $table, $name) {
		$data = $table->constraint($name);
		$out = 'CONSTRAINT ' . $this->_driver->quoteIdentifier($name);
		if ($data['type'] === Table::CONSTRAINT_PRIMARY) {
			$out = 'PRIMARY KEY ';
		}
		if ($data['type'] === Table::CONSTRAINT_UNIQUE) {
			$out .= ' UNIQUE ';
		}
		$columns = array_map(
			[$this->_driver, 'quoteIdentifier'],
			$data['columns']
		);
		return $out . '(' . implode(', ', $columns) . ')';
	}

/**
 * Generate the SQL to create a table.
 *
 * @param string $table The name of the table.
 * @param array $columns The columns to go inside the table.
 * @param array $constraints The constraints for the table.
 * @param array $indexes The indexes for the table.
 * @return string A complete CREATE TABLE statement
 */
	public function createTableSql($table, $columns, $constraints, $indexes) {
		$content = array_merge($columns, $constraints);
		$content = implode(",\n", array_filter($content));
		$tableName = $this->_driver->quoteIdentifier($table->name());
		$out = [];
		$out[] = sprintf("CREATE TABLE %s (\n%s\n)", $tableName, $content);
		foreach ($indexes as $index) {
			$out[] = $index;
		}
		foreach ($table->columns() as $column) {
			$columnData = $table->column($column);
			if (isset($columnData['comment'])) {
				$out[] = sprintf('COMMENT ON COLUMN %s.%s IS %s',
					$tableName,
					$this->_driver->quoteIdentifier($column),
					$this->_driver->schemaValue($columnData['comment'])
				);
			}
		}
		return $out;
	}

}