3 * This program is free software; you can redistribute it and/or modify
4 * it under the terms of the GNU General Public License as published by
5 * the Free Software Foundation; either version 2 of the License, or
6 * (at your option) any later version.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
13 * You should have received a copy of the GNU General Public License along
14 * with this program; if not, write to the Free Software Foundation, Inc.,
15 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
16 * http://www.gnu.org/copyleft/gpl.html
21 namespace Wikimedia\Rdbms
;
23 use InvalidArgumentException
;
26 * Class to handle database/prefix specification for IDatabase domains
28 class DatabaseDomain
{
29 /** @var string|null */
31 /** @var string|null */
36 /** @var string Cache of convertToString() */
37 private $equivalentString;
40 * @param string|null $database Database name
41 * @param string|null $schema Schema name
42 * @param string $prefix Table prefix
44 public function __construct( $database, $schema, $prefix ) {
45 if ( $database !== null && ( !is_string( $database ) ||
!strlen( $database ) ) ) {
46 throw new InvalidArgumentException( "Database must be null or a non-empty string." );
48 $this->database
= $database;
49 if ( $schema !== null && ( !is_string( $schema ) ||
!strlen( $schema ) ) ) {
50 throw new InvalidArgumentException( "Schema must be null or a non-empty string." );
52 $this->schema
= $schema;
53 if ( !is_string( $prefix ) ) {
54 throw new InvalidArgumentException( "Prefix must be a string." );
56 $this->prefix
= $prefix;
60 * @param DatabaseDomain|string $domain Result of DatabaseDomain::toString()
61 * @return DatabaseDomain
63 public static function newFromId( $domain ) {
64 if ( $domain instanceof self
) {
68 $parts = array_map( [ __CLASS__
, 'decode' ], explode( '-', $domain ) );
73 if ( count( $parts ) == 1 ) {
74 $database = $parts[0];
75 } elseif ( count( $parts ) == 2 ) {
76 list( $database, $prefix ) = $parts;
77 } elseif ( count( $parts ) == 3 ) {
78 list( $database, $schema, $prefix ) = $parts;
80 throw new InvalidArgumentException( "Domain '$domain' has too few or too many parts." );
83 if ( $database === '' ) {
87 if ( $schema === '' ) {
91 return new self( $database, $schema, $prefix );
95 * @return DatabaseDomain
97 public static function newUnspecified() {
98 return new self( null, null, '' );
102 * @param DatabaseDomain|string $other
103 * @return bool Whether the domain instances are the same by value
105 public function equals( $other ) {
106 if ( $other instanceof self
) {
108 $this->database
=== $other->database
&&
109 $this->schema
=== $other->schema
&&
110 $this->prefix
=== $other->prefix
114 return ( $this->getId() === $other );
118 * Check whether the domain $other meets the specifications of this domain
120 * If this instance has a null database specifier, then $other can have any database
121 * specified, including the null, and likewise if the schema specifier is null. This
122 * is not transitive like equals() since a domain that explicitly wants a certain
123 * database or schema cannot be satisfied by one of another (nor null). If the prefix
124 * is empty and the DB and schema are both null, then the entire domain is considered
125 * unspecified, and any prefix of $other is considered compatible.
127 * @param DatabaseDomain|string $other
131 public function isCompatible( $other ) {
132 if ( $this->isUnspecified() ) {
133 return true; // even the prefix doesn't matter
136 $other = ( $other instanceof self
) ?
$other : self
::newFromId( $other );
139 ( $this->database
=== $other->database ||
$this->database
=== null ) &&
140 ( $this->schema
=== $other->schema ||
$this->schema
=== null ) &&
141 $this->prefix
=== $other->prefix
149 public function isUnspecified() {
151 $this->database
=== null && $this->schema
=== null && $this->prefix
=== ''
156 * @return string|null Database name
158 public function getDatabase() {
159 return $this->database
;
163 * @return string|null Database schema
165 public function getSchema() {
166 return $this->schema
;
170 * @return string Table prefix
172 public function getTablePrefix() {
173 return $this->prefix
;
179 public function getId() {
180 if ( $this->equivalentString
=== null ) {
181 $this->equivalentString
= $this->convertToString();
184 return $this->equivalentString
;
190 private function convertToString() {
191 $parts = [ $this->database
];
192 if ( $this->schema
!== null ) {
193 $parts[] = $this->schema
;
195 if ( $this->prefix
!= '' ||
$this->schema
!== null ) {
196 // If there is a schema, then we need the prefix to disambiguate.
197 // For engines like Postgres that use schemas, this awkwardness is hopefully
198 // avoided since it is easy to have one DB per server (to avoid having many users)
199 // and use schema/prefix to have wiki farms. For example, a domain schemes could be
200 // wiki-<project>-<language>, e.g. "wiki-fitness-es"/"wiki-sports-fr"/"wiki-news-en".
201 $parts[] = $this->prefix
;
204 return implode( '-', array_map( [ __CLASS__
, 'encode' ], $parts ) );
207 private static function encode( $decoded ) {
210 $length = strlen( $decoded );
211 for ( $i = 0; $i < $length; ++
$i ) {
212 $char = $decoded[$i];
213 if ( $char === '-' ) {
215 } elseif ( $char === '?' ) {
225 private static function decode( $encoded ) {
228 $length = strlen( $encoded );
229 for ( $i = 0; $i < $length; ++
$i ) {
230 $char = $encoded[$i];
231 if ( $char === '?' ) {
232 $nextChar = $encoded[$i +
1] ??
null;
233 if ( $nextChar === 'h' ) {
236 } elseif ( $nextChar === '?' ) {
253 function __toString() {
254 return $this->getId();