wikimedia/mediawiki-core

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includes/libs/rdbms/querybuilder/UpdateQueryBuilder.php

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<?php

namespace Wikimedia\Rdbms;

use InvalidArgumentException;
use UnexpectedValueException;

// Very long type annotations :(
// phpcs:disable Generic.Files.LineLength

/**
 * Build UPDATE queries with a fluent interface.
 *
 * Each query builder object must be used for a single database query only,
 * and not be reused afterwards. To run multiple similar queries, you can
 * create a query builder to set up most of your query, which you can use
 * as a "template" to clone. You can then modify the cloned object for
 * each individual query.
 *
 * @since 1.41
 * @stable to extend
 * @ingroup Database
 */
class UpdateQueryBuilder {
    /**
     * @var string The table name to be passed to IDatabase::update()
     */
    private $table = '';

    /**
     * @var array The set values to be passed to IDatabase::update()
     */
    private $set = [];

    /**
     * @var array The conditions to be passed to IDatabase::update()
     */
    private $conds = [];

    /**
     * @var string The caller (function name) to be passed to IDatabase::update()
     */
    private $caller = __CLASS__;

    /**
     * @var array The options to be passed to IDatabase::update()
     */
    protected $options = [];

    /** @var IDatabase */
    protected $db;

    /**
     * Only for use in subclasses. To create a UpdateQueryBuilder instance,
     * use `$db->newUpdateQueryBuilder()` instead.
     *
     * @param IDatabase $db
     */
    public function __construct( IDatabase $db ) {
        $this->db = $db;
    }

    /**
     * Change the IDatabase object the query builder is bound to. The specified
     * IDatabase will subsequently be used to execute the query.
     *
     * @param IDatabase $db
     * @return $this
     */
    public function connection( IDatabase $db ) {
        if ( $this->db->getType() !== $db->getType() ) {
            throw new InvalidArgumentException(
                __METHOD__ . ' cannot switch to a database of a different type.'
            );
        }
        $this->db = $db;
        return $this;
    }

    /**
     * Set the query parameters to the given values, appending to the values
     * which were already set. This can be used to interface with legacy code.
     * If a key is omitted, the previous value will be retained.
     *
     * The parameters must be formatted as required by Database::update.
     *
     * @param array $info Associative array of query info, with keys:
     *   - table: The table name to be passed to Database::update()
     *   - set: The set conditions
     *   - conds: The conditions
     *   - options: The query options
     *   - caller: The caller signature.
     *
     * @return $this
     */
    public function queryInfo( $info ) {
        if ( isset( $info['table'] ) ) {
            $this->table( $info['table'] );
        }
        if ( isset( $info['set'] ) ) {
            $this->set( $info['set'] );
        }
        if ( isset( $info['conds'] ) ) {
            $this->where( $info['conds'] );
        }
        if ( isset( $info['options'] ) ) {
            $this->options( (array)$info['options'] );
        }
        if ( isset( $info['caller'] ) ) {
            $this->caller( $info['caller'] );
        }
        return $this;
    }

    /**
     * Manually set the table name to be passed to IDatabase::update()
     *
     * @param string $table The unqualified name of a table
     * @param-taint $table exec_sql
     * @return $this
     */
    public function table( $table ) {
        $this->table = $table;
        return $this;
    }

    /**
     * Set table for the query. Alias for table().
     *
     * @param string $table The unqualified name of a table
     * @param-taint $table exec_sql
     * @return $this
     */
    public function update( string $table ) {
        return $this->table( $table );
    }

    /**
     * Manually set an option in the $options array to be passed to
     * IDatabase::update()
     *
     * @param string $name The option name
     * @param mixed $value The option value, or null for a boolean option
     * @return $this
     */
    public function option( $name, $value = null ) {
        if ( $value === null ) {
            $this->options[] = $name;
        } else {
            $this->options[$name] = $value;
        }
        return $this;
    }

    /**
     * Manually set multiple options in the $options array to be passed to
     * IDatabase::update().
     *
     * @param array $options
     * @return $this
     */
    public function options( array $options ) {
        $this->options = array_merge( $this->options, $options );
        return $this;
    }

    /**
     * Add conditions to the query. The supplied conditions will be appended
     * to the existing conditions, separated by AND.
     *
     * @param string|IExpression|array<string,?scalar|non-empty-array<int,?scalar>|RawSQLValue>|array<int,string|IExpression> $conds
     * @param-taint $conds exec_sql_numkey
     *
     * May be either a string containing a single condition, or an array of
     * conditions. If an array is given, the conditions constructed from each
     * element are combined with AND.
     *
     * Array elements may take one of two forms:
     *
     *   - Elements with a numeric key are interpreted as raw SQL fragments.
     *   - Elements with a string key are interpreted as equality conditions,
     *     where the key is the field name.
     *     - If the value of such an array element is a scalar (such as a
     *       string), it will be treated as data and thus quoted appropriately.
     *       If it is null, an IS NULL clause will be added.
     *     - If the value is an array, an IN (...) clause will be constructed
     *       from its non-null elements, and an IS NULL clause will be added
     *       if null is present, such that the field may match any of the
     *       elements in the array. The non-null elements will be quoted.
     *
     * Note that expressions are often DBMS-dependent in their syntax.
     * DBMS-independent wrappers are provided for constructing several types of
     * expression commonly used in condition queries. See:
     *    - IDatabase::buildLike()
     *    - IDatabase::conditional()
     *
     * Untrusted user input is safe in the values of string keys, however untrusted
     * input must not be used in the array key names or in the values of numeric keys.
     * Escaping of untrusted input used in values of numeric keys should be done via
     * IDatabase::addQuotes()
     *
     * @return $this
     */
    public function where( $conds ) {
        if ( is_array( $conds ) ) {
            foreach ( $conds as $key => $cond ) {
                if ( is_int( $key ) ) {
                    $this->conds[] = $cond;
                } elseif ( isset( $this->conds[$key] ) ) {
                    // @phan-suppress-previous-line PhanTypeMismatchDimFetch
                    // T288882
                    $this->conds[] = $this->db->makeList(
                        [ $key => $cond ], IDatabase::LIST_AND );
                } else {
                    $this->conds[$key] = $cond;
                }
            }
        } else {
            $this->conds[] = $conds;
        }
        return $this;
    }

    /**
     * Add conditions to the query. Alias for where().
     *
     * @param string|IExpression|array<string,?scalar|non-empty-array<int,?scalar>|RawSQLValue>|array<int,string|IExpression> $conds
     * @param-taint $conds exec_sql_numkey
     * @return $this
     */
    public function andWhere( $conds ) {
        return $this->where( $conds );
    }

    /**
     * Add conditions to the query. Alias for where().
     *
     * @param string|IExpression|array<string,?scalar|non-empty-array<int,?scalar>|RawSQLValue>|array<int,string|IExpression> $conds
     * @param-taint $conds exec_sql_numkey
     * @return $this
     */
    public function conds( $conds ) {
        return $this->where( $conds );
    }

    /**
     * Add SET part to the query. It takes an array containing arrays of column names map to
     * the set values.
     *
     * @param string|array<string,?scalar|RawSQLValue>|array<int,string> $set
     * @param-taint $set exec_sql_numkey
     *
     * Combination map/list where each string-keyed entry maps a column
     * to a literal assigned value and each integer-keyed value is a SQL expression in the
     * format of a column assignment within UPDATE...SET. The (column => value) entries are
     * convenient due to automatic value quoting and conversion of null to NULL. The SQL
     * assignment format is useful for updates like "column = column + X". All assignments
     * have no defined execution order, so they should not depend on each other. Do not
     * modify AUTOINCREMENT or UUID columns in assignments.
     *
     * Untrusted user input is safe in the values of string keys, however untrusted
     * input must not be used in the array key names or in the values of numeric keys.
     * Escaping of untrusted input used in values of numeric keys should be done via
     * IDatabase::addQuotes()
     *
     * @return $this
     */
    public function set( $set ) {
        if ( is_array( $set ) ) {
            foreach ( $set as $key => $value ) {
                if ( is_int( $key ) ) {
                    $this->set[] = $value;
                } else {
                    $this->set[$key] = $value;
                }
            }
        } else {
            $this->set[] = $set;
        }
        return $this;
    }

    /**
     * Add set values to the query. Alias for set().
     *
     * @param string|array<string,?scalar|RawSQLValue>|array<int,string> $set
     * @param-taint $set exec_sql_numkey
     * @return $this
     */
    public function andSet( $set ) {
        return $this->set( $set );
    }

    /**
     * Enable the IGNORE option.
     *
     * Skip update of rows that would cause unique key conflicts.
     * IDatabase::affectedRows() can be used to determine how many rows were updated.
     *
     * @return $this
     */
    public function ignore() {
        $this->options[] = 'IGNORE';
        return $this;
    }

    /**
     * Set the method name to be included in an SQL comment.
     *
     * @param string $fname
     * @param-taint $fname exec_sql
     * @return $this
     */
    public function caller( $fname ) {
        $this->caller = $fname;
        return $this;
    }

    /**
     * Run the constructed UPDATE query.
     */
    public function execute(): void {
        if ( !$this->conds ) {
            throw new UnexpectedValueException(
                __METHOD__ . ' expects at least one condition to be set' );
        }
        if ( !$this->set ) {
            throw new UnexpectedValueException(
                __METHOD__ . ' can\t have empty $set value' );
        }
        if ( $this->table === '' ) {
            throw new UnexpectedValueException(
                __METHOD__ . ' expects table not to be empty' );
        }
        $this->db->update( $this->table, $this->set, $this->conds, $this->caller, $this->options );
    }

    /**
     * Get an associative array describing the query in terms of its raw parameters to
     * Database::update(). This can be used to interface with legacy code.
     *
     * @return array The query info array, with keys:
     *   - table: The table name
     *   - set: The set array
     *   - conds: The conditions
     *   - options: The query options
     *   - caller: The caller signature
     */
    public function getQueryInfo() {
        $info = [
            'table' => $this->table,
            'set' => $this->set,
            'conds' => $this->conds,
            'options' => $this->options,
        ];
        if ( $this->caller !== __CLASS__ ) {
            $info['caller'] = $this->caller;
        }
        return $info;
    }
}