PHP: MongoDB\Driver\Manager::executeCommand

Description

final public MongoDB\Driver\Manager::executeCommand(string $db, MongoDB\Driver\Command $command, array|MongoDB\Driver\ReadPreference|null $options = null): MongoDB\Driver\Cursor

Selects a server according to the "readPreference" option and executes the command on that server.

This method applies no special logic to the command. The Default values for the "readPreference", "readConcern", and "writeConcern" options will be inferred from an active transaction (indicated by the "session" option). If there is no active transaction, a primary read preference will be used for server selection.

Default values will not be inferred from the connection URI. Users are therefore encouraged to use specific read and/or write command methods if possible.

Parameters

db (string)

The name of the database on which to execute the command.

command (MongoDB\Driver\Command)

The command to execute.

options

**options**
Option	Type	Description
readConcern	MongoDB\Driver\ReadConcern	A read concern to apply to the operation. This option is available in MongoDB 3.2+ and will result in an exception at execution time if specified for an older server version.
readPreference	MongoDB\Driver\ReadPreference	A read preference to use for selecting a server for the operation.
session	MongoDB\Driver\Session	A session to associate with the operation.
writeConcern	MongoDB\Driver\WriteConcern	A write concern to apply to the operation.

Warning

If you are using a "session" which has a transaction in progress, you cannot specify a "readConcern" or "writeConcern" option. This will result in an MongoDB\Driver\Exception\InvalidArgumentException being thrown. Instead, you should set these two options when you create the transaction with MongoDB\Driver\Session::startTransaction().

Return Values

Returns MongoDB\Driver\Cursor on success.

Errors/Exceptions

Throws MongoDB\Driver\Exception\InvalidArgumentException if the "session" option is used with an associated transaction in combination with a "readConcern" or "writeConcern" option.
Throws MongoDB\Driver\Exception\InvalidArgumentException if the "session" option is used in combination with an unacknowledged write concern.
Throws MongoDB\Driver\Exception\InvalidArgumentException on argument parsing errors.
Throws MongoDB\Driver\Exception\ConnectionException if connection to the server fails (for reasons other than authentication).
Throws MongoDB\Driver\Exception\AuthenticationException if authentication is needed and fails.
Throws MongoDB\Driver\Exception\RuntimeException on other errors (e.g. invalid command, issuing a write command to a secondary).

Changelog

Version	Description
PECL mongodb 1.4.4	MongoDB\Driver\Exception\InvalidArgumentException will be thrown if the `"session"` option is used in combination with an unacknowledged write concern.
PECL mongodb 1.4.0	The third parameter is now an `options` array. For backwards compatibility, this paramater will still accept a MongoDB\Driver\ReadPreference object.

Examples

Example #1 MongoDB\Driver\Manager::executeCommand() with a command returning a single result document

<?php

$manager = new MongoDB\Driver\Manager('mongodb://localhost:27017');
$command = new MongoDB\Driver\Command(['ping' => 1]);

try {
    $cursor = $manager->executeCommand('admin', $command);
} catch(MongoDB\Driver\Exception $e) {
    echo $e->getMessage(), "\n";
    exit;
}

/* The ping command returns a single result document, so we need to access the
 * first result in the cursor. */
$response = $cursor->toArray()[0];

var_dump($response);

?>

The above example will output:

array(1) {
  ["ok"]=>
  float(1)
}

Example #2 MongoDB\Driver\Manager::executeCommand() with a command returning a cursor

<?php

$manager = new MongoDB\Driver\Manager("mongodb://localhost:27017");

$bulk = new MongoDB\Driver\BulkWrite;
$bulk->insert(['x' => 1, 'y' => 'foo']);
$bulk->insert(['x' => 2, 'y' => 'bar']);
$bulk->insert(['x' => 3, 'y' => 'bar']);
$manager->executeBulkWrite('db.collection', $bulk);

$command = new MongoDB\Driver\Command([
    'aggregate' => 'collection',
    'pipeline' => [
        ['$group' => ['_id' => '$y', 'sum' => ['$sum' => '$x']]],
    ],
    'cursor' => new stdClass,
]);
$cursor = $manager->executeCommand('db', $command);

/* The aggregate command can optionally return its results in a cursor instead
 * of a single result document. In this case, we can iterate on the cursor
 * directly to access those results. */
foreach ($cursor as $document) {
    var_dump($document);
}

?>

The above example will output:

object(stdClass)#6 (2) {
  ["_id"]=>
  string(3) "bar"
  ["sum"]=>
  int(10)
}
object(stdClass)#7 (2) {
  ["_id"]=>
  string(3) "foo"
  ["sum"]=>
  int(2)
}

Example #3 Limiting execution time for a command

The execution time of a command may be limited by specifying a value for "maxTimeMS" in the MongoDB\Driver\Command document. Note that this time limit is enforced on the server side and does not take network latency into account. See » Terminate Running Operations in the MongoDB manual for more information.

<?php

$manager = new MongoDB\Driver\Manager('mongodb://localhost:27017');

$command = new MongoDB\Driver\Command([
    'count' => 'collection',
    'query' => ['x' => ['$gt' => 1]],
    'maxTimeMS' => 1000,
]);

$cursor = $manager->executeCommand('db', $command);

var_dump($cursor->toArray()[0]);

?>

If the command fails to complete after one second of execution time on the server, a MongoDB\Driver\Exception\ExecutionTimeoutException will be thrown.

Notes

Note: If a secondary readPreference is used, it is the caller's responsibility to ensure that the command can be executed on a secondary. No validation is done by the driver.

Note: This method does not default to using the read preference from the MongoDB Connection URI. Applications in need of that behavior should consider using MongoDB\Driver\Manager::executeReadCommand().

MongoDB\Driver\Manager::executeCommand