MongoClient::__constructCreates a new database connection object
&reftitle.description;
publicMongoClient::__constructstringserver"mongodb://localhost:27017"arrayoptionsarray("connect" => &true;)
If no parameters are passed, this connects to "localhost:27017" (or whatever
was specified in php.ini for
mongo.default_host and
mongo.default_port).
server should have the form:
The connection string always starts with mongodb://, to
indicate it is a connection string in this form.
If username and password
are specified, the constructor will attempt to authenticate the connection
with the database before returning. Username and password are optional
and must be followed by an @, if specified.
At least one host must be given (port optional, always defaulting to 27017)
and as many hosts as desired may be connected to. Host names are
comma-separated and the constructor will return successfully if it connected
to at least one host. If it could not connect to any of the hosts, it will
throw a MongoConnectionException. Please see the
Replica Sets section for
information on how to connect to Replica Sets.
If you specified a username and password, you may specify a database to
authenticate with. If db is not specified, "admin" will
be used.
An optional query string may be used to specify extra options. The same
options are supported through the options array as
well, and are therefore redescribed there. See the examples below on
how to set those options.
One part of the options governs how the driver reads from secondary nodes
in a replica set environment. Extra information on how these read
preferences work is available as well through the read preferences documentation page.
&reftitle.parameters;
server
The server name.
options
An array of options for the connection. Currently available options
include:
"connect"
If the constructor should connect before returning. Default is
&true;. When set to &false; the driver will
automatically connection to the server whenever
it is necessary to do a query. Alternatively, you can run
MongoClient::connect manually.
This option is not supported through the connection string.
"connectTimeoutMS"
How long a connection can take to be opened before timing out.
"db"
The database to authenticate against can be specified here, instead of
including it in the host list. This overrides a database given in the
host list.
"fsync"
When fsync is set, all write operations on the
database will block until the database server has flushed its
database files to disk. This makes write operations a lot slower,
but it guarantees that the write operation has succeeded and
committed to disk. Please avoid using this
option and use the journal option instead,
perhaps in combination with the w option.
"journal"
When journal is set, all write operations on the
database will block until the database server has flushed the
journal to disk. This makes the write operations marginally slower,
but it guarantees that the write operation has succeeded and the
operation can be recovered in case of total system failure.
"password"
The password can be specified here, instead of including it in the
host list. This is especially useful if a password has a "@" in it.
This overrides a password set in the host list.
"readPreference"
Specifies the read preference type. Read preferences provide you
with control from which secondaries data can be read from.
Allowed values are: MongoClient::RP_PRIMARY,
MongoClient::RP_PRIMARY_PREFERRED,
MongoClient::RP_SECONDARY,
MongoClient::RP_SECONDARY_PREFERRED and
MongoClient::RP_NEAREST.
See the documentation on read
preferences for more information.
"readPreferenceTags"
Specifies the read preference tags as an array of strings. Tags can be
used in combination with the readPreference option
to further control which secondaries data might be read from.
See the documentation on read
preferences for more information.
"replicaSet"
The name of the replica set to connect to. If this is given, the
primary will be automatically be determined. This means that the
driver may end up connecting to a server that was not even listed.
See the replica set example below for details.
"socketTimeoutMS"
How long a send or receive on a socket can take before timing out.
This is a client side timeout. If an insert hits
the "socketTimeoutMS" value there is no way to
know if the server actually received the write or not.
"username"
The username can be specified here, instead of including it in the
host list. This is especially useful if a username has a ":" in it.
This overrides a username set in the host list.
"w"
The w option specifies the
Write Concern for the driver,
which determines how long the driver blocks when writing. The
default value is 1.
This option is applicable when connecting to both single servers and
replica sets. A positive value controls how many
nodes must acknowledge the write instruction before the driver
continues. A value of 1 would require the single
server or primary (in a replica set) to acknowledge the write
operation. A value of 3 would cause the driver to
block until the write has been applied to the primary as well as two
secondary servers (in a replica set).
A string value is used to control which tag sets are taken into
account for write concerns. "majority" is special
and ensures that the write operation has been applied to the majority
(more than 50%) of the participating nodes.
"wTimeoutMS"
This option is used in combination with the "w"
option. It controls how many milliseconds the server waits for the
write concern to be satisfied. If it takes longer then the server
signals to the driver that it took too long and the driver will throw
a MongoCursorException exception.
The following options are deprecated and should no longer be used:
"timeout"
Deprecated alias for "connectTimeoutMS".
"wTimeout"
Deprecated alias for "wTimeoutMS".
&reftitle.returnvalues;
Returns a new database connection object.
&reftitle.errors;
Throws MongoConnectionException if it tries and fails
to connect to the database for all hostnames given. It will also throw a
MongoConnnectionException if an invalid username or
password is given. See MongoConnectionException
documentation for common exceptions and their causes.
&reftitle.examples;
MongoClient::__construct replica set example
This example shows how to connect the driver to a replica set. It assumes
that there is a set of three servers: sf1.example.com, sf2.example.com, and
ny1.example.com. The primary could be any one of these servers.
"myReplSet"));
?>
]]>
If the current primary fails, the driver will figure out which secondary
server became the new primary and automatically start using that connection.
Automatic failover will not work correctly if replicaSet
is not specified.
At least one seed in the seed list must be up for the driver to connect to
the replica set.
If you include seeds from two separate replica sets, behavior is undefined.
See the
core documentation on
replica sets for more information.
Connecting to a domain socket
In version 1.0.9+, you can use a UNIX domain socket to connect to an
instance of MongoDB running locally. This should be slightly faster than
using a network connection.
In version 1.5.0, the MongoDB server automatically opens a socket at
/tmp/mongodb-<port>.sock. You can connect to this by specifying the
path in your connection string:
]]>
You can combine this with any other connections you'd like:
]]>
MongoClient::__construct authentication example
A user must exist in the admin database before attempting to use
authentication. You can create one with the Mongo shell by running:
use admin
switched to db admin
> db.addUser("testUser", "testPass");
{
"_id" : ObjectId("4b21272fd9ab21611d19095c"),
"user" : "testUser",
"pwd" : "03b9b27e0abf1865e2f6fcbd9845dd59"
}
>
]]>
After creating a user with, in this case, username "testUser" and password
"testPass", you can create an authenticated connection:
]]>
MongoClient::__construct read preference example
'rs'));
]]>
See the read preferences
section of this manual for further information.
MongoClient::__construct options example
Options can be passed both through the query string in the connection
string, or as an array passed as second argument to the constructor.
Here we set the journal option to true and readPreference to secondary
preferred as default for all write operations:
]]>
And now we do the same, but as an options array:
true,
'readPreference' => 'secondary',
);
$m = new MongoClient("mongodb://localhost/", $options);
?>
]]>
MongoClient::__construct read preference example
'rs'));
]]>
See the read preferences
section of this manual for further information.
&reftitle.changelog;
&Version;&Description;1.4.0
Added the "wTimeoutMS" option has replacement
for "wTimeout".
1.3.4
Added the "connectTimeoutMS" and
"socketTimeoutMS" options.
1.3.0
Added the "readPreference",
"readPreferenceTags", "w" and
"wTimeout" options.
1.2.0
Added the "username" and
"password" options.
Removed the "persist" option, as all connections are
now persistent. It can still be used, but it doesn't affect anything.
"persist"
If the connection should be persistent. If set, the connection will
be persistent. The string representation of the value is used as an
ID for the connection, so two instances of
MongoClient that are initialized with
array("persist" => "foobar") will share the same
database connection, whereas an instance initialized with
array("persist" => "barbaz") will use a different
database connection.
The "replicaSet" option now takes a string, not a
boolean.
1.0.9Added the "replicaSet" option.1.0.2
Changed constructor to take an array of options. Pre-1.0.2, the
constructor took the following parameters:
server
The server name.
connect
Optional boolean parameter specifying if the constructor should
connect to the database before returning. Defaults to &true;.
persistent
If the connection should be persistent.
paired
If the connection should be paired.