:man_page: mongoc_uri_t mongoc_uri_t ============ Synopsis -------- .. code-block:: c typedef struct _mongoc_uri_t mongoc_uri_t; Description ----------- ``mongoc_uri_t`` provides an abstraction on top of the MongoDB connection URI format. It provides standardized parsing as well as convenience methods for extracting useful information such as replica hosts or authorization information. See `Connection String URI Reference `_ on the MongoDB website for more information. Format ------ .. code-block:: none mongodb[+srv]:// <1> [username:password@] <2> host1 <3> [:port1] <4> [,host2[:port2],...[,hostN[:portN]]] <5> [/[database] <6> [?options]] <7> #. "mongodb" is the specifier of the MongoDB protocol. Use "mongodb+srv" with a single service name in place of "host1" to specify the initial list of servers with an SRV record. #. An optional username and password. #. The only required part of the uri. This specifies either a hostname, IPv4 address, IPv6 address enclosed in "[" and "]", or UNIX domain socket. #. An optional port number. Defaults to :27017. #. Extra optional hosts and ports. You would specify multiple hosts, for example, for connections to replica sets. #. The name of the database to authenticate if the connection string includes authentication credentials. If /database is not specified and the connection string includes credentials, defaults to the 'admin' database. #. Connection specific options. .. note:: Option names are case-insensitive. Do not repeat the same option (e.g. "mongodb://localhost/db?opt=value1&OPT=value2") since this may have unexpected results. The MongoDB C Driver exposes constants for each supported connection option. These constants make it easier to discover connection options, but their string values can be used as well. For example, the following calls are equal. .. code-block:: c uri = mongoc_uri_new ("mongodb://localhost/?" MONGOC_URI_APPNAME "=applicationName"); uri = mongoc_uri_new ("mongodb://localhost/?appname=applicationName"); uri = mongoc_uri_new ("mongodb://localhost/?appName=applicationName"); Replica Set Example ------------------- To describe a connection to a replica set named 'test' with the following mongod hosts: * ``db1.example.com`` on port ``27017`` * ``db2.example.com`` on port ``2500`` You would use a connection string that resembles the following. .. code-block:: none mongodb://db1.example.com,db2.example.com:2500/?replicaSet=test SRV Example ----------- If you have configured an `SRV record `_ with a name like "_mongodb._tcp.server.example.com" whose records are a list of one or more MongoDB server hostnames, use a connection string like this: .. code-block:: c uri = mongoc_uri_new ("mongodb+srv://server.example.com/?replicaSet=rs&appName=applicationName"); The driver prefixes the service name with "_mongodb._tcp.", then performs a DNS SRV query to resolve the service name to one or more hostnames. If this query succeeds, the driver performs a DNS TXT query on the service name (without the "_mongodb._tcp" prefix) for additional URI options configured as TXT records. On Unix, the MongoDB C Driver relies on libresolv to look up SRV and TXT records. If libresolv is unavailable, then using a "mongodb+srv" URI will cause an error. If your libresolv lacks ``res_nsearch`` then the driver will fall back to ``res_search``, which is not thread-safe. IPv4 and IPv6 ------------- .. include:: includes/ipv4-and-ipv6.txt Connection Options ------------------ ========================================== ================================= ================================= ============================================================================================================================================================================================================================================ Constant Key Default Description ========================================== ================================= ================================= ============================================================================================================================================================================================================================================ MONGOC_URI_RETRYREADS retryreads true If "true" and the server is a MongoDB 3.6+ standalone, replica set, or sharded cluster, the driver safely retries a read that failed due to a network error or replica set failover. MONGOC_URI_RETRYWRITES retrywrites true if driver built w/ TLS If "true" and the server is a MongoDB 3.6+ replica set or sharded cluster, the driver safely retries a write that failed due to a network error or replica set failover. Only inserts, updates of single documents, or deletes of single documents are retried. MONGOC_URI_APPNAME appname Empty (no appname) The client application name. This value is used by MongoDB when it logs connection information and profile information, such as slow queries. MONGOC_URI_TLS tls Empty (not set, same as false) {true|false}, indicating if TLS must be used. (See also :symbol:`mongoc_client_set_ssl_opts` and :symbol:`mongoc_client_pool_set_ssl_opts`.) MONGOC_URI_COMPRESSORS compressors Empty (no compressors) Comma separated list of compressors, if any, to use to compress the wire protocol messages. Snappy, zlib, and zstd are optional build time dependencies, and enable the "snappy", "zlib", and "zstd" values respectively. MONGOC_URI_CONNECTTIMEOUTMS connecttimeoutms 10,000 ms (10 seconds) This setting applies to new server connections. It is also used as the socket timeout for server discovery and monitoring operations. MONGOC_URI_SOCKETTIMEOUTMS sockettimeoutms 300,000 ms (5 minutes) The time in milliseconds to attempt to send or receive on a socket before the attempt times out. MONGOC_URI_REPLICASET replicaset Empty (no replicaset) The name of the Replica Set that the driver should connect to. MONGOC_URI_ZLIBCOMPRESSIONLEVEL zlibcompressionlevel -1 When the MONGOC_URI_COMPRESSORS includes "zlib" this options configures the zlib compression level, when the zlib compressor is used to compress client data. MONGOC_URI_LOADBALANCED loadbalanced false If true, this indicates the driver is connecting to a MongoDB cluster behind a load balancer. MONGOC_URI_SRVMAXHOSTS srvmaxhosts 0 If zero, the number of hosts in DNS results is unlimited. If greater than zero, the number of hosts in DNS results is limited to being less than or equal to the given value. ========================================== ================================= ================================= ============================================================================================================================================================================================================================================ Setting any of the \*timeoutMS options above to ``0`` will be interpreted as "use the default value". Authentication Options ---------------------- ========================================== ================================= ========================================================================================================================================================================================================================= Constant Key Description ========================================== ================================= ========================================================================================================================================================================================================================= MONGOC_URI_AUTHMECHANISM authmechanism Specifies the mechanism to use when authenticating as the provided user. See :doc:`Authentication ` for supported values. MONGOC_URI_AUTHMECHANISMPROPERTIES authmechanismproperties Certain authentication mechanisms have additional options that can be configured. These options should be provided as comma separated option_key:option_value pair and provided as authMechanismProperties. Specifying the same option_key multiple times has undefined behavior. MONGOC_URI_AUTHSOURCE authsource The authSource defines the database that should be used to authenticate to. It is unnecessary to provide this option the database name is the same as the database used in the URI. ========================================== ================================= ========================================================================================================================================================================================================================= Mechanism Properties ~~~~~~~~~~~~~~~~~~~~ ========================================== ================================= ========================================================================================================================================================================================================================= Constant Key Description ========================================== ================================= ========================================================================================================================================================================================================================= MONGOC_URI_CANONICALIZEHOSTNAME canonicalizehostname Use the canonical hostname of the service, rather than its configured alias, when authenticating with Cyrus-SASL Kerberos. MONGOC_URI_GSSAPISERVICENAME gssapiservicename Use alternative service name. The default is ``mongodb``. ========================================== ================================= ========================================================================================================================================================================================================================= .. _tls_options: TLS Options ----------- .. include:: includes/tls-options.txt See :doc:`configuring_tls` for details about these options and about building libmongoc with TLS support. Deprecated SSL Options ---------------------- The following options have been deprecated and may be removed from future releases of libmongoc. ========================================== ================================= =========================================== ================================= Constant Key Deprecated For Key ========================================== ================================= =========================================== ================================= MONGOC_URI_SSL ssl MONGOC_URI_TLS tls MONGOC_URI_SSLCLIENTCERTIFICATEKEYFILE sslclientcertificatekeyfile MONGOC_URI_TLSCERTIFICATEKEYFILE tlscertificatekeyfile MONGOC_URI_SSLCLIENTCERTIFICATEKEYPASSWORD sslclientcertificatekeypassword MONGOC_URI_TLSCERTIFICATEKEYFILEPASSWORD tlscertificatekeypassword MONGOC_URI_SSLCERTIFICATEAUTHORITYFILE sslcertificateauthorityfile MONGOC_URI_TLSCAFILE tlscafile MONGOC_URI_SSLALLOWINVALIDCERTIFICATES sslallowinvalidcertificates MONGOC_URI_TLSALLOWINVALIDCERTIFICATES tlsallowinvalidcertificates MONGOC_URI_SSLALLOWINVALIDHOSTNAMES sslallowinvalidhostnames MONGOC_URI_TLSALLOWINVALIDHOSTNAMES tlsallowinvalidhostnames ========================================== ================================= =========================================== ================================= .. _sdam_uri_options: Server Discovery, Monitoring, and Selection Options --------------------------------------------------- Clients in a :symbol:`mongoc_client_pool_t` share a topology scanner that runs on a background thread. The thread wakes every ``heartbeatFrequencyMS`` (default 10 seconds) to scan all MongoDB servers in parallel. Whenever an application operation requires a server that is not known--for example, if there is no known primary and your application attempts an insert--the thread rescans all servers every half-second. In this situation the pooled client waits up to ``serverSelectionTimeoutMS`` (default 30 seconds) for the thread to find a server suitable for the operation, then returns an error with domain ``MONGOC_ERROR_SERVER_SELECTION``. Technically, the total time an operation may wait while a pooled client scans the topology is controlled both by ``serverSelectionTimeoutMS`` and ``connectTimeoutMS``. The longest wait occurs if the last scan begins just at the end of the selection timeout, and a slow or down server requires the full connection timeout before the client gives up. A non-pooled client is single-threaded. Every ``heartbeatFrequencyMS``, it blocks the next application operation while it does a parallel scan. This scan takes as long as needed to check the slowest server: roughly ``connectTimeoutMS``. Therefore the default ``heartbeatFrequencyMS`` for single-threaded clients is greater than for pooled clients: 60 seconds. By default, single-threaded (non-pooled) clients scan only once when an operation requires a server that is not known. If you attempt an insert and there is no known primary, the client checks all servers once trying to find it, then succeeds or returns an error with domain ``MONGOC_ERROR_SERVER_SELECTION``. But if you set ``serverSelectionTryOnce`` to "false", the single-threaded client loops, checking all servers every half-second, until ``serverSelectionTimeoutMS``. The total time an operation may wait for a single-threaded client to scan the topology is determined by ``connectTimeoutMS`` in the try-once case, or ``serverSelectionTimeoutMS`` and ``connectTimeoutMS`` if ``serverSelectionTryOnce`` is set "false". ========================================== ================================= ========================================================================================================================================================================================================================= Constant Key Description ========================================== ================================= ========================================================================================================================================================================================================================= MONGOC_URI_HEARTBEATFREQUENCYMS heartbeatfrequencyms The interval between server monitoring checks. Defaults to 10,000ms (10 seconds) in pooled (multi-threaded) mode, 60,000ms (60 seconds) in non-pooled mode (single-threaded). MONGOC_URI_SERVERSELECTIONTIMEOUTMS serverselectiontimeoutms A timeout in milliseconds to block for server selection before throwing an exception. The default is 30,0000ms (30 seconds). MONGOC_URI_SERVERSELECTIONTRYONCE serverselectiontryonce If "true", the driver scans the topology exactly once after server selection fails, then either selects a server or returns an error. If it is false, then the driver repeatedly searches for a suitable server for up to ``serverSelectionTimeoutMS`` milliseconds (pausing a half second between attempts). The default for ``serverSelectionTryOnce`` is "false" for pooled clients, otherwise "true". Pooled clients ignore serverSelectionTryOnce; they signal the thread to rescan the topology every half-second until serverSelectionTimeoutMS expires. MONGOC_URI_SOCKETCHECKINTERVALMS socketcheckintervalms Only applies to single threaded clients. If a socket has not been used within this time, its connection is checked with a quick "hello" call before it is used again. Defaults to 5,000ms (5 seconds). MONGOC_URI_DIRECTCONNECTION directconnection If "true", the driver connects to a single server directly and will not monitor additional servers. If "false", the driver connects based on the presence and value of the ``replicaSet`` option. ========================================== ================================= ========================================================================================================================================================================================================================= Setting any of the \*TimeoutMS options above to ``0`` will be interpreted as "use the default value". .. _connection_pool_options: Connection Pool Options ----------------------- These options govern the behavior of a :symbol:`mongoc_client_pool_t`. They are ignored by a non-pooled :symbol:`mongoc_client_t`. ========================================== ================================= ========================================================================================================================================================================================================================= Constant Key Description ========================================== ================================= ========================================================================================================================================================================================================================= MONGOC_URI_MAXPOOLSIZE maxpoolsize The maximum number of clients created by a :symbol:`mongoc_client_pool_t` total (both in the pool and checked out). The default value is 100. Once it is reached, :symbol:`mongoc_client_pool_pop` blocks until another thread pushes a client. MONGOC_URI_MINPOOLSIZE minpoolsize Deprecated. This option's behavior does not match its name, and its actual behavior will likely hurt performance. MONGOC_URI_MAXIDLETIMEMS maxidletimems Not implemented. MONGOC_URI_WAITQUEUEMULTIPLE waitqueuemultiple Not implemented. MONGOC_URI_WAITQUEUETIMEOUTMS waitqueuetimeoutms The maximum time to wait for a client to become available from the pool. ========================================== ================================= ========================================================================================================================================================================================================================= .. _mongoc_uri_t_write_concern_options: Write Concern Options --------------------- ========================================== ================================= ======================================================================================================================================================================= Constant Key Description ========================================== ================================= ======================================================================================================================================================================= MONGOC_URI_W w Determines the write concern (guarantee). Valid values: * 0 = The driver will not acknowledge write operations but will pass or handle any network and socket errors that it receives to the client. If you disable write concern but enable the getLastError command’s w option, w overrides the w option. * 1 = Provides basic acknowledgement of write operations. By specifying 1, you require that a standalone mongod instance, or the primary for replica sets, acknowledge all write operations. For drivers released after the default write concern change, this is the default write concern setting. * majority = For replica sets, if you specify the special majority value to w option, write operations will only return successfully after a majority of the configured replica set members have acknowledged the write operation. * n = For replica sets, if you specify a number n greater than 1, operations with this write concern return only after n members of the set have acknowledged the write. If you set n to a number that is greater than the number of available set members or members that hold data, MongoDB will wait, potentially indefinitely, for these members to become available. * tags = For replica sets, you can specify a tag set to require that all members of the set that have these tags configured return confirmation of the write operation. MONGOC_URI_WTIMEOUTMS wtimeoutms The time in milliseconds to wait for replication to succeed, as specified in the w option, before timing out. When wtimeoutMS is 0, write operations will never time out. MONGOC_URI_JOURNAL journal Controls whether write operations will wait until the mongod acknowledges the write operations and commits the data to the on disk journal. * true = Enables journal commit acknowledgement write concern. Equivalent to specifying the getLastError command with the j option enabled. * false = Does not require that mongod commit write operations to the journal before acknowledging the write operation. This is the default option for the journal parameter. ========================================== ================================= ======================================================================================================================================================================= .. _mongoc_uri_t_read_concern_options: Read Concern Options -------------------- ========================================== ================================= ========================================================================================================================================================================================================================= Constant Key Description ========================================== ================================= ========================================================================================================================================================================================================================= MONGOC_URI_READCONCERNLEVEL readconcernlevel The level of isolation for read operations. If the level is left unspecified, the server default will be used. See `readConcern in the MongoDB Manual `_ for details. ========================================== ================================= ========================================================================================================================================================================================================================= .. _mongoc_uri_t_read_prefs_options: Read Preference Options ----------------------- When connected to a replica set, the driver chooses which member to query using the read preference: #. Choose members whose type matches "readPreference". #. From these, if there are any tags sets configured, choose members matching the first tag set. If there are none, fall back to the next tag set and so on, until some members are chosen or the tag sets are exhausted. #. From the chosen servers, distribute queries randomly among the server with the fastest round-trip times. These include the server with the fastest time and any whose round-trip time is no more than "localThresholdMS" slower. ========================================== ================================= ======================================================================================================================================================================= Constant Key Description ========================================== ================================= ======================================================================================================================================================================= MONGOC_URI_READPREFERENCE readpreference Specifies the replica set read preference for this connection. This setting overrides any secondaryOk value. The read preference values are the following: * primary (default) * primaryPreferred * secondary * secondaryPreferred * nearest MONGOC_URI_READPREFERENCETAGS readpreferencetags A representation of a tag set. See also :ref:`mongoc-read-prefs-tag-sets`. MONGOC_URI_LOCALTHRESHOLDMS localthresholdms How far to distribute queries, beyond the server with the fastest round-trip time. By default, only servers within 15ms of the fastest round-trip time receive queries. MONGOC_URI_MAXSTALENESSSECONDS maxstalenessseconds The maximum replication lag, in wall clock time, that a secondary can suffer and still be eligible. The smallest allowed value for maxStalenessSeconds is 90 seconds. ========================================== ================================= ======================================================================================================================================================================= .. note:: When connecting to more than one mongos, libmongoc's localThresholdMS applies only to the selection of mongos servers. The threshold for selecting among replica set members in shards is controlled by the `mongos's localThreshold command line option `_. Legacy Options -------------- For historical reasons, the following options are available. They should however not be used. ========================================== ================================= ======================================================================================================================================================================= Constant Key Description ========================================== ================================= ======================================================================================================================================================================= MONGOC_URI_SAFE safe {true|false} Same as w={1|0} ========================================== ================================= ======================================================================================================================================================================= .. only:: html Functions --------- .. toctree:: :titlesonly: :maxdepth: 1 mongoc_uri_copy mongoc_uri_destroy mongoc_uri_get_auth_mechanism mongoc_uri_get_auth_source mongoc_uri_get_compressors mongoc_uri_get_database mongoc_uri_get_hosts mongoc_uri_get_mechanism_properties mongoc_uri_get_option_as_bool mongoc_uri_get_option_as_int32 mongoc_uri_get_option_as_int64 mongoc_uri_get_option_as_utf8 mongoc_uri_get_options mongoc_uri_get_password mongoc_uri_get_read_concern mongoc_uri_get_read_prefs mongoc_uri_get_read_prefs_t mongoc_uri_get_replica_set mongoc_uri_get_service mongoc_uri_get_ssl mongoc_uri_get_string mongoc_uri_get_srv_hostname mongoc_uri_get_srv_service_name mongoc_uri_get_tls mongoc_uri_get_username mongoc_uri_get_write_concern mongoc_uri_has_option mongoc_uri_new mongoc_uri_new_for_host_port mongoc_uri_new_with_error mongoc_uri_option_is_bool mongoc_uri_option_is_int32 mongoc_uri_option_is_int64 mongoc_uri_option_is_utf8 mongoc_uri_set_auth_mechanism mongoc_uri_set_auth_source mongoc_uri_set_compressors mongoc_uri_set_database mongoc_uri_set_mechanism_properties mongoc_uri_set_option_as_bool mongoc_uri_set_option_as_int32 mongoc_uri_set_option_as_int64 mongoc_uri_set_option_as_utf8 mongoc_uri_set_password mongoc_uri_set_read_concern mongoc_uri_set_read_prefs_t mongoc_uri_set_username mongoc_uri_set_write_concern mongoc_uri_unescape