mongoc_client_get_handshake_description - Man Page

mongoc_client_get_handshake_description()

Synopsis

mongoc_server_description_t *
mongoc_client_get_handshake_description (mongoc_client_t *client,
                                         uint32_t server_id,
                                         bson_t *opts,
                                         bson_error_t *error)
   BSON_GNUC_WARN_UNUSED_RESULT;

Returns a description constructed from the initial handshake response to a server.

Description

mongoc_client_get_handshake_description is distinct from mongoc_client_get_server_description. mongoc_client_get_server_description returns a server description constructed from monitoring, which may differ from the server description constructed from the connection handshake.

mongoc_client_get_handshake_description will attempt to establish a connection to the server if a connection was not already established. It will perform the MongoDB handshake and authentication if required.

Use this function only for building a language driver that wraps the C Driver. When writing applications in C, higher-level functions automatically select a suitable server.

Single-threaded client behavior

Single-threaded clients only have one active connection to each server. The one connection is used for both monitoring and application operations. However, the server description returned by mongoc_client_get_handshake_description may still differ from the server description returned by mongoc_client_get_server_description. Notably, if connected to a load balanced cluster, the server description returned by mongoc_client_get_server_description will describe the load balancer server (mongoc_server_description_type will return "LoadBalancer"). And the server description returned by mongoc_client_get_handshake_description will describe the backing server.

Parameters

Returns

A mongoc_server_description_t that must be freed with mongoc_server_description_destroy. If a connection has not been successfully established to a server, returns NULL and error is filled out.

See Also

Author

MongoDB, Inc

Info

Jan 06, 2022 1.20.1 libmongoc