NAME

       mongoc_client_t - MongoDB Connection Abstraction

SYNOPSIS

       typedef struct _mongoc_client_t mongoc_client_t;

       typedef mongoc_stream_t *
       (*mongoc_stream_initiator_t) (const mongoc_uri_t       *uri,
                                     const mongoc_host_list_t *host,
                                     void                     *user_data,
                                     bson_error_t             *error);

       mongoc_client_t  is an opaque type that provides access to a MongoDB node, replica‐set, or
       sharded‐cluster. It maintains management of underlying sockets and routing  to  individual
       nodes based on mongoc_read_prefs_t or mongoc_write_concern_t \&.

STREAMS

       The  underlying transport for a given client can be customized, wrapped or replaced by any
       implementation that fulfills mongoc_stream_t \&.  A  custom  transport  can  be  set  with
       mongoc_client_set_stream_initiator(3) \&.

THREAD SAFETY

       mongoc_client_t is NOT thread‐safe and should only be used from one thread at a time. When
       used in  multi‐threaded  scenarios,  it  is  recommended  that  you  use  the  thread‐safe
       mongoc_client_pool_t to retrieve a mongoc_client_t for your thread.

LIFECYCLE

       It  is  an error to call mongoc_client_destroy on a client that has operations pending. It
       is required that you release mongoc_collection_t and mongoc_database_t  structures  before
       calling mongoc_client_destroy \&.

EXAMPLE

       /* gcc example.c ‐o example $(pkg‐config ‐‐cflags ‐‐libs libmongoc‐1.0) */

       /* ./example‐client [CONNECTION_STRING [COLLECTION_NAME]] */

       #include <mongoc.h>
       #include <stdio.h>
       #include <stdlib.h>

       int
       main (int   argc,
             char *argv[])
       {
          mongoc_client_t *client;
          mongoc_collection_t *collection;
          mongoc_cursor_t *cursor;
          bson_error_t error;
          const bson_t *doc;
          const char *uristr = "mongodb://127.0.0.1/";
          const char *collection_name = "test";
          bson_t query;
          char *str;

          mongoc_init ();

          if (argc > 1) {
             uristr = argv [1];
          }

          if (argc > 2) {
             collection_name = argv [2];
          }

          client = mongoc_client_new (uristr);

          if (!client) {
             fprintf (stderr, "Failed to parse URI.\n");
             return EXIT_FAILURE;
          }

          bson_init (&query);

       #if 0
          bson_append_utf8 (&query, "hello", ‐1, "world", ‐1);
       #endif

          collection = mongoc_client_get_collection (client, "test", collection_name);
          cursor = mongoc_collection_find (collection,
                                           MONGOC_QUERY_NONE,
                                           0,
                                           0,
                                           0,
                                           &query,
                                           NULL,  /* Fields, NULL for all. */
                                           NULL); /* Read Prefs, NULL for default */

          while (mongoc_cursor_next (cursor, &doc)) {
             str = bson_as_json (doc, NULL);
             fprintf (stdout, "%s\n", str);
             bson_free (str);
          }

          if (mongoc_cursor_error (cursor, &error)) {
             fprintf (stderr, "Cursor Failure: %s\n", error.message);
             return EXIT_FAILURE;
          }

          bson_destroy (&query);
          mongoc_cursor_destroy (cursor);
          mongoc_collection_destroy (collection);
          mongoc_client_destroy (client);

          mongoc_cleanup ();

          return EXIT_SUCCESS;
       }

COLOPHON

       This    page   is   part   of   MongoDB   C   Driver.    Please   report   any   bugs   at
       https://jira.mongodb.org/browse/CDRIVER.