mongodb.c File Reference

MongoDB database driver for csilk. More...

#include <mongoc/mongoc.h>
#include <stdlib.h>
#include <string.h>
#include "csilk/csilk.h"
#include "csilk/drivers/db.h"

Include dependency graph for mongodb.c:

Data Structures
struct	mongodb_conn_t
	Per-connection data for the MongoDB driver. More...

Functions
static void	mongodb_ensure_init (void)
	Initialize libmongoc once.
static int	mongodb_connect (csilk_db_pool_t *pool, const char *dsn)
	Open a connection to MongoDB using a URI.
static int	mongodb_disconnect (csilk_db_pool_t *pool)
	Close the MongoDB connection and free associated data.
static void	mongodb_free_result (csilk_db_result_t *result)
	Free a MongoDB query result set.
static char *	bson_val_to_str (const bson_iter_t *iter)
	Helper: Convert a BSON value to a string representation.
static int	mongodb_query (csilk_db_pool_t *pool, const char *sql, csilk_db_result_t *result)
	Execute a MongoDB query and return results as tabular rows.
static int	mongodb_exec (csilk_db_pool_t *pool, const char *sql)
	Execute a non-query command (INSERT, UPDATE, DELETE).
static int	mongodb_transaction_begin (csilk_db_pool_t *pool)
static int	mongodb_transaction_commit (csilk_db_pool_t *pool)
static int	mongodb_transaction_rollback (csilk_db_pool_t *pool)
void	csilk_db_mongodb_init (void)

Variables
csilk_db_driver_t	csilk_db_mongodb_driver

Detailed Description

MongoDB database driver for csilk.

Implements the csilk_db_driver_t vtable using the native libmongoc C API. Key design points:

• The DSN is a standard MongoDB URI (e.g., "mongodb://localhost:27017/testdb").
• SELECT queries (via .query) can be: a) A simple collection name (returns all documents). b) A JSON command string (e.g., {"find": "users", "filter": {...}}).
• BSON documents are flattened to tabular rows; the first document defines the column names for the result set.

Copyright

MIT License

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Data Structure Documentation

mongodb_conn_t

struct mongodb_conn_t

Per-connection data for the MongoDB driver.

Data Fields
mongoc_client_t *	client
char *	db_name

Function Documentation

bson_val_to_str()

static char * bson_val_to_str ( const bson_iter_t *  iter )

static

Helper: Convert a BSON value to a string representation.

csilk_db_mongodb_init()

void csilk_db_mongodb_init

(

void

)

mongodb_connect()

static int mongodb_connect ( csilk_db_pool_t *  pool, const char *  dsn  )

static

Open a connection to MongoDB using a URI.

Extracts the database name from the URI if provided, otherwise defaults to "test".

Parameters

pool	The database pool to initialize.
dsn	MongoDB URI string.

Returns

0 on success, -1 if URI is invalid or connection fails.

mongodb_disconnect()

static int mongodb_disconnect ( csilk_db_pool_t *  pool )

static

Close the MongoDB connection and free associated data.

mongodb_ensure_init()

static void mongodb_ensure_init ( void  )

static

Initialize libmongoc once.

mongodb_exec()

static int mongodb_exec ( csilk_db_pool_t *  pool, const char *  sql  )

static

Execute a non-query command (INSERT, UPDATE, DELETE).

The 'sql' parameter should be a JSON command.

mongodb_free_result()

static void mongodb_free_result ( csilk_db_result_t *  result )

static

Free a MongoDB query result set.

mongodb_query()

static int mongodb_query ( csilk_db_pool_t *  pool, const char *  sql, csilk_db_result_t *  result  )

static

Execute a MongoDB query and return results as tabular rows.

Support:

1. Simple collection name: "users" -> find all.
2. JSON command: {"find": "users", "filter": {...}} -> execute command.

mongodb_transaction_begin()

static int mongodb_transaction_begin ( csilk_db_pool_t *  pool )

static

mongodb_transaction_commit()

static int mongodb_transaction_commit ( csilk_db_pool_t *  pool )

static

mongodb_transaction_rollback()

static int mongodb_transaction_rollback ( csilk_db_pool_t *  pool )

static

Variable Documentation

csilk_db_mongodb_driver

csilk_db_driver_t csilk_db_mongodb_driver

Initial value:

= {
    .name = "mongodb",
    .connect = mongodb_connect,
    .disconnect = mongodb_disconnect,
    .query = mongodb_query,
    .exec = mongodb_exec,
    .transaction_begin = mongodb_transaction_begin,
    .transaction_commit = mongodb_transaction_commit,
    .transaction_rollback = mongodb_transaction_rollback,
    .free_result = mongodb_free_result,
}