Question

I want to use the mongodb _id attribute to guarantee uniqueness in a name.

mongo_cursor_init( cursor, &conn, &database );
bson_iterator iterator[1];

bson_find( iterator, mongo_cursor_bson( cursor ), "name" );
const char *filename = bson_iterator_string( iterator );

bson_find( iterator, mongo_cursor_bson( cursor ), "_id" );
const char *mongoid = bson_iterator_string(iterator);

char name[255];
strcpy(name,filename);
strcat(name,".");
strcat(name,mongoid);

However, the variable mongoid does not get populated correctly (at all…). I’m not sure how to find the datatype of _id. Has anyone done this before? Thanks!

edit: i think the answer is in here, but not sure…

Answer 1

Hope this helps somebody…

Mongo _id to string:

char mongoid[25];
bson_find( iterator, mongo_cursor_bson( cursor ), "_id" );
bson_oid_t *oid = bson_iterator_oid( iterator );
bson_oid_to_string(oid,mongoid);

string to Mongo _id:

bson_oid_t new_oid;
bson_oid_from_string(&new_oid,mongoid);