Am 22.01.2014 16:37, schrieb Kai-Heng Feng:

On Wed, 22 Jan 2014 13:05:40 +0100, Sönke Ludwig wrote:

Am 22.01.2014 04:51, schrieb Kai-Heng Feng:

I want to organize my REST APIs in different modules,
I am wondering if I use connectMongoDB in these classes (or even in functions)
are some kind of bad practice?

Or should I use connectMongoDB once,
then pass the MongoClient through class constructor?

Thanks!

Passing a single MongoClient instance - or, maybe even better, the
derived MongoDatabase or MongoCollection instances - to each class
is the best approach. Each MongoClient contains its own connection
pool to the DB server, so creating multiple clients will also result in
multiple connections to the DB (even though this will usually not be a
severe issue).

Now I passes MongoClient through different class's constructor, and
it works pretty well.

Since MongoClient is a class, I should simply pass it without ref
qualifier because it's already ref-counted, right?

Exactly, same for MongoDatabase and MongoCollection. Even if those
are structs, they basically only contain a reference to the
MongoClient, so copying them is a cheap operation.

BTW, strictly speaking, MogoClient is not reference counted, but
managed by the garbage collector, which makes it even cheaper to
copy/pass around.

Thanks for your help again.