C#•2y ago

System.AggregateException

'Some services are not able to be constructed (Error while validating the service descriptor 'ServiceType: BaseApi.Repository.UserRepository Lifetime: Singleton ImplementationType: BaseApi.Repository.UserRepository': Unable to resolve service for type 'MongoDB.Driver.IMongoDatabase' while attempting to activate 'BaseApi.Repository.UserRepository'.)'

'Some services are not able to be constructed (Error while validating the service descriptor 'ServiceType: BaseApi.Repository.UserRepository Lifetime: Singleton ImplementationType: BaseApi.Repository.UserRepository': Unable to resolve service for type 'MongoDB.Driver.IMongoDatabase' while attempting to activate 'BaseApi.Repository.UserRepository'.)'

I'm trying to build an API with using MongoDB. Sorry for so much screenshots I just wanted to show you all my work and understand what to change and what are my mistakes. I'm kinda new at .net core

Pobiega•3/13/24, 10:27 AM

Your class request a from the service provider

Pobiega•3/13/24, 10:27 AM

but you have never registered any type

only you knowOP•3/13/24, 10:29 AM

so what should I do

Pobiega•3/13/24, 10:30 AM

you must register IMongoDatabase somehow. Where is that interface from?

only you knowOP•3/13/24, 10:31 AM

it has his own interface

only you knowOP•3/13/24, 10:31 AM

comes with mongodb.driver

only you knowOP•3/13/24, 10:31 AM

Pobiega•3/13/24, 10:32 AM

okay, and how does the documentation suggest you get an instance of this?

Pobiega•3/13/24, 10:33 AM

ah I see, thats whats happening in your class

only you knowOP•3/13/24, 10:34 AM

what about this it might be wrong

Pobiega•3/13/24, 10:34 AM

that is the class you should be requesting, not , and to do that you must register

only you knowOP•3/13/24, 10:34 AM

then I should change here right

Pobiega•3/13/24, 10:35 AM

Do you understand how dependency injection works?

Pobiega•3/13/24, 10:35 AM

yes

Pobiega•3/13/24, 10:35 AM

like, that code makes no sense at all tbh

Pobiega•3/13/24, 10:35 AM

you're injecting a database connection, but also creating a new one?

Pobiega•3/13/24, 10:35 AM

and the one you created is then ignored

PPobiega like, that code makes no sense at all tbh

only you knowOP•3/13/24, 10:36 AM

that code meaning constructor or whole repo class?

Pobiega•3/13/24, 10:36 AM

that constructor

only you knowOP•3/13/24, 10:36 AM

I should use MongoDB class instead of IMongoDatabase right

Pobiega•3/13/24, 10:37 AM

the first two lines create a new instance, but you are injecting one. And locally creating the connection inside your repo is almost guaranteed to be a very bad idea

Pobiega•3/13/24, 10:37 AM

also, your repo is a singleton

Pobiega•3/13/24, 10:37 AM

a singleton with a database connection.... sounds like a recipe for trouble

PPobiega also, your repo is a singleton

only you knowOP•3/13/24, 10:37 AM

I should make it scope

PPobiega the first two lines create a new `IMongoDatabase` instance, but you are injectin...

only you knowOP•3/13/24, 10:39 AM

so I gotta call MongoDB directly because in that class I already created new client

Pobiega•3/13/24, 10:39 AM

do you know the difference between singleton, scoped and transient?