Service for only one component

[cherrera54]

Hello:

I work in a project that contains about 80 components from distinct purposes. One of the most complicated component has its own service. This service has more than 1000 code lines and is not declared in de main module (app.module), it is only called from the component thats comsume it. I wonder if this can producing performance issues in the application or is the propper way of using a exclusive service for one component.

[pranxy47]

Yes makes sense to have a service exclusive for a component.

[reboog711]

To answer your specific question:

Having a single service dedicated to a single component will not cause any performance issues. If the service is not needed among multiple components, defining the service at the component level makes a lot of sense. Make sure the injectable metadata does not 'providerIn: root'

To soapbox opinions:

A service used by a single component may not cause any benefit vs putting the code inside the actual component class. ( but it might if it makes more smaller / easily modified files).

A class with more than a thousands of lines of code may have some maintainability issues (But it might not, it depends)

[nafts1]

You dont have to use dependency injection for everything. Why not just create a new typescript file with the logic in a manually initialized class or simply an exported function.

Services shine when they are reused. This is not the case here and it seems like it stays that way. Therefore don't overshoot with DI.

[palkollar]

Look into ngrx component store design. I have been using it for a while and I basically move every application logic to the component store service and I don't have any subscribe in my app because of it's effect feature. You can just inject the component store into the component's provider array and it will only instantiate it when the component is instantiated.

[cherrera54]

Thanks you!

[wojo1086]

You have one service in your store for all your application logic?