Angular cli generate a service and include the provider in one step

Question

It is possible generate a service with angular cli and add it as a provider in the app.module.ts in a single step or using an special option in the ng g service command?

When a execute:

$ ng g service services/backendApi installing service   create src/app/services/backend-api.service.spec.ts   create src/app/services/backend-api.service.ts   WARNING Service is generated but not provided, it must be provided to be used 

Next to it, (and according to the WARNING message) I usually add it to provider section on app.module.ts using the text editor:

@NgModule({   declarations: [     AppComponent,     ...   ],   imports: [     ....   ],   providers: [BackendApiService],   bootstrap: [AppComponent] }) 

It is possible to do it with a single step, to automatize this?

Answer 1

Actually, it is possible to provide the service (or guard, since that also needs to be provided) when creating the service.

The command is the following...

ng g s services/backendApi --module=app.module

Edit

It is possible to provide to a feature module, as well, you must give it the path to the module you would like.

ng g s services/backendApi --module=services/services.module

Answer 2

Angular 6+ Singleton Services

The recommended approach for a singleton service for Angular 6 and beyond is :

import { Injectable } from '@angular/core';  @Injectable({   providedIn: 'root', }) export class UserService { } 

In fact the CLI --module switch doesn't even exist any more for registering a service at the app level because it doesn't need to modify app.module.ts anymore.

This will create the above code, without needing to specify a module.

ng g s services/user 

So if you don't want your service to be a singleton you must remove the providedIn code yourself - and then add it manually to providers for a component or lazy loaded module. Doesn't look like there is currently a switch to not generate the providedIn: 'root' part so you need to manually remove it.