Angular 2 - No provider for Service - dependency-injection

Question

I've been trying to troubleshoot a strange problem with angular 2 where it isn't detecting my provider declaration, but nothing is working. I can't even replicate it in plunkr.
I'm using angular 2 rc 3 with router 3.0 alpha.8.
Error message is: ORIGINAL EXCEPTION: No provider for TestService!
app.routes.ts:
import { provideRouter, RouterConfig } from '#angular/router';
import { HomeComponent } from './app/home/home.component';
import { LogInComponent } from './app/log-in/log-in.component';
import { SignUpComponent } from './app/sign-up/sign-up.component';
export const routes: RouterConfig = [
{ path: '', component: HomeComponent },
{ path: 'log-in', component: LogInComponent },
{ path: 'sign-up', component: SignUpComponent }
];
export const APP_ROUTER_PROVIDERS = [
provideRouter(routes)
];
main.ts:
import { bootstrap } from '#angular/platform-browser-dynamic';
import { enableProdMode } from "#angular/core";
import { AppComponent } from './app/app.component';
import { APP_ROUTER_PROVIDERS } from './app.routes';
// enableProdMode();
bootstrap(AppComponent, [
APP_ROUTER_PROVIDERS
])
.catch(error => console.log(error));
app/app.component.ts:
import { Component } from '#angular/core';
import { ROUTER_DIRECTIVES } from '#angular/router';
import { TestService } from './shared/test.service';
#Component({
selector: 'my-app',
template: `
<div id="menu">
<a [routerLink]="['/sign-up']"><button>Sign Up</button></a>
</div>
<router-outlet></router-outlet>
`,
directives: [ROUTER_DIRECTIVES],
providers: [TestService]
})
export class AppComponent {
constructor() { }
}
app/sign-up/sign-up.component.ts:
import { Component } from '#angular/core';
import { ROUTER_DIRECTIVES } from '#angular/router';
import { TestService } from '../shared/test.service';
#Component({
selector: 'sign-up',
template: `<h1>Sign up!</h1>`,
directives: [ROUTER_DIRECTIVES]
})
export class SignUpComponent {
constructor(private testService: TestService) {
this.testService.test('works?');
}
}
app/shared/test.service.ts:
import { Injectable } from '#angular/core';
#Injectable()
export class TestService {
constructor() { }
test(message: string) {
console.log(message);
}
}
So, I'm providing the testservice in the base component (app.component.ts) because I want all my components to access the same instance. However, when I navigate to sign-up, I get the no provider for testservice error. If I provide the TestService within the sign-up component, this then works:
import { Component, OnInit } from '#angular/core';
import { ROUTER_DIRECTIVES } from '#angular/router';
import { TestService } from '../shared/test.service';
#Component({
selector: 'sign-up',
template: `<h1>Sign up!</h1>`,
directives: [ROUTER_DIRECTIVES],
providers: [TestService]
})
export class SignUpComponent implements OnInit {
constructor(private testService: TestService) { }
ngOnInit() { }
}
However, I need the same instance accessible throughout my app, so how can I inject this at the main component level?
I even tried replicating this app-level service providing with plunkr with the same version of everything, but it doesn't seem to give me the same error...
http://plnkr.co/edit/5bpeHs72NrlyUITCAJim?p=preview

Answer 1

Injecting something on the app level is done in bootstrap:
main.ts:
import { TestService } from '../shared/test.service';
bootstrap(AppComponent, [
APP_ROUTER_PROVIDERS, TestService
])

Answer 2

For me, some references to the "services" folder were "Services". When I made them all "services" (lower case), it worked.
For example:
import {ApiService} from "./Services/api.service";
didn't work, but this worked:
import {ApiService} from "./services/api.service";

Answer 3

To All future readers - and this is correct for angular 2.0.0 rc-4:
make sure that you follow the below folder structure:
root:
index.html
package.json
systemjs.config.js
tsconfig.json (if using TypeScript)
typings.json
app (folder):
- main.js (the root script for your app)
- app.component.js (the root component for the entire app)
This is crucial for the hierarchical injection to properly scope and identify providers.
Also, and this is very important - if still encountering problems and you are using TypeScript or any other transpiled language- delete any artifacts which your transpiler produces for every associated class in the problematic object graph - this, and the OP's answer eventually helped in my case (*.map.js and *.js files deleted and re-transpiled).

Answer 4

It was a configuration issue after all, and a completely elusive one at that.
Per the ang2 style guide, I had my main.ts one folder up from my main app folder, and in systemjs.config I had to declare the main for app as '../main.js'. When I moved the main file to the root app folder and changed the package declaration in systemjs to 'main.js' it worked.
The odd thing is everything else worked, right up until I try to utilize hierarchical dependency injection.