feat: create API host helper and environment-specific API host strings

src/app/app.module.ts

@@ -3,6 +3,7 @@ import { NgModule } from '@angular/core';
 import { FormsModule } from '@angular/forms';
 import { HttpModule } from '@angular/http';
 
+import { APIHostProvider } from './helpers/api-host';
 import { AppComponent } from './app.component';
 import { FaceComponent } from './face/face.component';
 import { TweetComponent } from './tweet/tweet.component';
@@ -24,6 +25,7 @@ import { SvgComponent } from './svg/svg.component';
     HttpModule,
   ],
   providers: [
+    APIHostProvider,
     TwitterService,
   ],
   bootstrap: [AppComponent]

src/app/helpers/api-host.ts

@@ -0,0 +1,5 @@
+import { OpaqueToken } from '@angular/core';
+import { environment } from '../../environments/environment';
+
+export const APIHost = new OpaqueToken('APIHost');
+export const APIHostProvider = { provide: APIHost, useValue: environment.apiHost };

src/environments/environment.prod.ts

@@ -1,3 +1,4 @@
 export const environment = {
-  production: true
+  apiHost: 'http://api.trumpymctweetface.com',
+  production: true,
 };

src/environments/environment.ts

@@ -4,5 +4,6 @@
 // The list of which env maps to which file can be found in `.angular-cli.json`.
 
 export const environment = {
-  production: false
+  apiHost: 'http://localhost:5000',
+  production: false,
 };