Add data.service.ts

src/app/core/data.service.ts

 import { identifierModuleUrl } from '@angular/compiler';
 import { Injectable } from '@angular/core';
-import { HttpClientModule } from '@angular/common/http';
 import { Router } from '@angular/router';
-import { Observable } from 'rxjs';
-
+import { HttpClient, HttpHeaders } from '@angular/common/http';
 import { ConfigService } from './config.service';
+import { Response, ResponseContentType } from '@angular/http';
+import { Observable } from 'rxjs';
+import { catchError, map, tap } from 'rxjs/operators';
+import { throwError } from 'rxjs';
 
 @Injectable()
 export class DataService {
 	private api: string;
+	private coursesUrl = 'https://dev.enroll.wisc.edu/api/planner/v1/degreePlan/519261/courses';
+	private log: any;
 
-	constructor(private http: HttpClientModule, private configService: ConfigService) {
+	constructor(private http: HttpClient, private configService: ConfigService) {
 		this.api = this.configService.apiUrl;
 	}
+
+	getCourseData() {
+		return this.http
+			.get(this.coursesUrl)
+			// .subscribe(
+			// 	data => console.log('data: ', data), // success path
+			// 	error => console.log('error: ', error) // error path
+			// );
+			.pipe(
+				map(this.extractData),
+				catchError(this.errorHandler)
+		);
+	}
+
+	private extractData(res: Response) {
+		return res.text() ? res.json() : {};
+	}
+
+	private errorHandler(error: Response) {
+		// console.error(error);
+		return throwError(error || 'Server Error');
+	}
+
 }