Book Image

Angular Services

Book Image

Angular Services

Overview of this book

A primary concern with modern day applications is that they need to be dynamic, and for that, data access from the server side, data authentication, and security are very important. Angular leverages its services to create such state-of-the-art dynamic applications. This book will help you create and design customized services, integrate them into your applications, import third-party plugins, and make your apps perform better and faster. This book starts with a basic rundown on how you can create your own Angular development environment compatible with v2 and v4. You will then use Bootstrap and Angular UI components to create pages. You will also understand how to use controllers to collect data and populate them into NG UIs. Later, you will then create a rating service to evaluate entries and assign a score to them. Next, you will create "cron jobs" in NG. We will then create a crawler service to find all relevant resources regarding a selected headline and generate reports on it. Finally, you will create a service to manage accuracy and provide feedback about troubled areas in the app created. This book is up to date for the 2.4 release and is compatible with the 4.0 release as well, and it does not have any code based on the beta or release candidates.
Table of Contents (15 chapters)
Angular Services
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface

Chapter 4.  The Rating Service - Data Management

So far we have collected news headlines from CNN and saved them to the Firebase Realtime Database successfully. In this chapter, we are going to implement a service that has three main responsibilities:

  • Create and save a rating logic

  • Query the recorded news

  • Calculate the rank and sort the collected items based on their rank

While doing these steps we will learn about how to query Firebase objects and extract the piece of data that we are looking for. But before we continue, please be advised that the purpose of the Ranking Service in our project is to help us to find which headline is worth investigation.

So basically it is just a helper and at the end of the day, you are the one who will decide which headline you should chose. In other words, in this chapter we will use the Rating service just to get some insight and find a direction. However, in the chapters to come - especially when we set everything in auto pilot mode - we will see how we...