Mastering Qlik Sense

Martin Mahler, Juan Ignacio Vitantonio

• Éditeur: Packt Publishing
• Année: 2018
• ISBN:
  9781782174875
• Édition: 1
• Sujet: Computer Science
• Sous-sujet: Data Visualisation

Master the capabilities of Qlik Sense to design and deploy solutions that address all the Business Intelligence needs of your organizationAbout This Book• Create compelling dashboards and visualizations with your data by leveraging Qlik Sense's self-service model• Perform data loading and model efficient solutions with faster performance and better governance• Master Qlik Sense's APIs and develop powerful mashups and fantastic extensions for visualizations and other components that run across all platformsWho This Book Is ForThis book is for Business Intelligence professionals and Data Analysts who want to become experts in using Qlik Sense. If you have extensively used QlikView in the past and are looking to transition to Qlik Sense, this book will also help you. A fundamental understanding of how Qlik Sense works and its features is all you need to get started with this book.What You Will Learn• Understand the importance of self-service analytics and the IKEA-effect• Explore all the available data modeling techniques and create efficient and optimized data models• Master security rules and translate permission requirements into security rule logic• Familiarize yourself with different types of Master Key Item(MKI) and know how and when to use MKI.• Script and write sophisticated ETL code within Qlik Sense to facilitate all data modeling and data loading techniques• Get an extensive overview of which APIs are available in Qlik Sense and how to take advantage of a technology with an API• Develop basic mashup HTML pages and deploy successful mashup projectsIn DetailQlik Sense is a powerful, self-servicing Business Intelligence tool for data discovery, analytics and visualization. It allows you to create personalized Business Intelligence solutions from raw data and get actionable insights from it.This book is your one-stop guide to mastering Qlik Sense, catering to all your organizational BI needs. You'll see how you can seamlessly navigate through tons of data from multiple sources and take advantage of the various APIs available in Qlik and its components for guided analytics. You'll also learn how to embed visualizations into your existing BI solutions and extend the capabilities of Qlik Sense to create new visualizations and dashboards that work across all platforms. We also cover other advanced concepts such as porting your Qlik View applications to Qlik Sense, and working with Qlik Cloud. Finally, you'll implement enterprise-wide security and access control for resources and data sources through practical examples.With the knowledge gained from this book, you'll have become the go-to expert in your organization when it comes to designing BI solutions using Qlik Sense.Style and approachThis book provides in-depth knowledge on complex visualization processes. This guide will take you straight to complex implementation techniques.While covering the concepts, the use cases will help you understand how they work and how to utilize them.

Creating Extensions in Qlik Sense

Extensions in Qlik Sense offer the beautiful opportunity to extend your Qlik Sense user experience by creating bespoke data visualizations, objects, or control elements that interact with the powerful Qlik data engine. It's mainly useful when you have a particular use case in mind, or you have seen a great visualization that you would like to implement in Qlik to visualize your data. Furthermore, sometimes advanced use cases exceed the native capabilities of Qlik Sense and require you to introduce custom objects to facilitate some niche requirements.

Luckily, with Qlik Sense and a basic knowledge of web development, this is not very difficult to achieve, and, with a little bit of practice, the possibilities on top of the Qlik Engine have no limits. To get you there, you have so far in this book internalized the basic concepts of web development, which will be vital to understanding this chapter. As such, it will not go into too much detail on how and why the code is used in specific ways. It will focus more on actually introducing you to web development but within Qlik Sense, bringing the structure of a Qlik extension closer to you and deepening your knowledge of Qlik APIs, in particular, the Extension API.

In detail, this chapter will cover the following relevant aspects:

• Structuring the code of your extension project
• Best practice and the dos and don'ts of extending your Qlik Sense apps
• Designing and creating a user-friendly property panel to change the settings of your charts dynamically
• The details of a qHyperCube structure, its definition, and the returned results
• A step-by-step guide to creating a D3 bar chart example from scratch
• A step-by-step guide to creating a drop-down component example from scratch for selecting filter values
• Introduction to some platforms where you can find useful and open source code for your projects

Structuring your code

It's always tempting to just go ahead and start coding right away, and I won't deny it's the most fun part of any project. However, as your extension projects grow and become more complicated, the technical debt of quick wins and fast fixes will take its toll. As such, it's important to begin each extension project by defining a proper code structure to ensure the project is prepared to scale.

To begin with, in each extension, you can expect to have the following basic files at a minimum. We'll be using MasteringQS as a sample extension name:

• MasteringQS.qext (required)
• MasteringQS.js (required)
• MasteringQS.css (optional)
• wbfolder.wbl (optional)

While some files are optional, for the purposes of this chapter, we will include them.

The .qext file

The .qext file is the definition file of each extension that defines its metadata and how it's being read by the Qlik Sense Repository as well as its Asset or Library Panel. This file ultimately determines how it's displayed on the left-hand panel within edit mode, and it's important to note that it has to have the same filename as the corresponding primary JavaScript file.

The .qext file and main JavaScript of the extension must have the same name.

The qext file is a simple text file and, as such, can be edited with any notepad, and needs to define its metadata in a JSON format, for example:

{ 
 "name": "Mastering QS Example", 
 "description": "This is a description", 
 "preview": "masteringqs.png", 
 "type": "visualization", 
 "version": 1, 
 "author": "Martin Mahler" 
}

The preceding information is a shortened version of what can be defined in detail:

Name	Options	Description
name	N/A	Mandatory. Name of the visualization displayed in the library. It is recommended to use a unique name for the visualization to avoid interference with other visualizations that may have the same name.
type	N/A	Mandatory. Should always be visualization.
description	N/A	Description displayed in the library. The default is extension.
extension		N/A
bar-chart-vertical		N/A
line-chart		N/A
pie-chart		N/A
gauge-chart		N/A
scatter-chart		N/A
text-image		N/A
table		N/A
list		N/A
filterpane		N/A
treemap		N/A
preview	[CustomImage].png	Defines the preview image to be used. The preview image is displayed in a popup when you select the visualization in the library. You can define a custom preview image file. It must be of .png file format. If the preview is undefined, the icon definition will be used.
version	NA	Defines your individual version handling of the extension. This setting is manually defined.
author	NA	Defines the author of the visualization. This parameter is manually assigned.

In addition to the preceding, you can freely leverage the .qext file to pass on additional information to the extension. While not used in Qlik Sense itself, they can later be called upon in the qHyperCube. Other metadata that is typically added is license, release date, home page, dependencies (QS version require...