Book Image

Apache Spark 2.x Cookbook

By : Rishi Yadav
Book Image

Apache Spark 2.x Cookbook

By: Rishi Yadav

Overview of this book

While Apache Spark 1.x gained a lot of traction and adoption in the early years, Spark 2.x delivers notable improvements in the areas of API, schema awareness, Performance, Structured Streaming, and simplifying building blocks to build better, faster, smarter, and more accessible big data applications. This book uncovers all these features in the form of structured recipes to analyze and mature large and complex sets of data. Starting with installing and configuring Apache Spark with various cluster managers, you will learn to set up development environments. Further on, you will be introduced to working with RDDs, DataFrames and Datasets to operate on schema aware data, and real-time streaming with various sources such as Twitter Stream and Apache Kafka. You will also work through recipes on machine learning, including supervised learning, unsupervised learning & recommendation engines in Spark. Last but not least, the final few chapters delve deeper into the concepts of graph processing using GraphX, securing your implementations, cluster optimization, and troubleshooting.
Table of Contents (19 chapters)
Title Page
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface

Loading and saving data using the JSON format


JSON is a lightweight data-interchange format. It is based on a subset of the JavaScript programming language. JSON's popularity is directly related to XML getting unpopular. XML was a great solution to provide a structure to the data in plain text format. With time, XML documents became heavier, and the overhead was not worth it.

JSON solved this problem by providing a structure with minimal overhead. Some people call JSON fat-free XML.

JSON's syntax follows these rules:

  • Data is in the form of key-value pairs:
        "firstName" : "Bill"
  • There are four datatypes in JSON:
    • String ("firstName" : "Barack")
    • Number ("age" : 56)
    • Boolean ("alive": true)
    • null ("manager" : null)
  • Data is delimited by commas
  • Curly braces {} represents an object:
        { "firstName" : "Bill", "lastName": "Clinton", "age": 70 }
  • Square brackets [] represent an array:
        [{ "firstName" : "Bill", "lastName": "Clinton", "age": 70 }
          {"firstName": "Barack","lastName": "Obama...