Programming APIs with the Spark Web Framework
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Programming APIs with the Spark Web Framework

About the Book

Perhaps the singular most important choice an API developer can make is one of programming language and architecture. Choosing how an API will communicate with consumers, how security will be implemented, and how the API will function with other services is largely constrained by the language and methodology by which it is developed.

Throughout this eBook, we’ll discuss a Java framework called Spark, its basic use, history, and compare it with other languages and toolkits. We’ll highlight what makes Java Spark an incredibly functional and useful toolkit for crafting APIs, and provide some examples. We also demonstrate you how you can use this framework in Scala and Kotlin, two other languages that run on the Java Virtual Machine (JVM).

*All proceeds from the sale of this eBook will be donated to the Salvation Army in Sweden.

About the Author

Nordic APIs
Nordic APIs

In 2013, Nordic APIs was formed to help organizations become more innovative, lean, and efficient. Nordic APIs has grown into one of only a handful of all-­API-­related event series held anywhere in the world. After hosting more than a dozen events, the community has grown to include hundreds of international thought leaders. Through the global reach of its blog, Nordic APIs is connected to 10's of thousands of API practitioners from around the world. Visit for more information.

About the Contributors

Bill Doerrfeld
Bill Doerrfeld


Kristopher Sandoval
Kristopher Sandoval

Web Developer, Nordic APIs Blogger

Per Wendel
Per Wendel

Software Architect, Founder of Spark Java

Travis Spencer
Travis Spencer

CEO & Founder, Twobo Technologies

Table of Contents

  • Preface
  • 1. Introduction
  • 2. Using Spark to Create APIs in Java
    • 2.1 Introducing Spark
    • 2.2 More Complicated Example
    • 2.3 Templatized Responses
    • 2.4 Spark Compared
    • 2.5 Benefits of Spark
  • 3. Introducing Kotlin to the JVM
    • 3.1 Introducing the JVM
    • 3.2 Enter Kotlin
    • 3.3 Why Kotlin?
    • 3.4 Examples of Kotlin’s Syntax
    • 3.5 Functions and Constructors
    • 3.6 Named Arguments and Passing Function Literals
    • 3.7 Generics
    • 3.8 Data Classes
    • 3.9 Smart Casts
    • 3.10 Using Kotlin
    • 3.11 Converting Existing Code
    • 3.12 Compiling Kotlin
    • 3.13 Debugging
    • 3.14 Conclusion
  • 4. Building APIs on the JVM using Kotlin and Spark
    • 4.1 Recapped Intro to Spark
    • 4.2 Building a Robust API with Spark
    • 4.3 Templating in Kotlin
    • 4.4 Adding DI Capabilities to a Spark-based API
    • 4.5 Implementing API Logic in Controllers
    • 4.6 Conclusion and Next Steps
  • 5. Using Spark to Create APIs in Scala
    • 5.1 Reintroducing Spark
    • 5.2 Scala — It’s Origin and Purpose
    • 5.3 Why Scala? Why Not Java?
    • 5.4 Different, More Efficient Methods
    • 5.5 Scala Performance and Integration
    • 5.6 Conclusion
    • Resources
  • About Nordic APIs
    • API Themed Events
    • Follow the Nordic APIs Blog
    • More eBooks by Nordic APIs:
  • Endnotes

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