Swift^™ in the Cloud

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About the Authors

Leigh Williamson is an IBM Distinguished Engineer who has been working in the company’s Austin, Texas lab since 1989, contributing to major software projects for IBM, including OS/2, DB2, AIX, Java, WebSphere, Rational, and MobileFirst products. He is currently leading a cross-disciplinary team of IBM Cloud Consultants who assist clients with cloud computing strategy and execution. Leigh is an active mentor and leader in the IBM technical community, working with international mentees; working in the Advanced Technical Eminence program; leading multiple patent brainstorming teams; publishing technical blogs and articles; conducting external broadcast webinars; and speaking at IBM and non-IBM conferences.

This is the fourth IBM Press book on which Leigh has collaborated over the past 15 years, with works covering Java standards, WebSphere Application Server, and enterprise-class mobile application development. He holds a B.S. in Computer Science from Nova University and an M.S. in Computer Engineering from The University of Texas at Austin.

You can follow Leigh on Twitter at @leighawillia. His LinkedIn address is https://www.linkedin .com/in/leigh-williamson-9048654.

John Ponzo is an IBM Fellow and Chief Technology Officer for Mobile who has shaped the future of IBM business in mobile computing and delivered innovative products and services to web browser and server-based standards. He is a pioneer in technology that promotes end-user interaction through mobility, web programming, web application middleware, and software tools. John led the development of key software technologies including HTML/JavaScript runtime libraries, XML middleware, web services runtime libraries, Eclipse Web Integration, and Web 2.0 enterprise collaboration services. He also authored the “Enterprise Mobile” and the “Mobile First” theses that are the cornerstone of mobile strategy and execution at IBM. John also serves as the IBM technology ambassador to Kenya.

John is the primary technical collaborator between Apple and IBM in the effort to define and enhance the Swift programming language for both mobile client development and cloud services development.

Patrick Bohrer is a Distinguished Engineer in the IBM Cloud division. His responsibilities include serving as the technical lead for the company’s global efforts around Swift@IBM (developer.ibm .com/swift). He formerly served as the technical lead of the Mobile Innovation Lab in Austin, Texas. Patrick also helped lead IBM Research’s Mobile Research agenda after co-leading the 2012 Global Technology Outlook topic entitled “Mobile First,” which helped set the technical direction for current mobile and cloud efforts at IBM. Patrick received a B.A in Computer Science from The University of Texas at Austin.

Karl Weinmeister is the Program Director for Swift@IBM Engineering, based in Austin, Texas. He is passionate about improving people’s lives and experiences with technology. In his role, he has helped to enable Swift to extend from its mobile roots to become a full-stack language ecosystem.

Previously, Karl led engineering for the IBM Mobile Innovation Lab. He is a diehard Duke basketball fan and enjoys spending time with his family.

Ricardo Olivieri is a Senior Software Engineer at Swift@IBM Engineering. His areas of expertise include gathering and analyzing business requirements, architecting, designing, and developing software applications. Ricardo has extensive experience in the complete software development cycle and related processes, especially in Agile methodologies.

Ricardo has several years of experience in Java development as well as in Groovy, Perl, and Python development, with a strong background in back-end (server-side, business logic, SQL, and NoSQL databases) and front-end development. Several years ago, Ricardo added Business Process Manager (BPM) design and development to his skill set, which allowed him to assume the role of BPM consultant and developer using IBM Business Process Manager. While working at the Mobile Innovation Lab, Ricardo gained valuable skills and knowledge in the iOS and Android ecosystems.

Ricardo is now mainly focused on the adoption of the Swift language on the server and the IBM cloud, Bluemix. He has a B.S. in Computer Engineering from the University of Puerto Rico, Mayagüez Campus.

Samuel (Shmuel) Kallner is a Senior Technical Staff Member in the Smart Client Platforms group at the IBM Research Lab in Haifa, Israel. He is currently the Technical Lead of the Kitura project. Shmuel has over thirty years of experience at IBM working on a wide variety of projects including mobile apps, web-based end-user application development environments, mobile app developer tools, both sides of client-server–based applications, and more.

Credits

Executive Editor

Jim Minatel

Project Editor

Adaobi Obi Tulton

Technical Editor

Matthew Perrins

Production Editor

Dassi Zeidel

Copy Editor

Marylouise Wiack

Production Manager

Katie Wisor

Manager of Content Development and Assembly

Mary Beth Wakefield

Marketing Manager

Christie Hilbrich

Professional Technology & Strategy Director

Barry Pruett

Business Manager

Amy Knies

Project Coordinator, Cover

Brent Savage

Proofreader

Nancy Carrasco

Indexer

Johnna VanHoose Dinse

Cover Designer

Wiley

Cover Image

Acknowledgments

Many thanks to everyone at Wiley Publishing for their outstanding work on this project: to Jim Minatel for encouraging us to take this book concept forward and for yet again supporting the realization of a book that engages in deeper learning; to Adaobi Obi Tulton, the project editor, for driving this project to completion in the most efficient way possible—it was a real pleasure to work with such an accomplished and adept editor; to Marylouise Wiack, the copy editor, for translating this book into readable prose; and to Dassi Zeidel, the production editor, for bringing everything together to create a final, polished product.

Sincere thanks go to Matthew Perrins, the technical editor, for the incredible amount of work and personal time he selflessly put into ensuring that the content in this book can be utilized seamlessly by readers. Also, thanks to Steven Stansel, who was instrumental in formulating the original concept and proposal for the book. Brian White Eagle provided invaluable assistance with peering over the horizon in Chapter 9. And Shereen Ghobrial contributed the bulk of the mainframe-related content.

The biggest thank-you must, of course, go to our own families. This book was written over six months, predominantly at night and over weekends and holidays. In addition to sharing us with extremely demanding full-time jobs, our families made further sacrifices to enable us to spend time on this project.

Contents

About the Authors

About the Technical Editor

Credits

Acknowledgments

Introduction

IBM, Apple, and Swift
Scope of This Book

Chapter 1 Swift.org, the Open Source Project

What’s Included
How to Get Involved
Swift Evolution and Roadmap
Binary Downloads
Summary
Notes

Chapter 2 A Swift Sandbox in the Cloud

The IBM Cloud Platform
Getting Started
IBM Swift Package Catalog and Sandbox
Summary

Chapter 3 A Basic Introduction to Swift

Background
Let’s Get Coding!
The Language Landscape
Language Timeline
Summary

Chapter 4 The IBM Bluemix Buildpack for Swift

Cloud Foundry Buildpacks
Working with the IBM Bluemix Buildpack for Swift
Examples of Using the IBM Bluemix Buildpack for Swift
Using the Latest Code of the IBM Bluemix Buildpack for Swift
Summary

Chapter 5 Using Containers on Bluemix to Run Swift Code

Docker Images for Swift
Installing Docker
Using Docker as a Development Tool
Why Use Containers on Bluemix?
Running Your Docker Image in the Bluemix Cloud
High Availability in Kubernetes Clusters
Binding Bluemix Services to IBM Containers
Summary

Chapter 6 Swift Package Management

Swift Package Manager
Swift Package Catalog
Summary

Chapter 7 Swift and Kitura for Web Applications

Kitura
Kitura and Data Access
Summary
Notes

Chapter 8 Serverless Programming with Swift

Microservices and Serverless Computing
Swift and OpenWhisk
Summary

Chapter 9 Over the Horizon: Where Do We Go from Here?

Bringing Swift to the Server
Expanding the Range of Swift
Swift DevOps
Summary

EULA

List of Illustrations

Introduction

Figure 1: Popularity of the Swift programming language
Figure 2: Benefits of Swift compared with other languages
Figure 3: An overview of IBM involvement in major programming language evolution
Figure 4: Comparison of client and server elements for Swift
Figure 5: End-to-end Swift development

Chapter 1

Figure 1-1: One of the Swift.org source repositories
Figure 1-2: Email list signup page for the Swift General Interest group
Figure 1-3: Sign-up web page for a Swift JIRA bug-tracking account
Figure 1-4: Swift.org bug-tracking dashboard and login page
Figure 1-5: Swift.org bug tracking—what would you like to do now?
Figure 1-6: Swift.org bug-tracking Projects list
Figure 1-7: Swift.org bug tracking, showing a list of Kanban boards
Figure 1-8: Swift.org bug tracking, showing the Kanban board for all projects
Figure 1-9: Swift Toolchain Installer showing signature detail

Chapter 2

Figure 2-1: IBM Bluemix cloud platform login page
Figure 2-2: Typical Bluemix cloud platform user dashboard
Figure 2-3: IBM Bluemix catalog cloud infrastructure services view
Figure 2-4: Partial list of boilerplate cloud application templates in Bluemix catalog
Figure 2-5: List of DevOps development tools available in Bluemix catalog
Figure 2-6: List of Data and Analytics services available in Bluemix catalog
Figure 2-7: Watson Cognitive application services shown in Bluemix catalog
Figure 2-8: Application Services available in the Bluemix catalog
Figure 2-9: Swift “Hello world!” program shown in the Swift Sandbox
Figure 2-10: Loading sample Swift code into the Sandbox
Figure 2-11: Signing in to the Swift Sandbox
Figure 2-12: Saving your code in the Swift Sandbox
Figure 2-13: Share your code from the Swift Sandbox
Figure 2-14: Accessing your saved code from within the Swift Sandbox
Figure 2-15: Reloading your saved code in the Swift Sandbox
Figure 2-16: Selecting the version of Swift to use for the Sandbox
Figure 2-17: Running your Swift Sandbox code on a mainframe computer
Figure 2-18: Swift Package Catalog page for the HeliumLogger package
Figure 2-19: Try a Swift package in the Swift Sandbox
Figure 2-20: Swift package and its sample loaded into the Swift Sandbox
Figure 2-21: What’s new in the Swift Sandbox
Figure 2-22: Providing feedback for the Swift Sandbox

Chapter 3

Figure 3-1: A simple Swift program in the Swift Sandbox environment
Figure 3-2: Swift code accessing C language libraries in the Swift Sandbox
Figure 3-3: Swift concurrency demonstration in the Swift Sandbox
Figure 3-4: Swift memory management example shown in the Swift Sandbox
Figure 3-5: Swift language performance compared with other languages
Figure 3-6: Swift memory usage measurement compared with other languages
Figure 3-7: Swift language memory performance over time compared to other languages
Figure 3-8: The timeline for Swift language evolution

Chapter 4

Figure 4-1: GitHub repository for the IBM Bluemix buildpack for Swift
Figure 4-2: Running Swift HelloWorld on Bluemix
Figure 4-3: The Deploy to Bluemix button on the Swift HelloWorld application README file
Figure 4-4: Deploying the Swift HelloWorld app using the Deploy to Bluemix button
Figure 4-5: Bluemix DevOps Toolchain for the Swift HelloWorld app
Figure 4-6: Swift HelloWorld app successfully deployed to Bluemix using the Deploy to Bluemix button
Figure 4-7: Running Kitura Starter on Bluemix
Figure 4-8: The Deploy to Bluemix button on the Kitura Starter application README file
Figure 4-9: Deploying Kitura Starter using the Deploy to Bluemix button
Figure 4-10: List of service offerings in Bluemix
Figure 4-11: Landing page for the BluePic application
Figure 4-12: The Deploy to Bluemix button on the BluePic application README file
Figure 4-13: Deploying BluePic using the Deploy to Bluemix button
Figure 4-14: Bluemix DevOps Toolchain for BluePic

Chapter 5

Figure 5-1: Using your browser to access the Kitura Starter application running inside a Docker container
Figure 5-2: The Kitura Starter application running inside a Kubernetes cluster
Figure 5-3: Accessing the Kubernetes dashboard through the proxy agent
Figure 5-4: List of secrets for the Kubernetes cluster, swift-cluster
Figure 5-5: Secret details for the binding-kitura-object-storage secret

Chapter 6

Figure 6-1: The Xcode developer tool with a generated Swift project open for editing
Figure 6-2: The Popular Packages list from the IBM Swift Package Catalog
Figure 6-3: A view of the JSON category on the IBM Swift Package Catalog
Figure 6-4: Search Results for Kitura in the IBM Swift Package Catalog
Figure 6-5: The package details page
Figure 6-6: The Dependency Visualization view of the IBM Swift Package Catalog
Figure 6-7: The Try in Sandbox button enables users to try out a package.
Figure 6-8: Users can select from a variety of samples available.
Figure 6-9: After selecting a sample, the user can run the code in the IBM Swift Sandbox.

Chapter 7

Figure 7-1: The Kitura default root page
Figure 7-2: Library’s main.swift shown in XCode
Figure 7-3: API documentation for Kitura shown in XCode
Figure 7-4: Adding a book to the library using curl
Figure 7-5: Fetching all of the books in the library using curl
Figure 7-6: Searching for books authored by Tester 2
Figure 7-7: Retrieving books by id
Figure 7-8: Retrieving a book with a non-integer id
Figure 7-9: The library server crashing when an invalid id was sent in a request

Chapter 8

Figure 8-1: Comparing monolithic application scaling with microservices scaling
Figure 8-2: The basic OpenWhisk architecture
Figure 8-3: The OpenWhisk service icon in the IBM Bluemix Catalog page
Figure 8-4: The home page for the OpenWhisk service in IBM Bluemix
Figure 8-5: The Develop page for OpenWhisk event-driven programming
Figure 8-6: Click the Create an Action button to begin the process.
Figure 8-7: Name your OpenWhisk action and select the Swift v3 execution runtime.
Figure 8-8: Select the sample action template for your Swift OpenWhisk action.
Figure 8-9: The OpenWhisk action editor window with Swift v3 source code
Figure 8-10: The Invoking an Action web page for your Swift v3 OpenWhisk action
Figure 8-11: The Invocation Console for your example Swift OpenWhisk action
Figure 8-12: Change the input value to be sent to the action.
Figure 8-13: Output displayed for another invocation of the Swift action
Figure 8-14: Add print statements to the action source code.
Figure 8-15: The Console output window showing debug print log data
Figure 8-16: The button on the OpenWhisk home page for downloading the CLI
Figure 8-17: The Bluemix web page to access the OpenWhisk CLI
Figure 8-18: A graphical representation of the automated OpenWhisk action trigger
Figure 8-19: Monitoring your OpenWhisk activity in the Bluemix console
Figure 8-20: The expanded Activity Log view for automated OpenWhisk actions
Figure 8-21: A graphical representation of the new sequence of multiple actions
Figure 8-22: The Activity Log showing the echo action in the sequence of automated actions

Chapter 9

Figure 9-1: The IBM Cloud Tools for Swift web page
Figure 9-2: The Welcome screen for IBM Cloud Tools for Swift
Figure 9-3: Switching between different IBM Bluemix organizations in ICT
Figure 9-4: Selecting a new project in IBM Cloud Tools
Figure 9-5: ICT view of a project—both client and server components
Figure 9-6: Viewing the status of cloud deployment from ICT
Figure 9-7: Monitoring the Swift cloud application from ICT
Figure 9-8: Running both parts of an application—mobile app and cloud services
Figure 9-9: Embedding live Swift code into a web page
Figure 9-10: Architecture for Swift on System z