Book Image

.Go Programming Blueprints - Second Edition

By : Mat Ryer
Book Image

.Go Programming Blueprints - Second Edition

By: Mat Ryer

Overview of this book

Go is the language of the Internet age, and the latest version of Go comes with major architectural changes. Implementation of the language, runtime, and libraries has changed significantly. The compiler and runtime are now written entirely in Go. The garbage collector is now concurrent and provides dramatically lower pause times by running in parallel with other Go routines when possible. This book will show you how to leverage all the latest features and much more. This book shows you how to build powerful systems and drops you into real-world situations. You will learn to develop high quality command-line tools that utilize the powerful shell capabilities and perform well using Go's in-built concurrency mechanisms. Scale, performance, and high availability lie at the heart of our projects, and the lessons learned throughout this book will arm you with everything you need to build world-class solutions. You will get a feel for app deployment using Docker and Google App Engine. Each project could form the basis of a start-up, which means they are directly applicable to modern software markets.
Table of Contents (19 chapters)
Go Programming Blueprints Second Edition
About the Author
About the Reviewer


Now that we have modeled questions and answers in our application, it's time to think about how voting might work.

Let's design it a little:

  • Users vote answers up and down based on their opinion of them

  • Answers are ordered by their score so the best ones appear first

  • Each person is allowed one vote per answer

  • If a user votes again, they should replace their previous vote

We will make use of a few things we have learned so far in this chapter; transactions will help us ensure the correct score is calculated for answers, and we'll use predictable keys again to ensure that each person gets only one vote per answer.

We will first build a structure to represent each vote and use field tags to be a little more specific about how we want the data store to index our data.


Reads from Google Cloud Datastore are extremely fast due to the extensive use of indexes. By default, every field in our structure is indexed. Queries that attempt to filter on fields that aren't indexed will fail (the method...