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
Credits
About the Author
Acknowledgments
About the Reviewer
www.PacktPub.com
Preface

The daemon backup tool


The backup tool, which we will call backupd, will be responsible for periodically checking the paths listed in the filedb database, hashing the folders to see whether anything has changed, and using the backup package to actually perform the archiving of the folders that need it.

Create a new folder called backupd alongside the backup/cmds/backup folder, and let's jump right into handling the fatal errors and flags:

func main() { 
  var fatalErr error 
  defer func() { 
    if fatalErr != nil { 
      log.Fatalln(fatalErr) 
    } 
  }() 
  var ( 
    interval = flag.Duration("interval", 10 * time.Second, "interval between 
    checks") 
    archive  = flag.String("archive", "archive", "path to archive location") 
    dbpath   = flag.String("db", "./db", "path to filedb database") 
  ) 
  flag.Parse() 
} 

You must be quite used to seeing this kind of code by now. We defer the handling of fatal...