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 (13 chapters)

Building a gRPC client


Unlike JSON/HTTP services, gRPC services aren't easy for humans to interact with. They're really intended as machine-to-machine protocols, and so we must write a program if we wish to use them.

To help us do this, we are first going to add a new package inside our vault service called vault/client/grpc. It will, given a gRPC client connection object that we get from Google's grpc package, provide an object that performs the appropriate calls, encoding and decoding, for us, all hidden behind our own vault.Service interface. So, we will be able to use the object as though it is just another implementation of our interface.

Create new folders inside vault so that you have the path of vault/client/grpc. You can imagine adding other clients if you so wish, so this seems a good pattern to establish.

Add the following code to a new client.go file:

func New(conn *grpc.ClientConn) vault.Service { 
  var hashEndpoint = grpctransport.NewClient( 
    conn, "Vault", "Hash", 
    vault...