Book Image

Learning Go Programming

Book Image

Learning Go Programming

Overview of this book

The Go programming language has firmly established itself as a favorite for building complex and scalable system applications. Go offers a direct and practical approach to programming that let programmers write correct and predictable code using concurrency idioms and a full-featured standard library. This is a step-by-step, practical guide full of real world examples to help you get started with Go in no time at all. We start off by understanding the fundamentals of Go, followed by a detailed description of the Go data types, program structures and Maps. After this, you learn how to use Go concurrency idioms to avoid pitfalls and create programs that are exact in expected behavior. Next, you will be familiarized with the tools and libraries that are available in Go for writing and exercising tests, benchmarking, and code coverage. Finally, you will be able to utilize some of the most important features of GO such as, Network Programming and OS integration to build efficient applications. All the concepts are explained in a crisp and concise manner and by the end of this book; you would be able to create highly efficient programs that you can deploy over cloud.
Table of Contents (18 chapters)
Learning Go Programming
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface

The io.Writer interface


The io.Writer interface, as shown in the following code, is just as simple as its reader counterpart:

type Writer interface { 
   Write(p []byte) (n int, err error) 
} 

The interface requires the implementation of a single method, Write(p []byte)(c int, e error), that copies data from the provided stream p and writes that data to a sink resource such as an in-memory structure, standard output, a file, a network connection, or any number of io.Writer implementations that come with the Go standard library. The Write method returns the number of bytes copied from p followed by an error value if any was encountered.

The following code snippet shows the implementation of the channelWriter type, a writer that decomposes and serializes its stream that is sent over a Go channel as consecutive bytes:

type channelWriter struct { 
   Channel chan byte 
} 
 
func NewChannelWriter() *channelWriter { 
   return &channelWriter{ 
   ...