Go Programming Blueprints

Mat Ryer

• Verlag: Packt Publishing
• Jahr: 2015
• ISBN:
  9781783988020
• Thema: Informatica
• Thema: Sviluppo di applicazioni

Go Programming Blueprints

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Table of Contents

Go Programming Blueprints

Credits

About the Author

Acknowledgments

About the Reviewers

www.PacktPub.com

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Why subscribe?

Free access for Packt account holders

Preface

What this book covers

What you need for this book

Who this book is for

Conventions

Reader feedback

Customer support

Downloading the example code

Errata

Piracy

Questions

1. Chat Application with Web Sockets

A simple web server

Templates

Doing things once

Using your own handlers

Properly building and executing Go programs

Modeling a chat room and clients on the server

Modeling the client

Modeling a room

Concurrency programming using idiomatic Go

Turning a room into an HTTP handler

Use helper functions to remove complexity

Creating and using rooms

Building an HTML and JavaScript chat client

Getting more out of templates

Tracing code to get a look under the hood

Writing a package using TDD

Interfaces

Unit tests

Red-green testing

Implementing the interface

Unexported types being returned to users

Using our new trace package

Making tracing optional

Clean package APIs

Summary

2. Adding Authentication

Handlers all the way down

Making a pretty social sign-in page

Endpoints with dynamic paths

OAuth2

Open source OAuth2 packages

Tell the authentication providers about your app

Implementing external logging in

Logging in

Handling the response from the provider

Presenting the user data

Augmenting messages with additional data

Summary

3. Three Ways to Implement Profile Pictures

Avatars from the authentication server

Getting the avatar URL

Transmitting the avatar URL

Adding the avatar to the user interface

Logging out

Making things prettier

Implementing Gravatar

Abstracting the avatar URL process

The authentication service and avatar's implementation

Using an implementation

Gravatar implementation

Uploading an avatar picture

User identification

An upload form

Handling the upload

Serving the images

The Avatar implementation for local files

Supporting different file types

Refactoring and optimizing our code

Replacing concrete types with interfaces

Changing interfaces in a test-driven way

Fixing existing implementations

Global variables versus fields

Implementing our new design

Tidying up and testing

Combining all three implementations

Summary

4. Command-line Tools to Find Domain Names

Pipe design for command-line tools

Five simple programs

Sprinkle

Exercise – configurable transformations

Domainify

Exercise – making top-level domains configurable

Coolify

Synonyms

Using environment variables for configuration

Consuming a web API

Getting domain suggestions

Available

Composing all five programs

One program to rule them all

Summary

5. Building Distributed Systems and Working with Flexible Data

System design

Database design

Installing the environment

NSQ

NSQ driver for Go

MongoDB

MongoDB driver for Go

Starting the environment

Votes from Twitter

Authorization with Twitter

Extracting the connection

Reading environment variables

Reading from MongoDB

Reading from Twitter

Signal channels

Publishing to NSQ

Gracefully starting and stopping

Testing

Counting votes

Connecting to the database

Consuming messages in NSQ

Keeping the database updated

Responding to Ctrl + C

Running our solution

Summary

6. Exposing Data and Functionality through a RESTful Data Web Service API

RESTful API design

Sharing data between handlers

Wrapping handler functions

API key

Database session

Per request variables

Cross-browser resource sharing

Responding

Understanding the request

A simple main function to serve our API

Using handler function wrappers

Handling endpoints

Using tags to add metadata to structs

Many operations with a single handler

Reading polls

Creating a poll

Deleting a poll

CORS support

Testing our API using curl

A web client that consumes the API

An index page showing a list of polls

A page to create a new poll

A page to show details of the poll

Running the solution

Summary

7. Random Recommendations Web Service

Project overview

Project design specifics

Representing data in code

Public views of Go structs

Generating random recommendations

Google Places API key

Enumerators in Go

Test-driven enumerator

Querying the Google Places API

Building recommendations

Handlers that use query parameters

CORS

Testing our API

Web application

Summary

8. Filesystem Backup

Solution design

Project structure

Backup package

Obvious interfaces?

Implementing ZIP

Has the filesystem changed?

Checking for changes and initiating a backup

Hardcoding is OK for a short while

The user command-line tool

Persisting small data

Parsing arguments

Listing the paths

String representations for your own types

Adding paths

Removing paths

Using our new tool

The daemon backup tool

Duplicated structures

Caching data

Infinite loops

Updating filedb records

Testing our solution

Summary

A. Good Practices for a Stable Go Environment

Installing Go

Installing the C tools

Downloading and building Go from the source

Configuring Go

Getting GOPATH right

Go tools

Cleaning up, building, and running tests on save

Sublime Text 3

Summary

Index

Go Programming Blueprints

Copyright © 2015 Packt Publishing

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First published: January 2015

Production reference: 1200115

Published by Packt Publishing Ltd.

Livery Place

35 Livery Street

Birmingham B3 2PB, UK.

ISBN 978-1-78398-802-0

www.packtpub.com

Credits

Author

Mat Ryer

Reviewers

Tyler Bunnell

Michael Hamrah

Nimish Parmar

Commissioning Editor

Kunal Parikh

Acquisition Editor

Richard Brookes-Bland

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