While dependency injection and many of the other programming concepts discussed in this book are not simple or intuitive, this book introduces them with little assumed knowledge.

That said, the following is assumed:

• You have a basic level of experience with building and testing Go code.
• You are comfortable with the idea of objects/classes due to prior experience with Go or an object-oriented language, such as Java or Scala.

Additionally, it would be beneficial to have at least a passing understanding of building and consuming HTTP-based REST APIs. In Chapter 4, Introduction to the ACME Registration Service, we will introduce an example REST service that will form the basis for many of the examples in the book. To be able to run this sample service, you will need to be able to install and configure a MySQL database service on your development environment and be able to customize the supplied configuration to match your local environment. All of the commands provided in this book were developed and tested under OSX and should work without modification on any Linux- or Unix-based system. Developers with Windows-based development environments will need to adjust the commands before running them.

You can download the example code files for this book from your account at www.packt.com. If you purchased this book elsewhere, you can visit www.packt.com/support and register to have the files emailed directly to you.

You can download the code files by following these steps:

1. Log in or register at www.packt.com.
2. Select the SUPPORT tab.
3. Click on Code Downloads & Errata.
4. Enter the name of the book in the Search box and follow the onscreen instructions.

Once the file is downloaded, please make sure that you unzip or extract the folder using the latest version of:

• WinRAR/7-Zip for Windows
• Zipeg/iZip/UnRarX for Mac
• 7-Zip/PeaZip for Linux

The code bundle for the book is also hosted on GitHub at https://github.com/PacktPublishing/Hands-On-Dependency-Injection-in-Go. In case there's an update to the code, it will be updated on the existing GitHub repository.

We also have other code bundles from our rich catalog of books and videos available at https://github.com/PacktPublishing/. Check them out!

We also provide a PDF file that has color images of the screenshots/diagrams used in this book. You can download it here: http://www.packtpub.com/sites/default/files/downloads/Bookname_ColorImages.pdf.

There are a number of text conventions used throughout this book.

CodeInText: Indicates code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles. Here is an example: "Mount the downloaded WebStorm-10*.dmg disk image file as another disk in your system."

A block of code is set as follows:

html, body, #map {
 height: 100%; 
 margin: 0;
 padding: 0
}

When we wish to draw your attention to a particular part of a code block, the relevant lines or items are set in bold:

[default]
exten => s,1,Dial(Zap/1|30)
exten => s,2,Voicemail(u100)
exten => s,102,Voicemail(b100)
exten => i,1,Voicemail(s0)

Any command-line input or output is written as follows:

$ mkdir css
$ cd css

Bold: Indicates a new term, an important word, or words that you see on screen. For example, words in menus or dialog boxes appear in the text like this. Here is an example: Select System info from the Administration panel."