Go Programming Language For Dummies

 Title Page....3 Copyright Page....4 Table of Contents....7 Introduction....13 About This Book....13 Foolish Assumptions....14 Icons Used in This Book....14 Beyond the Book....15 Where to Go from Here....15 Part 1 Getting Started with Go....17 Chapter 1 Hello, Go!....19 Seeing What Learning Go Can Do for You....20 Installing Go on Your Machine....21 macOS....22 Windows....23 Using an Integrated Development Environment with Go....24 Writing Your First Go Program....26 Compiling and running the program....27 Understanding how a Go program works....29 Making sense of the Go file structure....30 Compiling for multiple operating systems....31 Comparing Go with Other Languages....33 Syntax....33 Compilation....34 Concurrency....34 Library support....34 Chapter 2 Working with Different Data Types....35 Declaring Always-Changing Variables....36 Using the var keyword: Type-inferred variables....36 Specifying the data type: Explicitly typed variables....37 Using the short variable declaration operator....38 Declaring Never-Changing Constants....39 Removing Unused Variables....39 Dealing with Strings....41 Performing Type Conversions....42 Discovering the type of a variable....43 Converting a variable’s type....44 Interpolating strings....46 Chapter 3 Making Decisions....49 Using If/Else Statements to Make Decisions....49 Laying the foundation for the if/else statement: Logical and comparison operators....50 Using the if/else statement....52 Short-circuiting: Evaluating conditions in Go....54 When You Have Too Many Conditions: Using the Switch Statement....58 Switching with fall-throughs....59 Matching multiple cases....60 Switching without condition....60 Chapter 4 Over and Over and Over: Using Loops....63 Performing Loops Using the for Statement....63 Iterating over a Range of Values....68 Iterating through arrays/slices....68 Iterating through a string....70 Using Labels with the for Loop....71 Chapter 5 Grouping Code into Functions....77 Defining a Function....77 Defining functions with parameters....78 Defining functions with multiple parameters....80 Passing arguments by value and by pointer....80 Returning values from functions....83 Naming return values....84 Working with variadic functions....84 Using Anonymous Functions....85 Declaring an anonymous function....85 Implementing closure using anonymous functions....86 Implementing the filter() function using closure....88 Part 2 Working with Data Structures....91 Chapter 6 Slicing and Dicing Using Arrays and Slices....93 Arming Yourself to Use Arrays....93 Declaring an array....94 Initializing an array....95 Working with multidimensional arrays....95 Sleuthing Out the Secrets of Slices....98 Creating an empty slice....98 Creating and initializing a slice....100 Appending to a slice....100 Slicing and Ranging....104 Extracting part of an array or slice....104 Iterating through a slice....107 Making copies of an array or slice....107 Inserting an item into a slice....109 Removing an item from a slice....111 Chapter 7 Defining the Blueprints of Your Data Using Structs....113 Defining Structs for a Collection of Items....113 Creating a Go Struct....116 Making a Copy of a Struct....117 Defining Methods in Structs....119 Comparing Structs....122 Chapter 8 Establishing Relationships Using Maps....125 Creating Maps in Go....125 Initializing a map with a map literal....127 Checking the existence of a key....127 Deleting a key....128 Getting the number of items in a map....128 Iterating over a map....129 Getting all the keys in a map....129 Setting the iteration order in a map....130 Sorting the items in a map by values....130 Using Structs and Maps in Go....133 Creating a map of structs....133 Sorting a map of structs....136 Chapter 9 Encoding and Decoding Data Using JSON....141 Getting Acquainted with JSON....141 Object....142 String....142 Boolean....143 Number....143 Object....144 Array....144 null....145 Decoding JSON....146 Decoding JSON to a struct....147 Decoding JSON to arrays....148 Decoding embedded objects....149 Mapping custom attribute names....152 Mapping unstructured data....153 Encoding JSON....156 Encoding structs to JSON....156 Encoding interfaces to JSON....160 Chapter 10 Defining Method Signatures Using Interfaces....163 Working with Interfaces in Go....164 Defining an interface....164 Implementing an interface....165 Looking at How You May Use Interfaces....166 Adding methods to a type that doesn’t satisfy an interface....170 Using the Stringer interface....171 Implementing multiple interfaces....172 Using an empty interface....173 Determining whether a value implements a specific interface....174 Part 3 Multitasking in Go....175 Chapter 11 Threading Using Goroutines....177 Understanding Goroutines....178 Using Goroutines with Shared Resources....180 Seeing how shared resources impact goroutines....180 Accessing shared resources using mutual exclusion....183 Using atomic counters for modifying shared resources....184 Synchronizing Goroutines....186 Chapter 12 Communicating between Goroutines Using Channels....191 Understanding Channels....191 How channels work....192 How channels are used....195 Iterating through Channels....198 Asynchronously Waiting on Channels....199 Using Buffered Channels....204 Part 4 Organizing Your Code....207 Chapter 13 Using and Creating Packages in Go....209 Working with Packages....209 Creating shareable packages....212 Organizing packages using directories....214 Using Third-Party Packages....216 Emojis for Go....216 Go Documentation....217 Chapter 14 Grouping Packages into Modules....223 Creating a Module....223 Testing and Building a Module....226 Publishing a Module on GitHub....228 Part 5 Seeing Go in Action....235 Chapter 15 Consuming Web APIs Using Go....237 Understanding Web APIs....237 Fetching Data from Web Services in Go....238 Writing a Go program to connect to a web API....239 Decoding JSON data....241 Refactoring the code for decoding JSON data....245 Fetching from multiple web services at the same time....250 Returning Goroutine’s results to the main() function....251 Chapter 16 Getting Ready to Serve Using REST APIs....255 Building Web Services Using REST APIs....255 HTTP messages....256 REST URLs....256 REST methods....258 REST response....260 Creating a REST API in Go....261 Getting your REST API up and running....261 Testing the REST API....263 Registering additional paths....263 Passing in query string....266 Specifying request methods....267 Storing the course information on the REST API....269 Testing the REST API again....279 Chapter 17 Working with Databases....283 Setting Up a MySQL Database Server....284 Interfacing with the MySQL server....284 Creating a database and table....286 Creating a new account and granting permission....287 Connecting to the MySQL Database in Go....288 Retrieving a record....290 Adding a record....292 Modifying a record....293 Deleting a record....295 Part 6 The Part of Tens....297 Chapter 18 Ten Useful Go Packages to Create Applications....299 color....299 Installation....300 Code sample....300 now....300 Installation....300 Code sample....300 go-pushbullet....301 Installation....301 Code sample....301 goid....302 Installation....302 Code sample....302 json2go....303 Installation....303 Code sample....303 gojq....304 Installation....305 Code sample....305 turtle....306 Installation....306 Code sample....306 go-http-client....307 Installation....307 Code sample....307 notify....308 Installation....308 Code sample....308 gosx-notifier....309 Installation....309 Code sample....309 Chapter 19 Ten Great Go Resources....311 The Official Go Website....311 Go by Example....312 A Tour of Go....312 The Go Frequently Asked Questions....312 The Go Playground....312 Go Bootcamp....313 Effective Go....313 Gophercises....313 Tutorialspoint....313 Stack Overflow....314 Index....315 EULA....339