Essential Go

Getting started
- Windows install and setup
- Mac OS install and setup
- Linux install and setup
- Hello, World!
- Take a guided tour
- Access documentation offline
- Run Go in online playground
- GOPATH, GOROOT, GOBIN
Basic types
- Booleans
- Integers
- Floating-point numbers
- Characters and runes
- Strings
- Constants
- Enums
- Arrays
- Slices
- Maps
- Structs
- Interfaces
- Empty interface
- Pointers
- Unions
- Channels
- Zero values
- Type casting
- Type aliases
Variables
- Basic variable declaration
- Multiple variable assignment
- Blank identifier
Constants
- Typed vs. untyped constants
- iota
- Emulating enums
Strings
- Find string in another string
- Compare strings
- Convert to lower case or upper case
- Convert to int, float
- Trim strings (remove chars or substrings)
- Replace text in strings
- Split and join strings
- Format text
- Parse text
- Read file line by line
- Normalize newlines
Pointers
- Basics of pointers
- Dereferencing pointers
- Pointer vs. value methods
Arrays
- Create array
- Array indexes
- Multidimensional array
Slices
- Create a slice
- Length and capacity
- Append to slice
- Filter a slice
- Remove elements from slice
- Duplicate a slice
- Zero value of slice
- Slice tricks
- Optimize by pre-allocating slice
Maps
- Declare and initialize a map
- Create a map
- Get value by key
- Get map size (number of map entries)
- Copy a map
- Iterate a map with range
- Delete from a map
- Use map as a set
- Maps with slices as values
- Concurrent access of maps
- Zero value of a map
Structs
- Basic declaration
- Struct literals
- Anonymous structs
- Composition and embedding
- Exported vs. unexported fields (private vs public)
- Struct tags
- Duplicate a struct (make a copy)
- Empty struct
- Methods
Interfaces
- Simple interface
- Determining underlying type from interface
- Ensure that type implements interface
Empty interface
if, switch, goto
- if statement
- switch statement
- goto statements
for, while loops
- Different forms of for loop
- break and continue
- while loop
range statement
- range over a string
- range over a slice
- range over a map
- range over a channel
Functions
- Variables of function type
- Closures
Methods
Error handling
- Returning an error
- Creating standard error values
- Custom error types
- Handling an error
- Handling errors in short programs
- Add callstack to error messages
- Writing good error messages
Defer
- Defer in depth
- Defer pitfalls
Panic and recover
- Panic
- Recover
- Recovering from panic
- Use cases for panic
Concurrency
- Hello World goroutine
- Create goroutines
- Wait for goroutines to finish
- Limiting concurrency with a semaphore
Channels and select
- Using range to read from a channel
- Timeout reading from a channel with select
- Closing channels
- Buffered vs. unbuffered channels
- Non-blocking receive with select
- Signaling channel with chan struct{}
- Checking if channel has data available
- Channel idioms
Mutex
- Read-Write mutes (RWMutex)
- Mutex gotchas
- Detecting races
Packages
- Installing packages locally with go get
- Importing packages
- Creating a package
- Package initialization
- Package naming best practices
Files and I/O
- Reading files
- Writing files
- File operations
- Directory operations
- File path operations
- I/O related interfaces
Time and date
- Format time
- Parse time
- Format time like strftime
- Compare time and date
Command line arguments
- Access raw command line arguments
- Libraries for advanced parsing of command-line arguments
Logging
- Logging libraries
Executing commands
- Timing out process execution
- os.Exec pitfalls
Hex, base64 encoding
JSON
- Parsing arbitrary JSON documents
- Decoding into anonymous structs
- Decoding JSON from a file
- Configuring JSON serialization
- Custom JSON marshaling
- Go to JSON type mappings
- Easy generation of JSON struct definition
XML
- Pull (streaming) XML parsing
- Hybrid XML parsing: combine pull and unmarshal
- Parse XML from file
- Configuring XML parsing and serialization
- Custom XML marshaling
- Easy generation of XML struct definition
CSV
- Configuring CSV parsing and writing
YAML
SQL
- Querying
- MySQL
- Opening a database
HTTP Client
- HTTP POST
- PUT request of JSON object
- Timeout requests with a context
- GET with URL parameters and a JSON response
- Set User-Agent
- ways of doing HTTP requests
HTTP Server
- Hello World
- Create a HTTPS Server
- HTTP Hello World with custom server and mux
- Responding to an HTTP Request using Templates
- Serving content using ServeMux
- Using a handler function
- Handling http method, accessing query strings & request body
Text and HTML templates
- Methods as data
- if action
- range action
- Built-in functions
- Custom functions
- HTML templates
Reflection
- Primitive types
- Pointers
- Structs
- Slice
- reflect.Kind
- Uses for reflection
Context
- Context with value
- Writing cancellable functions
- Context is a tree of values
- context.TODO() vs. context.Background()
Package fmt
- Basic fmt
- Stringer interface
OS Signals
Testing
- Basic Test
- Table-driven unit tests
- Testing using setUp and tearDown function
- Benchmarks
- Example tests (self documenting tests)
- Testing HTTP requests
- Set/Reset mock function in tests
- View code coverage in HTML format
Calling C from GO with cgo
- Cgo: First steps tutorial
- Calling C Function From Go
- Wire C and Go code in all directions
Profiling using go tool pprof
- Basic cpu and memory profiling
- Using Benchmarks to Create Profile
- Basic memory profiling
- Set CPU/Block profile rate
- Accessing Profile File
Cross compilation
Conditional compilation with build tags
- Separate integration tests
- Optimized implementations for specific architectures
- Dev vs. production builds
Inlining functions
sync.Pool for better performance
gob
Plugin
- Defining and using a plugin
HTTP server middleware
- Normal Handler Function
- Middleware Calculate time required for handlerFunc to execute
- CORS Middleware
- Auth Middleware
- Recovery Handler to prevent server from crashing
Protobuf in Go
- Using Protobuf with Go
Console I/O
Cryptography
- Encryption and decryption with AES GCM
JWT Authorization
- Parsing and validating a token using the HMAC signing method
- Creating a token using a custom claims type
- Creating, signing, and encoding a JWT token using the HMAC signing method
- Parsing the error types using bitfield checks
- Getting token from HTTP Authorization header
- Using the StandardClaims type by itself to parse a token
Images (PNG, JPEG, BMP, TIFF, WEBP, VP8, GIF)
- Basic concepts
- Loading and saving image
- Cropping image
- Convert color image to grayscale
- Resizing images
The Go Command
- go fmt
- go run
- go build
- go clean
- go get
- go env
- go test
Testing code with CI services
- Test Go code with GitHub actions
Windows GUI programming
- A first window app
Contributors

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