Strings & formatted output
- What is a string?
- Unicode basics
- Using fmt package for formatted output
Calling REST APIs
- Making HTTP calls with net/http
- Defining structs
- Serializing JSON
Working with files
- Handling errors
- Using defer to manage resources
- Working with io.Reader & io.Writer interfaces

Code

hw.go - Hello World
- GOOS=drawin go build (also GOARCH)
banner.go - Strings & printing
github.go - Calling REST APIs
sha1.go - Working with io.Reader & io.Writer

Terminal Log

Links

HTTP status cats
errors package (Go 1.13)
encoding/json
net/http
Let's talk about logging by Dave Cheney
Numbers
- math/big - Big numbers
- Numeric types
Strings
- Unicode table
- strings package - string utilities
- Go strings
Annotated "Hello World"
Effective Go - Read this!
Go standard library - official documentation
A Tour of Go
Setting Up
- The Go SDK
- git
- IDE's: Visual Studio Code + Go extension or Goland (paid)

Data & Other

G☺
♡
http.log.gz

Day 2

Agenda

Sorting
- Working with slices
- Writing methods
- Understanding interfaces
Catching panics
- The built-in recover function
- Named return values
Processing text
- Reading line by line with bufio.Scanner
- Using regular expressions
- Working with maps

Code

slices.go - Working with slices
game.go - Structs, methods & interfaces
empty.go - The empty interface, type assertions
div.go - Catching panics
freq.go - Most common word (files, regular expressions, maps)

Terminal Log

Exercises

Read and understand the sort package examples
Implement sortByDistance(players []Player, x, y int) in game.go
Change mostCommon to return the most common n words (e.g. func mostCommon(r io.Reader, n int) ([]string, error))

Links

regex101 - Regular expression builder
Go Proverbs - Think about them ☺
sort examples - Read and try to understand
When to use generics
Generics tutorial
Methods, interfaces & embedded types in Go
Methods & Interfaces in the Go tour
Slices
- Slices & Slice internals on the Go blog
- Slice tricks
Error Handling
- Defer, Panic and Recover
- errors package (Go 1.13)
- pkg/errors

Data & Other

sherlock.txt

Day 3

Agenda

Distributing work
- Using goroutines & channels
- Using the sync package to coordinate work
Timeouts & cancellation
- Working with multiple channels using select
- Using context for timeouts & cancellations
- Standard library support for context

Code

go_chan.go - Goroutines & channels
- sleep_sort.sh - Sleep sort in bash
taxi_check.go - Turn sequential code to parallel
sites_time.go - Using sync.WaitGroup
payment.go - Using sync.Once & sync.WaitGroup
counter.go - Using the race detector, sync.Mutex and sync/atomic
select.go - Using select
rtb.go - Using context for cancellations

Terminal Log

Exercise

In taxi_check.go

Limit the number of goroutines to "n". Which "n" yields the best results?
Cancel all goroutines once there's an error or mismatch in signature

Data & Other

Day 4

Agenda

Testing your code
- Working with the testing package
- Using testify
- Managing dependencies with go mod
Structuring your code
- Writing sub-packages
Writing an HTTP server
- Writing handlers
- Using gorilla/mux for routing Adding metrics & logging
- Using expvar for metrics
- Using the log package and a look at user/zap
Configuration patterns
- Reading environment variables and a look at external packages
- Using the flag package for command line processing

Code

nlp project

├── go.mod - Project & dependencies
├── nlp.go - Package code
├── doc.go - Package level documentation
├── nlp_test.go - Test & benchmark file
├── example_test.go - Testable example
├── stemmer - Sub module
│   ├── stemmer.go
│   └── stemmer_test.go
├── testdata - Test data
│      └── tokenize_cases.toml - Test cases
└── cmd  - Executables
    └── nlpd - HTTP server
        ├── main.go
        └── main_test.go

Terminal Log

Links

Configuration
- envconfig
- viper & cobra
Logging
- Built-in log
- uber/zap
- logrus
- zerolog
Metrics
- Built-in expvar
- Open Telemetry
- Prometheus
Go Code Review Comments
Tutorial: Getting started with multi-module workspaces
Example Project Structure
How to Write Go Code
Documentation
- Godoc: documenting Go code
- Testable examples in Go
- Go documentation tricks
- gob/doc.go of the gob package. Generates this documentation
- go install golang.org/x/pkgsite/cmd/pkgsite@9ffe8b928e4fbd3ff7dcf984254629a47f8b6e63 (require go 1.18)
- pkgsite -http=:8080 (open browser on http://localhost:8080/${module name})
Out Software Dependency Problem - Good read on dependencies by Russ Cox
Linters (static analysis)
- staticcheck
- gosec - Security oriented
- golang.org/x/tools/go/analysis - Helpers to write analysis tools (see example)
Testing
- testing
- testify - Many test utilities (including suites & mocking)
- Tutorial: Getting started with fuzzing
  - testing/quick - Initial fuzzing library
- test containers
HTTP Servers
- net/http
- net/http/httptest
- gorilla/mux - HTTP router with more frills
- chi - A nice web framework

Data & Other

nlp.go
stemmer.go
tokenize_cases.toml
- github.com/BurntSushi/toml