Go Mastery: The Definitive Golang Guide

Master Go variables and constants in a statically typed language, including var versus short declarations, types like string and int, and package versus function level usage.

Define custom types in Go to give semantic meaning to data, such as username as string. Use var and short declarations to create variables of these types, keeping code clear.

Master Go functions as reusable, modular blocks that accept parameters and return outputs, using the func keyword. Build and test a divide function with error handling for a zero divisor.

Learn to store multiple values in Go with arrays and slices, compare fixed-size arrays to dynamic slices, and loop with for and range to print and append items.

Explore maps as unordered key-value collections in Go, showing how to define maps with the map keyword and how to add, update, and delete entries.

Explore building a movie matcher app in Go Mastery, using structs, interfaces, and pointers; implement user creation, a recommendation engine, print user details, and save results to a file.

Define and use Go structs for user and movie, with a custom category type, populate fields, iterate with range to print details, and demonstrate handling unused variables.

learn to implement the createUser function in Go by returning a user struct with a name and a list of preferred movie categories, and use it in main.

Implement a Go recommend function that takes a user and a movie slice, filters by the user's categories, and returns suggested movies; build the core of a recommendation engine.

Learn to implement robust error handling in Go by returning (value, error), using errors.New for no matching movies, and handling nil errors in the main flow of a recommendation engine.

Implement a print user detail method on the user object that outputs the user name and preferred categories. Handle command errors and print the user detail, including recommended movies.

Learn how pointers enable updating the original struct by passing a reference instead of by value; practice using ampersand to take an address and asterisks to dereference in Go.

Explores interfaces in Go, showing how square and triangle satisfy the shape interface by implementing a get area method returning a float, enabling polymorphic area printing via print area function.

Apply Go style by defining a recommender interface to decouple movie recommendations from data and enable swapping algorithms with a category recommender.

Learn how to save a user's details to a local file in Go. Format data with fmt, convert to a byte slice, write via the os package, and handle errors.

Celebrate completing the immature project and mastering variables, structs, slices, maps, and interface pointers in Go. Prepare to build clis and web servers.

Master writing a unit test in Go with the built in testing framework in the same package; place the _test.go file, define TestAdd(t *testing.T), and run go test.

Create a TestRecommend test in a main_test.go to validate the recommend function with a category recommender and user, using go test, checking for errors and at least one recommendation.

Test the no-matches edge case in the recommendation function, verifying that a user with preferences receives an error or an empty list when no movies match (e.g., horror).

Build a simple sequential url checker in Go using the http package and http.Get to determine if each url is up or down, preparing for the next lecture on concurrency.

Explore goroutines, Go's lightweight concurrency threads, and how the go keyword launches URL checks, while the main function waits with a time.sleep hack and introduces a wait group for synchronization.

Leverage goroutines and the sync wait group to replace sleep with a wait, add each check, and wait for all URL checks to finish.

Learn to coordinate goroutines with wait groups and enable inter-goroutine communication using channels, sending and receiving strings between the main and child goroutines.

Utilize buffered channels in Go to allow non-blocking sends and smooth inter-goroutine communication, boosting performance and scalability by buffering messages such as urls and preventing blocking.

Learn to build go cli apps with cobra, defining root and subcommands, using flags, and implementing a log filter that reads and filters logs by level and keyword.

Learn to build a log filter cli with cobra by creating the root command as program entry point, initializing a go module, and wiring run logic to print log lines.

go mastery: the definitive golang guide introduces adding a filter subcommand to the root cobra command, with flags for file, level, and keyword to filter logs.

Go mastery teaches building a command-line log reader by implementing a readline function that streams log lines with a memory-efficient buffer and returns lines and errors.

Build a Go CLI to read a log file, filter lines by level and keyword, and print matching entries with a Cobra-based, case-insensitive filter.

Build a Go binary with go build, name it log filter, run the executable, and use the filter subcommand with log file, level error, and keyword db to show matches.