Repo for basic tutorial-based Golang study

• web crawler with colly
• smth with Hanoi tower
• finish book
• fix web_app_bis (if no JSON is provided, some routes crash)
• init book
• clean issues section (for now)
• fix github actions
• get book "Język Go. Tworzenie idiomatycznego kodu w praktyce" example link other link
• finish web_app_bis tutorial (mostly done, need to check if everything works OK)

• cd app_name
• go build -v ./
• go test -v ./
• go run main.go

booking app tutorial (booking app + some basics)
basics tutorial (most basics)
web app tutorial (web app + Gin)
web app bis tutorial (web app + Gin)

• How should modules / packages be organized? How are they organized in real-life large projects? docs
• How specifically, does hash maps work in Golang?
• (DONE) func (u *UserService) CreateUser(user *models.User) What does the (u *UserService) part mean? Likely, it specifies return type, it so? (CreateUser(user *models.User) part specifies the return type)
• (DONE) func (u *UserService) CreateUser(user *models.User) What does * mean? It looks like a pointer... (yep, it's a pointer)
• (DONE) if err := ctx.ShouldBindJSON(&user); err != nil {...} What about ShouldBindJSON? (the syntax means, that we first create err variable, assign value to it and only then check if function returned any errors)
• (DONE) query := bson.D{bson.E{Key: "name", Value: name}} What is bson.D or bson.E? (these are two out of four basic types of BSON documents, which are the basic unit of data in MongoDB, ref: https://www.mongodb.com/docs/drivers/go/current/fundamentals/bson/)

• update := bson.D{primitive.E{Key: "$set", Value: bson.D{
    	primitive.E{Key: "name", Value: user.Name}, 
    	primitive.E{Key: "age", Value: user.Age}, 
    	primitive.E{Key: "address", Value: user.Address},
    }}}
  

  Why changging Bson.E -> primitive.E fixed erorrs ?? (from https://pkg.go.dev/go.mongodb.org/mongo-driver/bson:
  M - unordered representation of a BSON document
  D - ordered representation of a BSON document
  E - a BSON element for a D
  )
• (DONE) difference between = and := in Golang? (:= means 'declare and assign', while = means 'assign')
• (DONE) can you return empty values in Golang? (yes, you can return empty values in Golang, in fact it's quite often a prefered way of doing things - so return nil or just return and don't bother)

• golang function syntax:
  func functionName(parameter1 type1, parameter2 type2, parameterN typeN) returnType { //function body }

• most important basics
  • Go cheatsheet
  • Google style guide for Golang
  • language specification
• pointers, performance
  • stacks and pointers in Go
  • pointers efficiency
• on type parameters
  • Go 1.18 reease notes
  • 2013 rejected proposal
  • 2021 accepted proposal
  • summary of discussion
• frameworks
  • top 5 frameworks geeksforgeeks
  • web frameworks medium
  • another post on cool, best, can't miss frameworks
• gin
  • gin framework blogpost
  • gin tutorial yt
  • git tutorial yt
  • another gin tutorial yt
  • example REST API using gin
  • another example REST API using gin
• colly
  • github examples
  • some tutorial
  • save data to csv after scrapping
• misc
  • blogpost on bulldogjob
  • official docker image
  • Athens alternative package sever
  • arxiv paper on usage of 'unsafe'
  • effective go
  • A* implementation in Go