What’s wrong with this m, err := os.Truncate(path,0) if err != nil { log.Printf("Failed to truncate: %v", err) } if I do above I am getting an error like this cannot initialize 2 variables with 1 values while this works without an issue if err := os.Truncate(path, 0); err != nil { log.Printf("Failed to truncate:… Read More cannot initialize 2 variables with 1 values

I am trying to extract the time from a datetime string in golang, here is what I have: func GetTimeStr(d string) string { layout := "2014-09-12T11:45:26" d = d[:len(layout)] t, _ := time.Parse(layout, d) return t.Format("15:04:05") } My input look like this: 2022-09-23T16:28:19.846821Z However I am getting 00:00:00, what am I doing wrong? >Solution :… Read More Golang: extract time from datetime string

Let’s say I have two structs. Point and ColoredPoint. Point is embedded into ColoredPoint. type Point struct { X, Y int } type ColoredPoint struct { R, G, B int Point } func Check(p *ColoredPoint) { if p.Point != nil { // won’t work here. // do something } } I want to check whether… Read More check whether the embedded struct inside a struct is nil?

I need to string scan 23.584950:58.353603:an address, str:a place, name into : type Origin struct { Lat float64 `json:"lat" binding:"required"` Lng float64 `json:"lng" binding:"required"` Address string `json:"address" binding:"required"` Name string `json:"name" binding:"required"` } My code: package main import "fmt" type Origin struct { Lat float64 `json:"lat" binding:"required"` Lng float64 `json:"lng" binding:"required"` Address string `json:"address" binding:"required"`… Read More scanning a string separated by ":" in golang

I’ve written this code for education purposes, now I need to write some test for it. First, I need to test method Worker, but I don’t understand how can I do it properly? I’m totally new to test and to Go generally. package worker import ( "context" "fmt" ) type Queue interface { TakeMessage() (<-chan… Read More How can I test method in proper way in my case?

I’m using the following code: func main() { http.Handle("/", http.FileServer(http.Dir("./web-files"))) http.HandleFunc("/auth/verify", verify) http.HandleFunc("/auth/login", login) http.HandleFunc("/auth/signup", signup) http.ListenAndServe(":8080", nil) } I’m new to go and what I want to do is that every time someone enters my webpage a function named updateCookies runs. I’ve tried to use http.HandleFunc("/", updateCookies) but it didn’t work cause I have… Read More How to run a specific function each time someone enters my website in go?

err := godotenv.Load(".env") if err != nil { panic(err.Error()) } shell := os.Getenv("SHELL") fmt.Println(shell) I set the SHELL=/bin/zsh in my .env file but it seems the os first look for the given key in the os environment variable list and then It checks the .env file . is there a way to separate these two… Read More How to load both .env file and the os environment variables in golang

I’m getting the linting error ineffective assignment to field Player.Level (SA4005)go-staticcheck when I try to use a struct method LevelUp to update the struct’s value Player.Level: func main() { player := Player{ Name: "Tom", Level: 0, } player.LevelUp() fmt.Printf("Player level %d\n", player.Level) } type Player struct { Name string Level int } func (p Player)… Read More Ineffective Assignment to Field when trying to update a Struct in Go

I am going to show a simple compilable code snipped where I get weird behaviour: after I intentionally cause a panic in processData (because I pass nil-pointer) the sending to channel l.done is blocked! package main import ( "context" "fmt" "time" ) type Loop struct { done chan struct{} } type Result struct { ID… Read More Why does sending to channel is blocked when a panic occurs?

I have two questions about the ResponseWriter interface in net/http package. Here is my code package main import ( "fmt" "net/http" "os" ) type handler struct{} func (h *handler) ServeHTTP(w http.ResponseWriter, req *http.Request) { fmt.Fprintf(w, "Method: %v\n", req.Method) fmt.Fprintf(w, "URL: %v\n", req.URL) fmt.Fprintf(w, "Protocol: %v\n", req.Proto) fmt.Fprintf(os.Stdout, "Header: %v\n", w.Header()) } func main() { http.ListenAndServe(":8080",… Read More ResponseWriter interface in Go net/http package