commit 2c75b203496f0812533868c54aae59d87a8b3f00
Author: Levente Batuska <mr.levente97@gmail.com>
Date:   Thu Sep 12 22:16:26 2024 +0200

    inital commit

diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..a8a630b
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,3 @@
+module github.com/lbatuska/goutils
+
+go 1.23.0
diff --git a/logger/ConsoleLogger.go b/logger/ConsoleLogger.go
new file mode 100644
index 0000000..ea8260a
--- /dev/null
+++ b/logger/ConsoleLogger.go
@@ -0,0 +1,71 @@
+package logger
+
+import (
+	"fmt"
+	"time"
+)
+
+func (lgr *ConsoleLoggerimpl) init() {
+	lgr.messages = make(chan string, logbuffersize)
+}
+
+func (logger *ConsoleLoggerimpl) StartLogger() {
+	fmt.Println("Starting Logger")
+	loggerlogonce.Do(func() {
+		for msg := range logger.messages {
+			fmt.Print(msg)
+		}
+	})
+}
+
+func (logger *ConsoleLoggerimpl) Write(message string) {
+	logger.messages <- time.Now().Format(time.UnixDate) + " : " + message + "\n"
+}
+
+func (logger *ConsoleLoggerimpl) Write_Request(message string, uuid string) {
+	logger.Write(uuid + " : " + message)
+}
+
+func (logger *ConsoleLoggerimpl) WriteErr(err error) (errnum int) {
+	if err != nil {
+		logger.Write("Error: " + err.Error())
+		errnum = 1
+	}
+	return errnum
+}
+
+func (logger *ConsoleLoggerimpl) WriteErr_Request(err error, uuid string) (errnum int) {
+	if err != nil {
+		logger.Write(uuid + " : Error: " + err.Error())
+		errnum = 1
+	}
+	return errnum
+}
+
+func (logger *ConsoleLoggerimpl) Write_DEBUG(message string) {
+	if DEBUG {
+		logger.Write(message)
+	}
+}
+
+func (logger *ConsoleLoggerimpl) Write_Request_DEBUG(message string, uuid string) {
+	if DEBUG {
+		logger.Write_Request(message, uuid)
+	}
+}
+
+func (logger *ConsoleLoggerimpl) WriteErr_DEBUG(err error) (errnum int) {
+	if err != nil {
+		logger.Write_DEBUG("Error: " + err.Error())
+		errnum = 1
+	}
+	return errnum
+}
+
+func (logger *ConsoleLoggerimpl) WriteErr_Request_DEBUG(err error, uuid string) (errnum int) {
+	if err != nil {
+		logger.Write_DEBUG(uuid + " : Error: " + err.Error())
+		errnum = 1
+	}
+	return errnum
+}
diff --git a/logger/FileLogger.go b/logger/FileLogger.go
new file mode 100644
index 0000000..f5cb111
--- /dev/null
+++ b/logger/FileLogger.go
@@ -0,0 +1,111 @@
+package logger
+
+import (
+	"fmt"
+	"os"
+	"sync"
+	"time"
+)
+
+func (lgr *FileLoggerimpl) init() {
+	lgr.filepath = "./log"
+	lgr.messages = make(chan string, logbuffersize)
+	envfp, envexist := os.LookupEnv("LOGFILE_GO_LOGGER")
+	if envexist {
+		if len(envfp) > 0 {
+			lgr.filepath = envfp
+		} else {
+			Logger().Write_DEBUG(fmt.Sprintf("LOGFILE_GO_LOGGER env exist but has an empty value using default value: %s !\n", lgr.filepath))
+		}
+	} else {
+		Logger().Write_DEBUG(fmt.Sprintf("LOGFILE_GO_LOGGER env doesn't exist using default value: %s !\n", lgr.filepath))
+	}
+	f, err := os.OpenFile(lgr.filepath, os.O_RDWR|os.O_APPEND|os.O_CREATE, 0660)
+	if err != nil {
+		// We probably really don't want to continue execution without file backed logging
+		panic(fmt.Sprintf("Error opening or creating file: %s", err.Error()))
+	}
+	lgr.logFile = f
+	lgr.mutex = &sync.Mutex{}
+}
+
+func (logger *FileLoggerimpl) StartLogger() {
+	fmt.Println("Starting FileLogger")
+	loggerlogonce.Do(func() {
+		for msg := range logger.messages {
+
+			logger.mutex.Lock()
+			_, err := logger.logFile.WriteString(msg)
+			if err != nil {
+				fmt.Println(err.Error())
+				logger.logFile.Close()
+				logger.mutex.Unlock()
+				panic("Failed to write to file")
+			}
+			err = logger.logFile.Sync()
+			if err != nil {
+				logger.logFile.Close()
+				logger.mutex.Unlock()
+
+				panic("Failed to write to file")
+			}
+			logger.mutex.Unlock()
+		}
+	})
+	// Technically we should do this but this will never run
+	// logger.mutex.Lock()
+	// logger.logFile.Close()
+	// logger.mutex.Unlock()
+}
+
+func (logger *FileLoggerimpl) Write(message string) {
+	logger.messages <- time.Now().Format(time.UnixDate) + " : " + message + "\n"
+}
+
+func (logger *FileLoggerimpl) Write_Request(message string, request string) {
+	logger.Write(request + " : " + message)
+}
+
+func (logger *FileLoggerimpl) WriteErr(err error) (errnum int) {
+	if err != nil {
+		logger.Write("Error: " + err.Error())
+		errnum = 1
+	}
+	return errnum
+}
+
+func (logger *FileLoggerimpl) WriteErr_Request(err error, uuid string) (errnum int) {
+	if err != nil {
+		logger.Write(uuid + " : Error: " + err.Error())
+		errnum = 1
+	}
+	return errnum
+}
+
+func (logger *FileLoggerimpl) Write_DEBUG(message string) {
+	if DEBUG {
+		logger.Write(message)
+	}
+}
+
+func (logger *FileLoggerimpl) Write_Request_DEBUG(message string, uuid string) {
+	if DEBUG {
+		logger.Write_Request(message, uuid)
+	}
+}
+
+func (logger *FileLoggerimpl) WriteErr_DEBUG(err error) (errnum int) {
+	if err != nil {
+		logger.Write_DEBUG("Error: " + err.Error())
+		errnum = 1
+	}
+	return errnum
+}
+
+func (logger *FileLoggerimpl) WriteErr_Request_DEBUG(err error, uuid string) (errnum int) {
+	if err != nil {
+		logger.Write_DEBUG(uuid + " : Error: " + err.Error())
+		errnum = 1
+	}
+	return errnum
+}
diff --git a/logger/Logger.go b/logger/Logger.go
new file mode 100644
index 0000000..4a39501
--- /dev/null
+++ b/logger/Logger.go
@@ -0,0 +1,48 @@
+package logger
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"reflect"
+	"sync"
+)
+
+// Use this in the init() function to initialize the size of the buffered channel
+const logbuffersize int32 = 200
+
+var DEBUG bool = true
+
+var (
+	loggerInstance LGRImpl
+	loggeronce     sync.Once
+	loggerlogonce  sync.Once
+)
+
+func Create(instance LGRImpl) {
+	loggeronce.Do(func() {
+		loggerInstance = instance
+		loggerInstance.init()
+	})
+}
+
+func Logger() LGRImpl {
+	return loggerInstance
+}
+
+func PrintJson[T any](entity *T) string {
+	typename := reflect.TypeFor[T]().Name()
+	outputStringJson, err := json.MarshalIndent((*entity), "", "     ")
+	if err != nil {
+		return "Error parsing json data"
+	} else {
+		return typename + ":\n" + string(outputStringJson) + "\n"
+	}
+}
+
+func ExampleLogMiddleware(next http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		Logger().Write_DEBUG(fmt.Sprintf("\tRequest from: %s to: Host: %s URL: %s \tWith HEADERS: %s \tWith BODY: %s", r.RemoteAddr, r.Host, r.URL, r.Header, r.Body))
+		next.ServeHTTP(w, r)
+	})
+}
diff --git a/logger/NullLogger.go b/logger/NullLogger.go
new file mode 100644
index 0000000..6d0e125
--- /dev/null
+++ b/logger/NullLogger.go
@@ -0,0 +1,41 @@
+package logger
+
+func (lgr *NullLoggerimpl) init() {}
+
+func (logger *NullLoggerimpl) StartLogger() {}
+
+func (logger *NullLoggerimpl) Write(message string) {}
+
+func (logger *NullLoggerimpl) Write_Request(message string, request string) {}
+
+func (logger *NullLoggerimpl) WriteErr(err error) (errnum int) {
+	if err != nil {
+		errnum = 1
+	}
+	return errnum
+}
+
+func (logger *NullLoggerimpl) WriteErr_Request(err error, request string) (errnum int) {
+	if err != nil {
+		errnum = 1
+	}
+	return errnum
+}
+
+func (logger *NullLoggerimpl) Write_DEBUG(message string) {}
+
+func (logger *NullLoggerimpl) Write_Request_DEBUG(message string, uuid string) {}
+
+func (logger *NullLoggerimpl) WriteErr_DEBUG(err error) (errnum int) {
+	if err != nil {
+		errnum = 1
+	}
+	return errnum
+}
+
+func (logger *NullLoggerimpl) WriteErr_Request_DEBUG(err error, uuid string) (errnum int) {
+	if err != nil {
+		errnum = 1
+	}
+	return errnum
+}
diff --git a/logger/interfaces.go b/logger/interfaces.go
new file mode 100644
index 0000000..aa4bb56
--- /dev/null
+++ b/logger/interfaces.go
@@ -0,0 +1,47 @@
+package logger
+
+// Message format(s)
+//
+// Unixdate : message\n
+//
+// Unixdate : Error: error\n
+//
+// Unixdate : uuid : message\n
+//
+// Unixdate : uuid : Error: error\n
+type LGRImpl interface {
+	LoggerI
+	DebugLoggerI
+}
+
+type (
+	LoggerI interface {
+		// Private, use it for member initialization etc
+		init()
+		// Start an infinite loop to write out messages from the channel
+		StartLogger()
+		Write(message string)
+		Write_Request(message string, uuid string)
+		// If an error that is not nill passed in it logs the error and returns 1, otherwise 0
+		WriteErr(error) int
+		WriteErr_Request(err error, uuid string) int
+	}
+	// Use _DEBUG prints to strip them out of release builds
+	DebugLoggerI interface {
+		// Private, use it for member initialization etc
+		init()
+		// Start an infinite loop to write out messages from the channel
+		StartLogger()
+		Write_DEBUG(message string)
+		Write_Request_DEBUG(message string, uuid string)
+		WriteErr_DEBUG(err error) (errnum int)
+		WriteErr_Request_DEBUG(err error, uuid string) int
+	}
+)
+
+// Ensure all methods from LGRImpl are implemented ccompile time
+var (
+	_ LGRImpl = (*NullLoggerimpl)(nil)
+	_ LGRImpl = (*ConsoleLoggerimpl)(nil)
+	_ LGRImpl = (*FileLoggerimpl)(nil)
+)
diff --git a/logger/types.go b/logger/types.go
new file mode 100644
index 0000000..f8ea9ac
--- /dev/null
+++ b/logger/types.go
@@ -0,0 +1,21 @@
+package logger
+
+import (
+	"os"
+	"sync"
+)
+
+// A logger without logging functionality
+type NullLoggerimpl struct{}
+
+// A logger that logs to sdtout
+type ConsoleLoggerimpl struct {
+	messages chan string
+}
+
+type FileLoggerimpl struct {
+	messages chan string
+	mutex    *sync.Mutex
+	logFile  *os.File
+	filepath string
+}
diff --git a/main_test.go b/main_test.go
new file mode 100644
index 0000000..cf00beb
--- /dev/null
+++ b/main_test.go
@@ -0,0 +1,36 @@
+package main
+
+import (
+	"errors"
+	"testing"
+	"time"
+
+	. "github.com/lbatuska/goutils/logger"
+	. "github.com/lbatuska/goutils/testing"
+	. "github.com/lbatuska/goutils/typeutils"
+)
+
+func TestTypes(t *testing.T) {
+	Create(&FileLoggerimpl{})
+	go Logger().StartLogger()
+	Logger().Write("TEST MSG")
+	time.Sleep(time.Second * 2)
+	x := Some("Test")
+	AssertTrue(t, x.Is_some())
+	AssertTrue(t, !x.Is_none())
+	AssertEqual(t, x.Unwrap(), "Test")
+	AssertTrue(t, None_t(1).Is_none())
+	err := errors.New("Test")
+	y := Err_t(err, "t")
+	AssertEqual(t, y.Unwrap_err(), err)
+	AssertError(t, y.Unwrap_err())
+	z := x.Ok_or(err)
+	AssertTrue(t, z.Is_ok())
+	AssertEqual(t, None[string]().Ok_or(err).Unwrap_err(), err)
+	AssertTrue(t, Has_value(x))
+	AssertTrue(t, Has_value(y.Err()))
+	AssertTrue(t, Has_value(y.Err().Ok_or(err)))
+	AssertEqual(t, err, y.Err().Ok_or(err).Unwrap())
+	AssertEqual(t, err, y.Err().Ok_or(errors.New("")).Unwrap())
+	AssertNotEqual(t, err, Err[string](errors.New("asd")).Unwrap_err())
+}
diff --git a/testing/testing.go b/testing/testing.go
new file mode 100644
index 0000000..bd1adea
--- /dev/null
+++ b/testing/testing.go
@@ -0,0 +1,25 @@
+package testing
+
+import "testing"
+
+func AssertEqual[T comparable](t *testing.T, expected T, actual T) {
+	t.Helper()
+	if expected == actual {
+		t.Logf("✅ [%T](%+v) == [%T](%+v)", expected, expected, actual, actual)
+		return
+	}
+	t.Errorf("❌ [%T](%+v) != [%T](%+v)", expected, expected, actual, actual)
+}
+
+func AssertNotEqual[T comparable](t *testing.T, expected T, actual T) {
+	t.Helper()
+	if expected != actual {
+		t.Logf("✅ [%T](%+v) != [%T](%+v)", expected, expected, actual, actual)
+		return
+	}
+	t.Errorf("❌ [%T](%+v) == [%T](%+v)", expected, expected, actual, actual)
+}
+
+func AssertTrue(t *testing.T, expected bool) { AssertEqual(t, true, expected) }
+
+func AssertError(t *testing.T, expected error) { AssertTrue(t, expected != nil) }
diff --git a/typeutils/interfaces.go b/typeutils/interfaces.go
new file mode 100644
index 0000000..d8cd06f
--- /dev/null
+++ b/typeutils/interfaces.go
@@ -0,0 +1,43 @@
+package typeutils
+
+// Created to abstract over Is_some and Is_ok
+type ValueContainer interface {
+	Has_value() bool
+}
+
+type Unwrappable[T any] interface {
+	Expect(string) T           // panics with a provided custom message
+	Unwrap() T                 // panics with a generic message
+	Unwrap_or(T) T             // returns the provided default value
+	Unwrap_or_default() T      // returns the default value of the type T
+	Unwrap_or_else(func() T) T // returns the result of evaluating the provided function
+}
+
+// Both an Optional and Result is an Option
+type Option[T any] interface {
+	Unwrappable[T]
+}
+
+type OptionalI[T any] interface {
+	Is_some() bool
+	Is_none() bool
+	Ok_or(error) Result[T]
+	Ok_or_else(func() error) Result[T]
+}
+
+type ResultI[T any] interface {
+	Is_ok() bool
+	Is_err() bool
+	Ok() Optional[T]
+	Err() Optional[error]
+}
+
+// Ensure compile time the interfaces are implemented
+var (
+	_ Option[any]    = (*Optional[any])(nil)
+	_ Option[any]    = (*Result[any])(nil)
+	_ OptionalI[any] = (*Optional[any])(nil)
+	_ ResultI[any]   = (*Result[any])(nil)
+	_ ValueContainer = (*Optional[any])(nil)
+	_ ValueContainer = (*Result[any])(nil)
+)
diff --git a/typeutils/optional.go b/typeutils/optional.go
new file mode 100644
index 0000000..60ee9d9
--- /dev/null
+++ b/typeutils/optional.go
@@ -0,0 +1,77 @@
+package typeutils
+
+// CTORS BEGIN
+func Some[T any](value T) Optional[T] {
+	return Optional[T]{value, true}
+}
+
+func None[T any]() Optional[T] {
+	return Optional[T]{present: false}
+}
+
+// Because None has no type passing a value of desired type might be preferred syntax over providing type on the function call
+func None_t[T any](T) Optional[T] {
+	return Optional[T]{present: false}
+}
+
+// CTORS END
+
+func (opt Optional[T]) Is_some() bool { return opt.present }
+func (opt Optional[T]) Is_none() bool { return !opt.present }
+
+func (opt Optional[T]) Has_value() bool { return opt.Is_some() }
+
+// UNWRAPPABLE INTERFACE BEGIN
+func (opt Optional[T]) Expect(msg string) T {
+	if opt.present {
+		return opt.value
+	}
+	panic(msg)
+}
+
+func (opt Optional[T]) Unwrap() T {
+	if opt.present {
+		return opt.value
+	}
+	panic("Tried unwrapping an Optional that did not have a value!")
+}
+
+func (opt Optional[T]) Unwrap_or(val T) T {
+	if opt.present {
+		return opt.value
+	}
+	return val
+}
+
+func (opt Optional[T]) Unwrap_or_default() T {
+	if opt.present {
+		return opt.value
+	}
+	var res T
+	return res
+}
+
+func (opt Optional[T]) Unwrap_or_else(f func() T) T {
+	if opt.present {
+		return opt.value
+	}
+	return f()
+}
+
+// UNWRAPPABLE INTERFACE END
+
+// transforms Some(v) to Ok(v), and None to Err(err)
+func (opt Optional[T]) Ok_or(err error) Result[T] {
+	if opt.present {
+		return Ok(opt.value)
+	}
+	return Err[T](err)
+}
+
+// transforms Some(v) to Ok(v), and None to a value of Err using the provided function
+func (opt Optional[T]) Ok_or_else(f func() error) Result[T] {
+	if opt.present {
+		return Ok(opt.value)
+	}
+	return Err[T](f())
+}
diff --git a/typeutils/result.go b/typeutils/result.go
new file mode 100644
index 0000000..8365abd
--- /dev/null
+++ b/typeutils/result.go
@@ -0,0 +1,92 @@
+package typeutils
+
+// CTORS BEGIN
+func Ok[T any](value T) Result[T] {
+	return Result[T]{value: value, err: nil}
+}
+
+func Err[T any](err error) Result[T] {
+	return Result[T]{err: err}
+}
+
+func Err_t[T any](err error, x T) Result[T] {
+	return Result[T]{err: err}
+}
+
+// CTORS END
+
+func (res Result[T]) Is_ok() bool  { return res.err == nil }
+func (res Result[T]) Is_err() bool { return res.err != nil }
+
+func (res Result[T]) Has_value() bool { return res.Is_ok() }
+
+// UNWRAPPABLE INTERFACE
+func (res Result[T]) Expect(msg string) T {
+	if res.err == nil {
+		return res.value
+	}
+	panic(msg)
+}
+
+func (res Result[T]) Unwrap() T {
+	if res.err == nil {
+		return res.value
+	}
+	panic("Tried unwrapping a Result that had an error a value!")
+}
+
+func (res Result[T]) Unwrap_or(val T) T {
+	if res.err == nil {
+		return res.value
+	}
+	return val
+}
+
+func (res Result[T]) Unwrap_or_default() T {
+	if res.err == nil {
+		return res.value
+	}
+	var ret T
+	return ret
+}
+
+func (res Result[T]) Unwrap_or_else(f func() T) T {
+	if res.err == nil {
+		return res.value
+	}
+	return f()
+}
+
+// UNWRAPPABLE INTERFACE
+
+// This function panic on Ok instead of Err
+func (res Result[T]) Expect_err(msg string) error {
+	if res.err != nil {
+		return res.err
+	}
+	panic(msg)
+}
+
+// This function panic on Ok instead of Err
+func (res Result[T]) Unwrap_err() error {
+	if res.err != nil {
+		return res.err
+	}
+	panic("Expect_err was called with an Ok value")
+}
+
+// transforms Result into Option, mapping Ok(v) to Some(v) and Err(e) to None
+func (res Result[T]) Ok() Optional[T] {
+	if res.err == nil {
+		return Optional[T]{value: res.value, present: true}
+	}
+	return Optional[T]{present: false}
+}
+
+// transforms Result into Option, mapping Err(e) to Some(e) and Ok(v) to None
+func (res Result[T]) Err() Optional[error] {
+	if res.err != nil {
+		return Optional[error]{value: res.err, present: true}
+	}
+	return Optional[error]{present: false}
+}
diff --git a/typeutils/types.go b/typeutils/types.go
new file mode 100644
index 0000000..9dfde38
--- /dev/null
+++ b/typeutils/types.go
@@ -0,0 +1,11 @@
+package typeutils
+
+type Optional[T any] struct {
+	value   T
+	present bool
+}
+
+type Result[T any] struct {
+	value T
+	err   error
+}
diff --git a/typeutils/utils.go b/typeutils/utils.go
new file mode 100644
index 0000000..e7aeed8
--- /dev/null
+++ b/typeutils/utils.go
@@ -0,0 +1,27 @@
+package typeutils
+
+func Expect[T any](val Unwrappable[T], msg string) T {
+	return val.Expect(msg)
+}
+
+func Unwrap[T any](val Unwrappable[T]) T {
+	return val.Unwrap()
+}
+
+func Unwrap_or[T any](val Unwrappable[T]) (def T) {
+	return val.Unwrap_or(def)
+}
+
+func Unwrap_or_default[T any](val Unwrappable[T]) T {
+	return val.Unwrap_or_default()
+}
+
+func Unwrap_or_else[T any](val Unwrappable[T], f func() T) T {
+	return val.Unwrap_or_else(f)
+}
+
+// T cannot be inferred
+// Returns if the underlying data has a Value (false in case of None or Error)
+func Has_value(val ValueContainer) bool {
+	return val.Has_value()
+}