tmrgo1/demo/mycontext/mycontext.go

package main

import (
	"context"
	"fmt"
	"sync"
)

type MyContext struct {
	ctx context.Context
	m sync.Map
}

func (m * MyContext) WithValue(parent MyContext, key, val interface{}) MyContext {
	//ctx := m.WithValue(parent,key,val)
	ctx := new(MyContext)
	ctx.ctx =context.WithValue(parent.ctx,key,val)
	m.m.Store(key,val)
	ctx.m = m.m
	return *ctx
}

func (m * MyContext) Value( key interface{}) interface{}{
	val ,_ :=m.m.Load(key)
	return val
}

func NewMyContext() MyContext{
   mc := MyContext{
	   ctx : context.Background(),
   }
	return mc
}

func main() {
	mc := NewMyContext()

	ctx :=mc.WithValue(mc,"key1","value1")
	ctx1 :=mc.WithValue(ctx,"key2","value2")

	fmt.Println(ctx.Value("key2"),ctx1.Value("key2"))

}