Although it is possible to do this with channels,
I would prefer a hash (map) that is protected by a mutex,
since it is easier in this case.
To give you an idea and get you going:
package main
import (
"fmt"
"net/http"
"sync"
)
type state struct {
*sync.Mutex // inherits locking methods
Vals map[string]string // map ids to values
}
var State = &state{&sync.Mutex{}, map[string]string{}}
func get(rw http.ResponseWriter, req *http.Request) {
State.Lock()
defer State.Unlock() // ensure the lock is removed after leaving the the function
id := req.URL.Query().Get("id") // if you need other types, take a look at strconv package
val := State.Vals[id]
delete(State.Vals, id)
rw.Write([]byte("got: " + val))
}
func post(rw http.ResponseWriter, req *http.Request) {
State.Lock()
defer State.Unlock()
id := req.FormValue("id")
State.Vals[id] = req.FormValue("val")
rw.Write([]byte("go to http://localhost:8080/?id=42"))
}
var form = `<html>
<body>
<form action="/" method="POST">
ID: <input name="id" value="42" /><br />
Val: <input name="val" /><br />
<input type="submit" value="submit"/>
</form>
</body>
</html>`
func formHandler(rw http.ResponseWriter, req *http.Request) {
rw.Write([]byte(form))
}
// for real routing take a look at gorilla/mux package
func handler(rw http.ResponseWriter, req *http.Request) {
switch req.Method {
case "POST":
post(rw, req)
case "GET":
if req.URL.String() == "/form" {
formHandler(rw, req)
return
}
get(rw, req)
}
}
func main() {
fmt.Println("go to http://localhost:8080/form")
// thats the default webserver of the net/http package, but you may
// create custom servers as well
err := http.ListenAndServe("localhost:8080", http.HandlerFunc(handler))
if err != nil {
fmt.Println(err)
}
}
