// pushStackHandler adds an element into a Stack and returns 200 and the element.
func (c *Conn) pushStackHandler(w http.ResponseWriter, r *http.Request, stack *pila.Stack) {
if r.Body == nil {
log.Println(r.Method, r.URL, http.StatusBadRequest,
"no element provided")
w.WriteHeader(http.StatusBadRequest)
return
}
var element pila.Element
err := element.Decode(r.Body)
if err != nil {
log.Println(r.Method, r.URL, http.StatusBadRequest,
"error on decoding element:", err)
w.WriteHeader(http.StatusBadRequest)
return
}
stack.Push(element.Value)
stack.Update(c.opDate)
log.Println(r.Method, r.URL, http.StatusOK, element.Value)
w.Header().Set("Content-Type", "application/json")
// Do not check error as we consider our element
// suitable for a JSON encoding.
b, _ := element.ToJSON()
w.Write(b)
}
// statusStackHandler returns the status of the Stack.
func (c *Conn) statusStackHandler(w http.ResponseWriter, r *http.Request, stack *pila.Stack) {
stack.Read(c.opDate)
log.Println(r.Method, r.URL, http.StatusOK)
w.Header().Set("Content-Type", "application/json")
// Do not check error as we consider that a flushed
// stack has no JSON encoding issues.
b, _ := stack.Status().ToJSON()
w.Write(b)
}
// deleteStackHandler deletes the Stack from a database.
func (c *Conn) deleteStackHandler(w http.ResponseWriter, r *http.Request, database *pila.Database, stack *pila.Stack) {
stack.Flush()
// Do not check output as we validated that
// stack always exists.
_ = database.RemoveStack(stack.ID)
log.Println(r.Method, r.URL, http.StatusNoContent)
w.WriteHeader(http.StatusNoContent)
return
}
// peekStackHandler returns the peek of the Stack without modifying it.
func (c *Conn) peekStackHandler(w http.ResponseWriter, r *http.Request, stack *pila.Stack) {
var element pila.Element
element.Value = stack.Peek()
stack.Read(c.opDate)
log.Println(r.Method, r.URL, http.StatusOK, element.Value)
w.Header().Set("Content-Type", "application/json")
// Do not check error as we consider our element
// suitable for a JSON encoding.
b, _ := element.ToJSON()
w.Write(b)
}
// popStackHandler extracts the peek element of a Stack, returns 200 and returns it.
func (c *Conn) popStackHandler(w http.ResponseWriter, r *http.Request, stack *pila.Stack) {
value, ok := stack.Pop()
if !ok {
log.Println(r.Method, r.URL, http.StatusNoContent)
w.WriteHeader(http.StatusNoContent)
return
}
stack.Update(c.opDate)
element := pila.Element{Value: value}
log.Println(r.Method, r.URL, http.StatusOK, element.Value)
w.Header().Set("Content-Type", "application/json")
// Do not check error as we consider our element
// suitable for a JSON encoding.
b, _ := element.ToJSON()
w.Write(b)
}
// sizeStackHandler returns the size of the Stack.
func (c *Conn) sizeStackHandler(w http.ResponseWriter, r *http.Request, stack *pila.Stack) {
stack.Read(c.opDate)
log.Println(r.Method, r.URL, http.StatusOK, stack.Size())
w.Header().Set("Content-Type", "application/json")
// Do not check error as we consider the size
// of a stack valid for a JSON encoding.
w.Write(stack.SizeToJSON())
}