blob: 77ad544f964f4ccf91a26ca7956cb80d47cfca95 [file] [log] [blame]
// +build OMIT
package main
import (
"bytes"
"fmt"
"io"
"log"
"net/http"
)
type errorHandler func(http.ResponseWriter, *http.Request) error
func handleError(f errorHandler) http.HandlerFunc {
return func(w http.ResponseWriter, r *http.Request) {
err := f(w, r)
if err != nil {
log.Printf("%v", err)
http.Error(w, "Oops!", http.StatusInternalServerError)
}
}
}
func handler(w http.ResponseWriter, r *http.Request) error {
name := r.FormValue("name")
if name == "" {
return fmt.Errorf("empty name")
}
fmt.Fprintln(w, "Hi,", name)
return nil
}
// resp implements http.ResponseWriter writing
type dummyResp struct {
io.Writer
h int
}
func newDummyResp() http.ResponseWriter {
return &dummyResp{Writer: &bytes.Buffer{}}
}
func (w *dummyResp) Header() http.Header { return make(http.Header) }
func (w *dummyResp) WriteHeader(h int) { w.h = h }
func (w *dummyResp) String() string { return fmt.Sprintf("[%v] %q", w.h, w.Writer) }
func main() {
http.HandleFunc("/hi", handleError(handler))
// ListenAndServe is not allowed on the playground.
// http.ListenAndServe(":8080", nil)
// In the playground we call the handler manually with dummy requests.
// Fake request without 'name' parameter.
r := &http.Request{}
w := newDummyResp()
handleError(handler)(w, r)
fmt.Println("resp a:", w)
// Fake request with 'name' parameter 'john'.
r.Form["name"] = []string{"john"}
w = newDummyResp()
handleError(handler)(w, r)
fmt.Println("resp b:", w)
}