go/doc/progs/error3.go

66 строки
1.3 KiB
Go

// compile
// Copyright 2011 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// This file contains the code snippets included in "Error Handling and Go."
package main
import (
"net/http"
"text/template"
)
func init() {
http.Handle("/view", appHandler(viewRecord))
}
// STOP OMIT
func viewRecord(w http.ResponseWriter, r *http.Request) error {
c := appengine.NewContext(r)
key := datastore.NewKey(c, "Record", r.FormValue("id"), 0, nil)
record := new(Record)
if err := datastore.Get(c, key, record); err != nil {
return err
}
return viewTemplate.Execute(w, record)
}
// STOP OMIT
type appHandler func(http.ResponseWriter, *http.Request) error
func (fn appHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
if err := fn(w, r); err != nil {
http.Error(w, err.Error(), 500)
}
}
// STOP OMIT
type ap struct{}
func (ap) NewContext(*http.Request) *ctx { return nil }
type ctx struct{}
func (*ctx) Errorf(string, ...interface{}) {}
var appengine ap
type ds struct{}
func (ds) NewKey(*ctx, string, string, int, *int) string { return "" }
func (ds) Get(*ctx, string, *Record) error { return nil }
var datastore ds
type Record struct{}
var viewTemplate *template.Template
func main() {}