1 // Copyright 2011 The Go Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style 3 // license that can be found in the LICENSE file. 4 5 // This file contains the code snippets included in "Error Handling and Go." 6 7 package main 8 9 import ( 10 "net/http" 11 "text/template" 12 ) 13 14 func init() { 15 http.Handle("/view", appHandler(viewRecord)) 16 } 17 18 // STOP OMIT 19 20 func viewRecord(w http.ResponseWriter, r *http.Request) error { 21 c := appengine.NewContext(r) 22 key := datastore.NewKey(c, "Record", r.FormValue("id"), 0, nil) 23 record := new(Record) 24 if err := datastore.Get(c, key, record); err != nil { 25 return err 26 } 27 return viewTemplate.Execute(w, record) 28 } 29 30 // STOP OMIT 31 32 type appHandler func(http.ResponseWriter, *http.Request) error 33 34 func (fn appHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) { 35 if err := fn(w, r); err != nil { 36 http.Error(w, err.Error(), 500) 37 } 38 } 39 40 // STOP OMIT 41 42 type ap struct{} 43 44 func (ap) NewContext(*http.Request) *ctx { return nil } 45 46 type ctx struct{} 47 48 func (*ctx) Errorf(string, ...interface{}) {} 49 50 var appengine ap 51 52 type ds struct{} 53 54 func (ds) NewKey(*ctx, string, string, int, *int) string { return "" } 55 func (ds) Get(*ctx, string, *Record) error { return nil } 56 57 var datastore ds 58 59 type Record struct{} 60 61 var viewTemplate *template.Template 62 63 func main() {} 64
