Golang appengine.NewContext函数代码示例

// GET http://localhost:8080/profiles/ahdkZXZ-ZmVkZXJhdGlvbi1zZXJ2aWNlc3IVCxIIcHJvZmlsZXMYgICAgICAgAoM
//
func (u ProfileApi) read(r *restful.Request, w *restful.Response) {
	c := appengine.NewContext(r.Request)

	// Decode the request parameter to determine the key for the entity.
	k, err := datastore.DecodeKey(r.PathParameter("profile-id"))
	if err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}

	// Retrieve the entity from the datastore.
	p := Profile{}
	if err := datastore.Get(c, k, &p); err != nil {
		if err.Error() == "datastore: no such entity" {
			http.Error(w, err.Error(), http.StatusNotFound)
		} else {
			http.Error(w, err.Error(), http.StatusInternalServerError)
		}
		return
	}

	// Check we own the profile before allowing them to view it.
	// Optionally, return a 404 instead to help prevent guessing ids.
	// TODO: Allow admins access.
	if p.Email != user.Current(c).String() {
		http.Error(w, "You do not have access to this resource", http.StatusForbidden)
		return
	}

	w.WriteEntity(p)
}

// POST http://localhost:8080/profiles
// {"first_name": "Ivan", "nick_name": "Socks", "last_name": "Hawkes"}
//
func (u *ProfileApi) insert(r *restful.Request, w *restful.Response) {
	c := appengine.NewContext(r.Request)

	// Marshall the entity from the request into a struct.
	p := new(Profile)
	err := r.ReadEntity(&p)
	if err != nil {
		w.WriteError(http.StatusNotAcceptable, err)
		return
	}

	// Ensure we start with a sensible value for this field.
	p.LastModified = time.Now()

	// The profile belongs to this user.
	p.Email = user.Current(c).String()

	k, err := datastore.Put(c, datastore.NewIncompleteKey(c, "profiles", nil), p)
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}

	// Let them know the location of the newly created resource.
	// TODO: Use a safe Url path append function.
	w.AddHeader("Location", u.Path+"/"+k.Encode())

	// Return the resultant entity.
	w.WriteHeader(http.StatusCreated)
	w.WriteEntity(p)
}

// DELETE http://localhost:8080/users/1
//
func (u *UserService) removeUser(request *restful.Request, response *restful.Response) {
	c := appengine.NewContext(request.Request)
	id := request.PathParameter("user-id")
	err := memcache.Delete(c, id)
	if err != nil {
		response.WriteError(http.StatusInternalServerError, err)
	}
}

// GET http://localhost:8080/users/1
//
func (u UserService) findUser(request *restful.Request, response *restful.Response) {
	c := appengine.NewContext(request.Request)
	id := request.PathParameter("user-id")
	usr := new(User)
	_, err := memcache.Gob.Get(c, id, &usr)
	if err != nil || len(usr.Id) == 0 {
		response.WriteErrorString(http.StatusNotFound, "User could not be found.")
	} else {
		response.WriteEntity(usr)
	}
}

// PUT http://localhost:8080/profiles/ahdkZXZ-ZmVkZXJhdGlvbi1zZXJ2aWNlc3IVCxIIcHJvZmlsZXMYgICAgICAgAoM
// {"first_name": "Ivan", "nick_name": "Socks", "last_name": "Hawkes"}
//
func (u *ProfileApi) update(r *restful.Request, w *restful.Response) {
	c := appengine.NewContext(r.Request)

	// Decode the request parameter to determine the key for the entity.
	k, err := datastore.DecodeKey(r.PathParameter("profile-id"))
	if err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}

	// Marshall the entity from the request into a struct.
	p := new(Profile)
	err = r.ReadEntity(&p)
	if err != nil {
		w.WriteError(http.StatusNotAcceptable, err)
		return
	}

	// Retrieve the old entity from the datastore.
	old := Profile{}
	if err := datastore.Get(c, k, &old); err != nil {
		if err.Error() == "datastore: no such entity" {
			http.Error(w, err.Error(), http.StatusNotFound)
		} else {
			http.Error(w, err.Error(), http.StatusInternalServerError)
		}
		return
	}

	// Check we own the profile before allowing them to update it.
	// Optionally, return a 404 instead to help prevent guessing ids.
	// TODO: Allow admins access.
	if old.Email != user.Current(c).String() {
		http.Error(w, "You do not have access to this resource", http.StatusForbidden)
		return
	}

	// Since the whole entity is re-written, we need to assign any invariant fields again
	// e.g. the owner of the entity.
	p.Email = user.Current(c).String()

	// Keep track of the last modification date.
	p.LastModified = time.Now()

	// Attempt to overwrite the old entity.
	_, err = datastore.Put(c, k, p)
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}

	// Let them know it succeeded.
	w.WriteHeader(http.StatusNoContent)
}

// PATCH http://localhost:8080/users
// <User><Id>1</Id><Name>Melissa Raspberry</Name></User>
//
func (u *UserService) updateUser(request *restful.Request, response *restful.Response) {
	c := appengine.NewContext(request.Request)
	usr := new(User)
	err := request.ReadEntity(&usr)
	if err == nil {
		item := &memcache.Item{
			Key:    usr.Id,
			Object: &usr,
		}
		err = memcache.Gob.Set(c, item)
		if err != nil {
			response.WriteError(http.StatusInternalServerError, err)
			return
		}
		response.WriteEntity(usr)
	} else {
		response.WriteError(http.StatusInternalServerError, err)
	}
}

// PUT http://localhost:8080/users/1
// <User><Id>1</Id><Name>Melissa</Name></User>
//
func (u *UserService) createUser(request *restful.Request, response *restful.Response) {
	c := appengine.NewContext(request.Request)
	usr := User{Id: request.PathParameter("user-id")}
	err := request.ReadEntity(&usr)
	if err == nil {
		item := &memcache.Item{
			Key:    usr.Id,
			Object: &usr,
		}
		err = memcache.Gob.Add(c, item)
		if err != nil {
			response.WriteError(http.StatusInternalServerError, err)
			return
		}
		response.WriteHeader(http.StatusCreated)
		response.WriteEntity(usr)
	} else {
		response.WriteError(http.StatusInternalServerError, err)
	}
}