// handle the data request, calling the optional callback when complete
// handles GET/POST with no key to get the whole collection or create a new item
// handles GET/PUT/DELETE with a key to get, update and remove the given item
// this method will validate data and check permissions
// after completion, the optional callback is called with key and item reference
// item is nil for DELETE and GET(all)
// key is nil for GET(all)
// method specifies which HTTP method was used
func (self *dataHandler) handleRequest(ancestor *datastore.Key,
callback func(method string, key *datastore.Key, item Ided)) {
id := getID(self.r)
var key *datastore.Key
var item Ided
// handle request with no specific ID
if len(id) == 0 {
switch self.r.Method {
case "GET":
// we return a JSON list of all items
self.getAll(ancestor)
case "POST":
// we create a new item and return it
key, item = self.createEntry(ancestor)
default:
check(ErrUnsupported)
}
} else {
// we are working with a specific id, validate it
var err error
key, err = datastore.DecodeKey(id)
check(err)
if key.Incomplete() {
check(ErrUnknownItem)
}
self.checkUser(key)
// handle the get, update and delete methods
switch self.r.Method {
case "GET":
item = self.get(key)
case "PUT":
item = self.update(key)
case "DELETE":
self.delete(key)
default:
check(ErrUnsupported)
}
}
// call the callback if we have one
if callback != nil {
callback(self.r.Method, key, item)
}
}