问题
I need to create an application, where GAE server will always talk with just one client (i.e. one message should be always sent just to one client).
I do the following -
Python:
def get(self):
# generate token, when page is loaded
client_id = uuid.uuid4().hex
token = channel.create_channel(client_id)
template_values = {'token': token,
'client_id': client_id
}
self.response.out.write(template.render('page.html', template_values))
def post(self):
# reply to the client
...
client_id = self.request.get('id')
channel.send_message(client_id, message)
Javascript:
sendMessage = function(field) {
$.ajax({
type: "POST",
url: "/",
data: "f=" + field + "&id=" + "{{ client_id }}", // WARNING!
contentType: "application/x-www-form-urlencoded",
success: function(data) {
}
});
};
onOpened = function() {
connected = true;
sendMessage('opened');
};
onMessage = function(msg) {
alert(msg.data);
};
onError = function(err) {
alert(err);
};
onClose = function() {
alert("close");
};
// open new session
channel = new goog.appengine.Channel('{{ token }}'); // WARNING!
socket = channel.open();
socket.onopen = onOpened;
socket.onmessage = onMessage;
socket.onerror = onError;
socket.onclose = onClose;
It works well, but with such scenario both token
and client_id
are passed to the client. Is it OK?
回答1:
There's no technical reason not to do this. If you're worried about security, the token is far more valuable: an attacker who could listen to your traffic could take the token and listen to channel messages in a different context. The clientid wouldn't let them do that.
But I do have a question: why not return the message in the POST response, rather than sending a message over the channel? Or is the sample code just simplified for the example?
来源:https://stackoverflow.com/questions/9420123/is-it-ok-to-pass-both-token-and-client-id-to-the-client-when-channel-api-is-used