Is there a way to enforce single device login on parse.com? - ios

Question

I am developing an app where I need to be very API request frugal, the less requests the better. The problem is every user has settings and messages and I want to avoid to pull for possible changes on every wake up. And I can't rely on that every user enables push notifications.
My approach is as a compromise to enforce that a user can only be logged in with one device. If they try to login with another device (via facebook) they get an error message where they can choose to either cancel the login or go ahead and logout the other device remotely.
Is this possible?

Answer 1

I found a solution to this problem.
Query number of sessions after login
If the number is greater than 1 ask user what do
logout other device (and go ahead) -> call "deleteAllOtherSessions"
cancel login (and go back to login screen) -> call "deleteLastSession"
Cloud code:
Parse.Cloud.define("getSessionCount", function(request, response) {
if (request.user == null) {
reportError("findSessions", "userCheck", 0);
response.error("invalid user");
return
}
var query = new Parse.Query(Parse.Session);
query.find({
success: function(results) {
response.success(results.length);
},
error: function(error) {
response.error(error);
}
});
});
Parse.Cloud.define("deleteAllOtherSessions", function(request, response) {
if (request.user == null) {
reportError("deleteAllOtherSessions", "userCheck", 0);
response.error("invalid user");
return
}
var sessionToken = request.params.sessionToken;
var query = new Parse.Query(Parse.Session);
// this query will find only sessions owned by the user since
// we are not using the master key
query.find().then(function(results) {
var promises = [];
_.each(results, function (result) {
if(result.get("sessionToken") != sessionToken) {
promises.push(result.destroy());
}
});
return Parse.Promise.when(promises);
}).then(function() {
response.success(true);
},
function(error) {
response.error(error)
});
});
Parse.Cloud.define("deleteLastSession", function(request, response) {
if (request.user == null) {
reportError("deleteLastSession", "userCheck", 0);
response.error("invalid user");
return
}
var sessionToken = request.params.sessionToken;
var query = new Parse.Query(Parse.Session);
query.descending("createdAt");
// this query will find only sessions owned by the user since
// we are not using the master key
query.find().then(function(results) {
var promises = [];
console.log(results);
promises.push(results[0].destroy());
return Parse.Promise.when(promises);
}).then(function() {
response.success(true);
},
function(error) {
response.error(error)
});
});
Hope that helps somebody.