I am using Azure Notification Hubs to deliver push notifications to an android/iPhone devices.
My general flow is:
1.Every time the user opens the mobile app, a call is made to the PNS
(APNS/GCM) and gets an updated device token.
2. The device token is then sent to the server.
3. The server executes the following code to register the token:
RegistrationDescription reg;
if (deviceType == DeviceType.Iphone)
{
reg = new AppleRegistrationDescription(deviceToken, new string[] { userId.ToString() });
}
else
{
reg = new GcmRegistrationDescription(deviceToken, new string[] { userId.ToString() });
}
reg = await hub.CreateRegistrationAsync(reg);
It works great, but my question is, should I be tracking those device tokens in my server for some reason? For example save them in a table for later use or other scenarios I could be facing, or it's intended to use that way(without saving them in a table).
Your code creates a lot of duplicates, by duplicate I mean different registrations with same PNS handle (APNS device token or GCM registration id). NH has de-duplication logic which prevents your devices from receiving multiple copies of same message, but it increases internal storage space and slows system down.
So there is recommendation:
On each device your create and store some GUID-like identifier;
You pass that identifier on server together with PNS handle;
On server you do hub.GetRegistrationByTagAsync(deviceGuid, 100);
If registration returned, then update it with received PNS handle
(even if PNS handle the same - just to prevent expiration);
If result is empty, then you create new registration specifying device GUID as a tag;
Also there is new API which allows you to do only one call and not use any tags if you don't need them. https://msdn.microsoft.com/en-us/magazine/dn948105.aspx Look at topic Case 2: The Back End Manages Devices in Notification Hubs. It is not very good explanation maybe but feature is new. If any questions about that API then I can answer.
Related
I've been looking for a good way to do, but haven't found anything that doesn't seem hacky. I want to signal the client without going through the database and a subscription. For example, in a game I want to send a message to the client to display "Player 1 almost scores!". I don't care about this information in the long run, so I don't want to push it to the DB. I guess I could just set up another socket.io, but I'd rather not have to manage a second connection if there is a good way to go it within meteor. Thanks! (BTW, have looked at Meteor Streams, but it appears to have gone inactive)
You know that Meteor provides real-time communication from the server to clients through Publish and Subscribe mechanism, which is typically used to send your MongoDB data and later modifications.
You would like a similar push system but without having to record some data into your MongoDB.
It is totally possible re-using the Meteor Pub/Sub system but without the database part: while with Meteor.publish you typically return a Collection Cursor, hence data from your DB, you can also use its low-level API to send arbitrary real-time information:
Alternatively, a publish function can directly control its published record set by calling the functions added (to add a new document to the published record set), changed (to change or clear some fields on a document already in the published record set), and removed (to remove documents from the published record set). […]
Simply do not return anything, use the above mentioned methods and do not forget calling this.ready() by the end of your publish function.
See also the Guide about Custom publications
// SERVER
const customCollectionName = 'collection-name';
let sender; // <== we will keep a reference to the publisher
Meteor.publish('custom-publication', function() {
sender = this;
this.ready();
this.onStop(() => {
// Called when a Client stops its Subscription
});
});
// Later on…
// ==> Send a "new document" as a new signal message
sender.added(customCollectionName, 'someId', {
// "new document"
field: 'values2'
});
// CLIENT
const signalsCollectionName = 'collection-name'; // Must match what is used in Server
const Signals = new Mongo.Collection(signalsCollectionName);
Meteor.subscribe('custom-publication'); // As usual, must match what is used in Server
// Then use the Collection low-level API
// to listen to changes and act accordingly
// https://docs.meteor.com/api/collections.html#Mongo-Cursor-observe
const allSignalsCursor = Signals.find();
allSignalsCursor.observe({
added: (newDocument) => {
// Do your stuff with the received document.
}
});
Then how and when you use sender.added() is totally up to you.
Note: keep in mind that it will send data individually to a Client (each Client has their own Server session)
If you want to broadcast messages to several Clients simultaneously, then the easiest way is to use your MongoDB as the glue between your Server sessions. If you do not care about actual persistence, then simply re-use the same document over and over and listen to changes instead of additions in your Client Collection Cursor observer.
It's completly fine to use the database for such a task.
Maybe create a collection of "Streams" where you store the intended receiver and the message, the client subscribe to his stream and watches any changes on it.
You can then delete the stream from the database after the client is done with it.
This is a lot easier than reinventing the wheel and writing everything from scratch.
I'd like to determine if a user is currently "online" or connected to the Meteor server.
I need this information before I send the user message, If the user is not connected I'd like to send the message via email.
I know that for traditional web applications that are totally state-less the definition of "online" use is a bit not clear but since modern web frameworks rely on websocket, a user is supposed to be online if a websocket is open.
The question is does Meteor include a method to determine if a user is connected or not?
Summarized: yes, there is such a mechanism.
There are for example package, that store the active login connections of the users with the meteor server and make them available either via an own collection or as part of the user profile.
See: https://github.com/dburles/meteor-presence
(Creates a new collection, called Presences)
or https://github.com/dan335/meteor-user-presence/
(Creates a user's profile entry, called presence. However, has also a collection to store and update the information in the background)
or https://github.com/mizzao/meteor-user-status
(Thanks to blueren in the comments)
Code example (from the first listed package)
Meteor.onConnection(function(connection) {
// console.log('connectionId: ' + connection.id);
Presences.insert({ _id: connection.id });
connections[connection.id] = {};
tick(connection.id);
connection.onClose(function() {
// console.log('connection closed: ' + connection.id);
expire(connection.id);
});
});
If you don't want to rely on the packages you may make use of that mechanism yourself.
See: https://docs.meteor.com/api/connections.html#Meteor-onConnection
I have Wp8.1 Silverlight app that receives push notification (WNS) from Mobileservice (the old azure service).
I therefore wanted to update to the new service because of the new features. I have now created/upgraded a new server to use App Service - Mobile App. And tested push notification with the sample app from azure (everything works).
Going back to my app WP8.1 -> Adding the new package Microsoft.Azure.Mobile.Client through NuGet (2.0.1), there is the issue that the Microsoft.WindowsAzure.Mobile.Ext does not contain the 'GetPush' extension. It seems like it is missing it? looking to the WP8 version, it only registers to MPNS, and I need WNS. So I do not know if any other assembly could be used.
Can I add another assembly reference?
Update
The following code lets me register the device on the server, and I can see the device register correctly. where the channelUri and the installationInformation are retrieved by the client and send to the server.
Installation ins = new Installation();
ins.Platform = NotificationPlatform.Wns;
ins.PushChannel = uTagAndChan.ChannelUri;
ins.Tags = uTagAndChan.Tags;
ins.InstallationId = uTagAndChan.installationInformation;
await hubClient.CreateOrUpdateInstallationAsync(ins);
Sending a test toast-notification to the registered tags, results in the following error :
The Token obtained from the Token Provider is wrong
Searching on this issue I found Windows Store App Push Notifications via Azure Service Bus. Which the proposed solution says to register to the notification hub directly from the app, I would rather not have the app to have directly access to the hub. But is this the only way? (mind you the answer was not accepted, but I will try it all though it is not a desired solution)
Update
Registering for notifications via client (WP8.1 Silverligt), makes a registration to MPNS, which I do not want.
The snippet on the server registers a WNS, the two registrations can be seen here:
The URI retrieval is done using
var channel = await Windows.Networking.PushNotifications.PushNotificationChannelManager.CreatePushNotificationChannelForApplicationAsync();
which in the description states it returns a WNS. This seems to infer that the registration I am doing on the server (code snippet in the top) is correct and the registration on the client is faulty.
But the registration on the image seems wrong. Shouldn't the PNS Identifier be different for the two registrations? also expiration date seems wrong ?
How to mend this since the GetPush() (which was available in the sample registered the client correctly for notifications) does not exist in the NuGet package?
Update
I read one place that deleting and recreating the NotificationHub could help. I will try this today. Even IF it works, it would be more desirable to have the solution, and to know if the registrations are done correctly?
Temporary solution:
Deltede, recreated, inserted Package SID and Secret. And it works again (strange)!
Still interested in the underlying issue!
Deleted and recreated the service, setting all the same settings made it work again.
I had same issue with my UWP. But in my case I had issue with self signed certificate.
When I set the AppxPackageSigningEnabled property to True (in .csproj) then notifications stopped working and I got "The token obtained from the Token Provider is wrong" (Test send from Azure Portal).
The certificate must have same issuer as Publisher in Identity element in .appxmanifest file.
To start off, I'd like to state that this is my first dive into Asterisk related applications, and that I'm mostly a web developer.
My workplace uses an MSP that installed Asterisk/FreePBX to manage our phone systems. The GUI is pretty intuitive and after reading and getting a bit lost I figured I'd come here and see how to go about setting this up.
I was tasked with building a simple application to reset user passwords through both a web interface (completed) and a phone interface - by dialing a number, dialing their ID card #, and then having their password reset. I'm a Systems Administrator and have access to all necessary applications, servers, etc. I can pick things up fairly easy and I was told I'd have enough time to figure this out and get it done.
This is what I need in terms of pseudocode when the user calls a specific extension:
recording('pwResetCardID'); // Play a "Please enter your ID # to reset PW" greeting.
function getCardID() {
cardID = input(); // Input 4-5 digits using the dialpad and save it to a var.
verify = get('http://some.site/endpoint/cardid/'.$cardid); // Send a GET request.
if verify { // If we got a successful response (200)
recording('pwChanged'); // Tell the user their password has changed
} else { //
recording('errorCardID'); // Otherwise tell them to try again
getCardID(); // Recur the function.
}
}
getCardID();
If the cardID is valid, their PW is changed on the other end of my node.js application, and I simply need the GET request to be sent out and the user notified of the success (or failure)
You can start from doc describing asterisk dialplan
Probably need use func_CURL, Read application, Playbavk and Goto
You need put new dialplan in extensions_custom.conf and setup use it via custom apps module
Is there any way to write a security rule or is there any other approach that would make possible only for currently connected (not authenticated) user to write/read certain location - admin should also be able to write/read?
Can a rule be written that disallows users to read of complete list of entries and let them read only entry that matches some identifier that was passed from client?
I'm trying to exchange some data between user and Node.js application through Firebase and that data shouldn't be able to read or write by anyone else other than user and/or admin.
I know that one solution would be that user requests auth token on my server and uses it to authenticate on Firebase and that would make it possible to write rule which prevents reads and writes. However, I'm trying to avoid user connecting to my server so this solution is not first option.
This is in a way session based scenario which is not available in Firebase but I have
some ideas that could solve this kind of problem - if implemented before session management:
maybe letting admin write into /.info/ location which is observed by client for every change and can be read only by active connection - if I understood correctly how .info works
maybe creating .temp location for that purpose
maybe letting admin and connected client could have more access to connection information which would contain some connection unique id, that can be used to create location with that name and use it inside rule to prevent reading and listing to other users
Thanks
This seems like a classic XY problem (i.e. trying to solve the attempted solution instead of the actual problem).
If I understand your constraints correctly, the underlying issue is that you do not wish to have direct connections to your server. This is currently the model we're using with Firebase and I can think of two simple patterns to accomplish this.
1) Store the data in an non-guessable path
Create a UUID or GID or, assuming we're not talking bank level security here, just a plain Firebase ID ( firebaseRef.push().name() ). Then have the server and client communicate via this path.
This avoids the need for security rules since the URLs are unguessable, or close enough to it, in the case of the Firebase ID, for normal uses.
Client example:
var fb = new Firebase(MY_INSTANCE_URL+'/connect');
var uniquePath = fb.push();
var myId = uniquePath.name();
// send a message to the server
uniquePath.push('hello world');
From the server, simply monitor connect, each one that connects is a new client:
var fb = new Firebase(MY_INSTANCE_URL+'/connect');
fb.on('child_added', newClientConnected);
function newClientConnected(snapshot) {
snapshot.ref().on('child_added', function(ss) {
// when the client sends me a message, log it and then return "goodbye"
console.log('new message', ss.val());
ss.ref().set('goodbye');
});
};
In your security rules:
{
"rules": {
// read/write are false by default
"connect": {
// contents cannot be listed, no way to find out ids other than guessing
"$client": {
".read": true,
".write": true
}
}
}
}
2) Use Firebase authentication
Instead of expending so much effort to avoid authentication, just use a third party service, like Firebase's built-in auth, or Singly (which supports Firebase). This is the best of both worlds, and the model I use for most cases.
Your client can authenticate directly with one of these services, never touching your server, and then authenticate to Firebase with the token, allowing security rules to take effect.