I'm making a mobile app for an audio chat like the clubhouse. Does anyone knows how to get existing rooms? In other words, how could you tell when a room is created and destroyed? I wonder if a channel is something like a river that constantly flows even without people in it.
that's an interesting question. Creating and destroying can be done in multiple ways which mainly depends upon your use case:
Pre-defined channels: If you want your users to join some existing channel itself then just pass the name of the channel to the joinChannel() method.
User can create their own channel: Process is still the same, in this case you just have to pass the channel name that the user gives as an input.
Further the process is simple the user calls the leaveChannel() method to drop off a particular call. And then the destroy() method releases all the Agora RtcEngine resources.
Related
There are numerous articles on "how to implement update service" is already present. However, I have serious question below:
when will pass get updated technically? what is the trigger for updating?
When will be passbook's update service be called?
when update push notification is clicked by user
when pass is opened by user
silently done in background
when automatic update is off and user opens a pass
Please help
Pass updates can be initated in one of two ways:
The users does a pull-to-refresh on the pass.
You send a push notification to the device.
In the case of number 2, the device responds to the push notification by reaching out to the service specified by the pass's WebServiceUrl.
It sends the device identifier and pass type identifier. The web service is responsible for determining the passes that need updating and it returns a set of serial numbers. It does this by looking at the update tag and applies whatever mechanism makes sense for the pass.
The device will then request an updated pass for each of these serial numbers.
The process is described in far more detail in Apple's Documentation:
https://developer.apple.com/library/content/documentation/UserExperience/Conceptual/PassKit_PG/Updating.html#//apple_ref/doc/uid/TP40012195-CH5-SW1
Is there any way other than getting all Channel Groups and checking each one individually? I am wanting to go through and have the server remove the channel from all of the Channel Groups who contain that channel.
I have the client unsubscribing as it should, but in the event that it does not unsubscribe properly (browser crash/loss of connection/etc). I know using presence and detecting leave/timeout is probably the best way to handle this. But, it is just not something we can do in this first implementation.
I have a Web-Service application, i need to send scheduled GET methods to my server and if a change has happened with my incoming data i have to inform my user about the changes. When my app is in the foreground(in min thread) i fetch some data and pıpulate my tableview, my problem is, i can't realize how to create a scheduled method to the same data source(mean server) and if a new thing has been added, either my app is on bacground or not, inform user(alert) about the changes. Can anyone please share any idea-link.. Thanks in advance
This is exactly what push notifications were designed for, and are, technically the best way to solve the problem.
It does mean the task of 'checking' for new data is shifted to your server but the user is better suited as a push notification will happen, even if your app is not running.
I recommend using a system like Urban Airship.
I've got a JMS messaging system implemented with two queues. One is used as a standard queue second is an error queue.
This system was implemented to handle database concurrency in my application. Basically, there are users and users have assets. One user can interact with another user and as a result of this interaction their assets can change. One user can interact with single user at once, so they cannot start another interaction before the first one finishes. However, one user can be in interaction with other users multiple times [as long as they started the interaction].
What I did was: crated an "interaction registry" in redis, where I store the ID of users who begin an interaction. During interaction I gather all changes that should be made to the second user's assets, and after interaction is finished I send those changes to the queue [user who has started the interaction is saved within the original transaction]. After the interaction is finished I clear the ID from registry in redis.
Listener of my queue will receive a message with information about changes to the user that need to be done. Listener will get all objects which require a change from the database and update it. Listener will check before each update if there is an interaction started by the user being updated. If there is - listener will rollback the transaction and put the message back on the queue. However, if there's something else wrong, message will be put on to the error queue and will be retried several times before it is logged and marked as failed. Phew.
Now I'm at the point where I need to create a proper integration test, so that I make sure no future changes will screw this up.
Positive testing is easy, unfortunately I have to test scenarios, where during updates there's an OptimisticLockFailureException, my own UserInteractingException & some other exceptions [catch (Exception e) that is].
I can simulate my UserInteractingException by creating a payload with hundreds of objects to be updated by the listener and changing one of it in the test. Same thing with OptimisticLockFailureException. But I have no idea how to simulate something else [I can't even think of what could it be].
Also, this testing scenario based on a fluke [well, chance that presented scenario will not trigger an error is very low] is not something I like. I would like to have something more concrete.
Is there any other, good, way to test this scenarios?
Thanks
I did as I described in the original question and it seems to work fine.
Any delays I can test with camel.
Disclaimer: This is a follow-on question from my other question about NServiceBus which was answered very thoroughly.
My current question is this: If a website is built to be 'dumb' like the article referred to, above, suggests then how does the following scenario work?
A user registers on a website by filling out a form with relevant details. When the user clicks the 'submit' button on the form the web application takes the form data and creates a message which it sends to the application tier using NServiceBus and Bus.Send(). The application tier goes about the business of creating the new user and publishing the event that the user has been created (Bus.Publish()) so that other processes can do their thing (email the new user, add the user to a search index, etc, etc).
Now, since the web application in this scenario relies entirely on the application tier for the creation of the new user instance, how does it get to know about the user's id? If I didn't use NServiceBus in this scenario but, rather, let the website issue an in-process call to a DAL I'd use NHibernate's GuidComb() strategy to create the identifier for the new user before persisting the new row in the database. If the message handler application which receives the command to create a new user (in the current scenario) uses the same strategy, how is the userId communicated back to the web application?
Do I have to apply a different strategy for managing identifiers in a scenario such as this?
You're free to come up with an ID to use as a correlation identifier by putting it in your message in the web application, allowing it to be carried around whatevery processes are initiated by the message.
That way, you can correlate the request with other events around your system, if only they remember to supply the correlation ID.
But it sounds like you want your user ID to be fed back to you in the same web request - that cannot easily be done with an asynchronous backend, which is what messaging gives you.
Wouldn't it be acceptable to send an email to the user when the user has been created, containing a (secret) link to some kind of gateway, that resumes the user's session?
Wouldn't the UI be able to listen to the bus for the "user created" event? And then you could correlate either by having the event include some kind of event ID linking back to the "user creation requested" event or against some other well known data in the event (like the user name). Though you probably also have to listen to multiple events, such as "user creation failure" event.
This is not unlike normal AJAX processing in a web browser. Technically, you don't block on the out of band call back to the web server. You invoke the call and you asynchronously wait for a callback.