I have two custom channels one of which is a reload channel. How can I configure symmetricds so no data to be transferred on the normal channel until all the initial data is send and processed by the reload channel? In the sym_incoming_batch table I saw that I have many batches send by the reload channel and a few by the normal channel in between the ones send by the reload channel. I think this is the reason why I get some duplicate key error sometimes and since I’m not using the default data loader (I’m using postgres_bulk) I can’t use the fallback logic which would fix this problem.
I tried to prioritize the reload channel by setting processing_order to 1 for the reload channel and 2 for the other channel, but this didn’t work.
Please help me with this. Tell me if you need more information.
Thanks
I recommend trying configuring all synchronization on "reload" channel. This would order all new db changes after current reload is finished.
Is it possible to shutdown the application(s) that use(s) the central DB while process of registering and reloading a new node is done?
Related
I am using firestore with queries and i am getting data but something in network tab is loading none stop
as you can see its over a minute
should i be concerned about it?
It's hard to be certain without seeing the code that produces this problem, but most likely you're using a realtime listener (onSnapshot) in your code.
Such a listener keeps an active , open connection between the client and the server, so that the database can send a notification to the client when the data changes. The Chrome network tool shows this as a content download, because indeed data trickles in over this connection.
So likely what you're seeing is a normal part of Firestore's protocol for realtime, bi-directional communication between the client and server, but again.
I'm sending data from my backend every 10 seconds and I wanted to display that data in reactjs. I've searched on the net to use socket.io to display real-time data. Is there a better way to use it?
If you're dead set on updating your data every 10 seconds, it would make more sense to make a request from the client to the server, as HTTP requests can only be opened from client to server. By using HTTP requests, you won't need to use socket.io, but socket.io is an easy alternative if you need much faster requests.
Depending on how you are generating the data being sent from your backend, specifically if you are using a database, there is most likely a way to subscribe to changes in the database. This would actually update the data in realtime, without a 10 second delay.
If you want a more detailed answer, you'll have to provide more detail regarding your question: what data are you sending? where is it coming from or how are you generating it?
I'm working on an autodialer feature, in which an agent will get a call when I trigger the button from the frontend (using react js language), and then automatically all the leads in the agent assigned portal will get back-to-back calls from agent number. However, because this process is automatic, the agent won't know who the agent has called, so I want to establish a real-time connection so that I can show a popup on the frontend that contains information about the lead who was called.
I'm looking for a way (and not even sure if this is possible) to update an Angular expression on my HTML page when data is sent to an API.
For example, say I have $scope.message on my .html page. Is there a way I can send a message to an API (e.g. http://...?message=foo) and have my page update with the message sent?
Also, I need the $scope.message to be updated in an Angular Service so it is available to multiple pages within my website.
I am wanting this to be a live update, but if not, I am happy with some code executing on a timer or something similar.
Any suggestions appreciated.
UPDATE
I'm guessing it may not be possible, but just in case I haven't explained it correctly, I'll try and simplify it.
I can only find information about using AngularJS to send GET commands OUT to a URL and receive data back. I need to send a JSON string TO my Angular site to update a variable. So basically as a field updates in my database, I want another server application to send an alert to my Angular site to update the status of this value live. I don't really want to run a constant check of the database if I don't have to.
I am open to any other suggestions on how to achieve this.
if you don't care about old school browsers, you can try using WebSocket, it is similar to a TCP socket, which allows you to push from server to client. I would create a service that manages the websocket connection, and update scope when receiving message. Hope this help. More info here: https://developer.mozilla.org/en-US/docs/Web/API/WebSockets_API
I have a C# Web API project on server side and on front-end I have ExtJS 4.2.1 (Javascript framework client).
There is a section in my app where I request to start a long running process (about 5 minutes) and I want to show the user the status of the process being executed.
Basically, the process will run a special calculation for every employee in the database (about 800), so I want to let the user know which Employee is being processed in that moment.
So I was thinking in two ways of doing this, and maybe I don't know if having both is ok.
Use SignalR to show the information of the process in Real Time.
Write to a database table all the process log (every employee that its being processed).
If I use the first approach, if the user close the browser he will loose all the information about the process and if he log into the app again he will only see the actual status.
If I use the second approach, if he log into the app again he could see all the information, and using maybe a timer on client side the data could be refreshed every 5 seconds.
Does anyone have implemented something like this? Any advice is appreciated.
You should use a combination of the two. When you have calculated a employee save the state to the database and publish the change on a service bus.
Let SignalR pick these messages up and forward them to the client. This way the user will see old state when he connects and new state then they arrive with SignalR. I have created a Event aggregator proxy that makes this very easy.
https://github.com/AndersMalmgren/SignalR.EventAggregatorProxy/wiki
Follow the wiki to set it up, here is a demo project
https://github.com/AndersMalmgren/SignalR.EventAggregatorProxy/tree/master/SignalR.EventAggregatorProxy.Demo.MVC4
Live demo
http://malmgrens.org/Signalr/
This may be a naive question but I was planning to create a new channel just before the existing channel timed out to make sure that my client was never without a channel. I thought I was being pretty clever until I read this caveat in the google channel api docs:
One Client Per Channel Per Page
A client can only connect to one channel per page. If an application needs to send multiple types of data to a client, aggregate it on the server side and send it to appropriate handlers in the client’s socket.onmessage callback.
I'm new to this, but it's not obvious to me how the channel unique identifies the page to which it is connected. Is there something in the javascript for channel.open() call that identifies the page it is being called in?
Thanks.
The channel javascript creates a hidden iframe with a given id (on production). The communications takes place within the iframe. The javascript code will always access that iframe (and hence channel).
When you close the socket and channel, the hidden iframe will be destroyed. Afterwards you can create a new channe for the page.