I use the perform javascript call to perform an action on the server, like this:
subscription.perform('action', {...});
However, from what I've seen there seems to be no builtin javascript "success" callback, i.e. to let me know the action is concluded on the server's side (or possibly failed). I was thinking about sending a broadcast at the end of the action like so:
def action(data)
...do_stuff
ActionCable.server.broadcast "room", success_message...
end
But all clients subscribed to this "room" would receive that message, possibly resulting in false positives. In addition, from what I've heard, message order isn't guaranteed, so a previous broadcast inside this action could be delivered after the success message, possibly leading to further issues.
Any ideas on this or am I missing something completely?
Looking at https://github.com/xtian/action-cable-js/blob/master/dist/cable.js and , https://developer.mozilla.org/en-US/docs/Web/API/WebSocket#send(), perform just executes WebSocket.send() and returns true or false, and there is no way to know whether your data has arrived. (That is just not possible with WebSockets, it seems.)
You could try using just a http call (I recommend setting up an api with jbuilder), or indeed broadcasting back a success message.
You can solve the order of the messages by creating a timestamp on the server, and sending it along with the message, and then sorting the messages with Javascript.
Good luck!
Maybe what you are looking for is the trasmit method: https://api.rubyonrails.org/v6.1.3/classes/ActionCable/Channel/Base.html#method-i-transmit
It sends a message to the current connection being handled for a channel.
Related
I am newbie on Fix in general and I have started from QuickFix to make practice. I apology in advance from the following trivial questions.
I have understood that to handle ExecutionReport I need to use crack() method inside FromApp() and implementing OnMessage().
But what I have two questions :
1) What happens if during a Partially fill order ExecutionReport message suddenly session drops, which is the way to handle this situation. Trying to reconnect and Send a request ? Please Can you provide a simple explanation in steps and what QuickFix Api method should I use ?
2) If I need to implement a FixEngine to handle dropcopy should I be aware of something in particular ?
Thank you for your help
1). Just make sure ResetOnDisconnect parameter is set to N for your trading session: ResetOnDisconnect=N (docs)
QuickFix will be automatically attempting to reconnect every ReconnectInterval seconds;
Once connected (with ResetOnDisconnect=N) it will also automatically exchange last known message sequence numbers with the FIX server, and the ones lost during the disconnection will be re-sent - so without a line of code you will receive the missing messages.
Also, if disconnection was for a longer period of time, you may want to send Order Status Request (H) message to the FIX server to receive actual ExecutionReport for your pending orders.
2) The question is too general for me to answer...
I am using a FIX protocol to communicate with one of our counterparties. I have used Camel with Spring to build my communication routes.
I have a requirement where in my counterparty is expecting an ACK for every request it sends to me.
For example:
TradeCaptureRequestAck in response to TradeCaptureRequest
AllocationReportAck in response to AllocationReport
Confirmation_Ack in response to Confirmation
They are expecting a response irrespective of what happens at our end (even if something fails or exception occurs).
One way I know we can intercept the incoming message via MessageFactory. We can create a custom messagefactory and inject it in while creating QuickFixJComponent bean.
Problem with this approach is at factory level I will just be able to get the message type like TradeCaptureReport, AllocationReport etc. but not the content because factory only creates (and returns) the appropriate Message object. Actual work of populating this message object with incoming message data happens in Session class I guess (not sure about this).
Can someone please tell me if there is a way I can get or intercept the request message as soon as it reaches the route so that I can send the appropriate ACK to counterparty?
I am looking into the Swift Vapor framework.
I am trying to create a controller class that maps data obtained on an SSL link to a third party system (an Asterisk PBX server..) into a response body that is sent over some time down to the client.
So I need to send received text lines (obtained separately on the SSL connection) as they get in, without waiting for a 'complete response' to be constructed.
Seeing this example:
return Response(status: .ok) { chunker in
for name in ["joe\n", "pam\n", "cheryl\n"] {
sleep(1)
try chunker.send(name)
}
try chunker.close()
}
I thought it might be the way to go.
But what I see connecting to the Vapor server is that the REST call waits for the loop to complete, before the three lines are received as result.
How can I obtain to have try chunker.send(name) send it's characters back the client without first waiting for the loop to complete?
In the real code the controller method can potentially keep an HTTP connection to the client open for a long time, sending Asterisk activity data to the client as soon as it is obtained. So each .send(name) should actually pass immediately data to the client, not waiting for the final .close() call.
Adding a try chunker.flush() did not produce any better result..
HTTP requests aren't really designed to work like that. Different browsers and clients will function differently depending on their implementations.
For instance, if you connect with telnet to the chunker example you pasted, you will see the data is sent every second. But Safari on the other hand will wait for the entire response before displaying.
If you want to send chunked data like this reliably, you should use a protocol like WebSockets that is designed for it.
I need your help with the gwt requestfactory
considering following scenario:
I get an existing entity (let's say a invoice) from the server:
InvoiceEntityProxy invoice = request1.getInvoice();
I want to make some changes, so I edit it with a new request:
InvoiceEntityProxy editableInvoice = request2.edit(invoice);
//make some changes to editableInvoice
Now I send the changes made with the second request to the server, to create a preview:
request2.createPreview(editableInvoice);
When the request is sent, the invoice proxy is frozen and I re-enable editing by assigning the proxy to a new request:
editableInvoice = request3.edit(editableInvoice);
If everything is okay, i want to update the proxy and send it to the server, using the latest request:
request3.update(editableInvoice);
But the changes never arrive on the server, because the latest request (request3) doesn't know anything about the changes made to the proxy assigned to the request2.
I thought about following solutions:
I could redo the changes on the latest proxy. But for that, I've to iterate over all attributes and set them again (not very friendly solution, because I've to adjust the method each time I add some attributes to the proxy)
Another approach would be to send the proyx without an id to the server and send the id as second parameter of the update-method. But this would be a shame, because not only the deltas would be sent to the server (which is one of the greate features of the requestFactory).
So what is the best and most common practice to let the request3 know about the changes already made to the proxy, when it was assigned to another request.
You simply forget to call fire(). Example
request2.createPreview(editableInvoice).fire();
Bear in mind that if the following request depend on the result of the previous one, you should put your code in the OnSuccess methode because the request is asynchronous
It's also possible to append multiple requests
EDIT
It important to use the same request for the edit and fire operations. So replace this line
request.update(editableInvoice);
with
request3.update(editableInvoice);
Nice! I found the solution for my problem.
I still have an instance of the original proxy, because the edit() method of the context always return a new instance of the proxy. So I save the original proxy before sending any request.
After each successful request, I re-enable editing the proxy by call the edit method again:
editableInvoice = request3.edit(editableInvoice);
Now the crux:
I can set the original proxy of a proxy, which is used to consider if it changed and what changed. This is done by using AutoBean and set the PARENT_OBJECT Tag like this:
AutoBean<InvoiceEntityProxy> editableInvoiceBean = AutoBeanUtils.getAutoBean(editableInvoice);
AutoBean<InvoiceEntityProxy> originalInvoiceBean = AutoBeanUtils.getAutoBean(originalInvoice);
editableInvoiceBean.setTag(Constants.PARENT_OBJECT, originalInvoiceBean);
On the next request all changed properties are send to the server again.
Thank you for your help and thank you for the hint with the AutoBean #Zied Hamdi
You also can use AutoBeans to duplicate the object before you start changing it. You can keep the original one untouched then request.edit() it and apply changes (introspection like changes) from the "dirty" object.
You'll maybe have to do some research on how to handle EntityProxies since they are "special AutoBeans" : I had to use special utility objects to serialize them to json (available in GWT). So there might be some special handling in doing a deep copy too.
There is an issue maybe with GWT keeping only one version of each EntityProxy (I never checked if it is global or only in the context of a request)
I was hoping someone can shed some light on how the Quickfixn engine handles outgoing FIX messages... I have an outgoing connection set up, and I'm getting heartbeats. When I generate an outgoing message however, it gets rejected because it says that tag 58 is invalid for this message type... (35=AE) ... Normally, if this was an inbound connection, I could just modify the Data Dictionary and everything would be fine... but seeing as how this is an outgoing connection, plus I have my
UseDataDictionary property set to 'N' ... what does the quickfix engine use to validate the outgoing message? Can something be changed to allow the engine to pass the message ? Or is the only resolution not to include this tag in my outgoing message?
Any help on this matter would be greatly appreciated.
Edit-
The message is getting rejected by the quickfix engine. The message that I'm constructing and the respective reject message are:
8=FIX.4.4 9=400 35=AE 34=38 49=XXX 52=20130528-23:11:04.040 56=YYY 31=1.3022 32=1000000.00 39=0 55=EUR/USD 58=ABCD 60=20130528-22:34:52.000 64=20130531 75=20130529 570=N 571=ABCD 5495=0 5971=1302200.00 552=1 54=2 37=ABCD 453=3 448=LP1-DBAB 447=D 452=17 448=XXX 447=D 452=1 448=XXX 447=D 452=19 15=EUR 120=USD 10=082
8=FIX.4.4 9=130 35=3 34=38 49=YYY 52=20130528-23:11:04.283 56=XXX 45=38 58=Tag not defined for this message type 371=58 372=AE 373=2 10=033
I've seen incoming messages get rejected by the quickfix engine because the data dictionary didn't have the correct specs for the message... I thought this might be the same thing but the outgoing connection doesn't seem to use the data dictionary.
Your FIX library does not reject a message. The message is sent to the counter-party instead, which then rejects your message as invalid upon receiving and validating it. And the reason for that is because tag 58, if present, must be a part of “NoSides repeating group (tag 552), which in your case it is not, making the message ill-formed. What you have to do is send a "logically" correct message. I recommend you refer to the appropriate FIX protocol specification for a reference on how to construct a correct message.
Vlad's answer is correct, but I want to alert you to one other danger in your question.
I have my UseDataDictionary property set to 'N'
I am 90% sure you don't want to do this. Whatever you think you're gaining by using =N is probably based on a misunderstanding of something.
Without a DD, you can't read messages with repeating groups, because the engine won't know what fields go in what group.
In practice, every venue uses repeating groups. Therefore, you'll need to set UseDataDictionary=Y and you need to specify an xml file with DataDictionary=<file>.
The only reason we allow =N in QF/n is to be consistent with QF/C++ and QF/j.