I have a value proxy object in my client side which I have created using a Request Context. I use the same request context to save that object. Till here its fine.
Now there is a new requirement where I need to send the same object to the server (for different purpose) to the server before the actual save in the flow. How can I do that?
I tried to create a new request context and then send object with that, but I got an error saying thats not allowed.
Thanks.
You have to duplicate/clone it. As it's a ValueProxy it shouldn't be a problem. The issue is that there's no easy and clean way to clone a proxy.
The cleanest solution is to use AutoBeanUtils.getAutoBean and then an AutoBeanVisitor to visit each property and set it on another proxy.
An easier way is to serialize the proxy into a ProxyStore and deserialize it, which will create a distinct proxy.
Related
I'm trying to implement a custom credential-store (with custom CredentialStoreSpi implementation) to integrate with data-sources through credential-reference.
The idea is to use a vault service with rotating passwords, and, for now, when I start WildFly, it calls CredentialStoreSpi.retrieve() and initializes data-source with current password, but if I flush data-source and request a new connection there are no calls to .retrieve(). And if I rotate password, then, it fails to create connection with username/password error, and still do not call for a new password.
Looking in specs I see that data-source connection security has a config to some "Reauth Plugin Class Name", but I can't find any clues on what is that.
There is any way to change this behavior and force that any new connection should require password directly from credential-store?
Found this spec: https://docs.wildfly.org/20/wildscribe/subsystem/datasources/data-source/ExampleDS/index.html#attr-reauth-plugin-class-name
reauth-plugin-class-name The fully qualified class name of the reauthentication plugin implementation
Looking at web but find no documentation on this.
Anyone knows what is that? Could it help in this use case?
if the credential store is updated externally you have to do a reload of that credential store. Maybe calling the retrieve method or reloading the credential store in the server at a certain intervals might make sense
I am getting started with OPCUA and eclipse milo and I am trying to understand how to best inform the client that a value or node has changed in the server.
So far my guess is that I need to trigger an event in the node that has changed, and then the client should monitor/subscribe to events in such node. Am I right on this?
If my understanding is correct, which event is most appropriated to trigger for this purpose?
I am using a free UI OPCUA client to test my server changes, and I need to refresh manually to observe my changes. I was expecting that by triggering the correct (OPCUA standard) event I would indicate the client to refresh automatically, is this possible?
Thanks!
You don't need Events to notify a client of an attribute change - that's the entire point of Subscriptions and MonitoredItems.
The client creates a MonitoredItem for the Value attribute (or any other attribute) and the server will report changes when that attribute changes.
As far as what you need to do as a user of the Milo Server SDK - see the ExampleNamespace. Your namespace implements the onDataItemCreated and other related methods to be notified that a client has created a MonitoredItem and you should start sampling values for it.
Inside of an OSGi component / service I'd need a JSON-representation of a resource (pages, CF etc) exactly like retrieving it via Sling model selector (resource.model.json).
Unfortunately being inside an OSGi component or service, there's no (sling) request object available.
Is there a way to get the json representation (with all the component's model exporters) without creating a http-request to localhost?
that's not a problem as long as you have access to the resource.
First you need to make sure that your Model can deliver the json via a method call. See Get .model.json as String for an explanation on how to do this.
If you are done with that, use the ModelFactory to "getModelFromResource". This will create an instance of your SlingModel for the given resource. Just call the method you created before to get your json.
See https://sling.apache.org/apidocs/sling10/org/apache/sling/models/factory/ModelFactory.html
Your model should probably have adaptables= {Resource.class} - if you adapt from Request there might be trouble ahead.
HTH,
OliG
I'm facing a weird problem in GWT. I generate an excel file on server side for users to download. But after the download the file should get deleted.
I have put logic to delete it on server-Side on 2 occasions. One when user logs out and another when browser is closed.
When the user logs out, it works perfectly as it has enough time to make a call to the server whereas in case of addclosehandler, it loses connection and file remains as it is.
i.e. the method on server side does not get executed.
I tried to find another way to call the method directly by importing the package and inheriting in gwt.xml. But an error was thrown at the compile time and rightly so that server side cant be inherited.
Please get me out of this.
Thanks in advance.
But after the download the file should get deleted. I have put logic
to delete it on server-Side on 2 occasions.
This does not have to do anything with the client. I don't know excactly how your progam works but generally it should work like this:
Client makes a request
Servlet generates the bytes (Is there really a need to store the bytes in a file?)
sends them to client
And that's it.
I have a question regarding this topic.Like for Client Server Applications
1) is it necessary to load database directly into the Application.
Suppose if I have a DB in the back end and My application has to connect to that DB and display the results on the View for this do I need to Add DB into the Application directly.
2) can we access any DB or a File on the Remote server and show the required results.( with out adding that particular DB or A File into the application directly). How can we do this.
I saw a similar question in stackoverflow one answer was to use a PList, I am new to this.I am browsing the net but not able to get clear results. I lost many of my interviews because of this question.
Thanks,
1) is it necessary to load database
directly into the Application.
Suppose if I have a DB in the back end
and My application has to connect to
that DB and display the results on the
View for this do I need to Add DB into
the Application directly.
I'm not sure I understand this question. No, you don't need to load a database directly into a client in a client-server architecture. Normally, when I think of a design where a server has a database, I imagine there's some kind of way for the client to query the server for information. Perhaps it's making HTTP requests, which the server parses into a query, runs the query, and then returns the results (perhaps in XML form?).
2) can we access any DB or a File on
the Remote server and show the
required results.( with out adding
that particular DB or A File into the
application directly). How can we do
this.
Are you asking if it's possible, in general, to access a server database from a client? Yes, of course. (See above, re: HTTP Requests).
Any arbitrary file? That depends on how the server is set up. Again, HTTP is one protocol works that way; if you send an HTTP query like "GET someimage.png HTTP/1.0", the server could just be grabbing the whole file someimage.png and sending it back in the response. (Technically, it's not necessarily snarfing a whole file -- it could be creating that PNG dynamically since there's nothing in the HTTP protocol that says it must be sending an existing file -- but that's outside the scope of your question.)
I lost many of my interviews because
of this question.
Not to sound too snarky, but interviews are often won and lost not because you don't know the answer, but when you can't communicate effectively. You haven't phrased your question(s) here particularly well.