Actor Framework Discussions
Actor Framework + Interfaces: Why does calling an interface method hit the prototype instead of the implementation?
Solved!
I assume by "directly" he means send the Producer messages straight to Consumer rather than through Server.
Apologies for long post. tl;dr: Don't cross the streams; never share enqueuers across the tree, and don't add backchannel methods to do that either (like a sneaky User Event or something).
Long version:
I agree this is a bad idea. It seems like it'll save some time now- and it will- because you're sending message from P straight to C instead of P to S to C, but you WILL pay for it later. So, take the time to write the boring boilerplate code that S uses when it gets a message from P.
I'd also suggest two things to consider.
First is to reframe the way you're thinking about your system. I don't know what data you're acquiring, but clearly you have some way to "get data" and some way to "handle data". So for now I'll call this "raw data" and "processed data". Try to mentally reframe your layout as "My server needs some raw data, so it gets it from Producer. Once it has that raw data, it sends it to Consumer to use that data." Try to consider that each "message hop" is "doing" something different, and it starts to feel less like arbitrarily following the rules, and more about "ah, each item does ONE thing".
Say your Producer reads voltage from a multimeter. The Producer ONLY knows "hey I got some voltages. Here ya go." The Server receives that message and "reinterprets" that as "Hey I got some raw unscaled position sensor measurements- let me send it to the Scaling actor." That reinterpretation is a valuable step that can really help keep things cohesive.
The second thing to consider is that you COULD have the Consumer be a dependency injection of the Producer. This is a more tricky method to get your head around, so I wouldn't recommend it as an early project, but it's not hard to actually implement. In this paradigm, the Producer always knows it's going to send data to SOMETHING- so, when Server first launches the Producer, it sends a consumer Actor (NOT an enqueuer- an Actor object itself!) to the Producer. Producer stores this in its private data (this would likely be a generic Interface for "thing that can consume Producer's data").
Once Producer gets data, instead of sending it up the chain to Server, it sends it straight to Consumer- but note that Consumer is now a child of Producer, not of Server. In this method, Server doesn't get to talk to Consumer, but maybe it doesn't have to.
Another example- say you're taking pictures from a camera and sending them to a database. Server doesn't need to actually talk to the database, so maybe it could just send the Database Actor* to the Producer. Once Producer takes a new image, it sends it straight to the Database Actor, who puts it into a database. Perhaps it ALSO sends the picture to Server, who displays it on a front panel- but those are two different functionalities, even though the payload of a given message is the same in either case.
*This is a contrived example, because in reality you might need some sort of status info on the database to show up in Server, in which case you'd want Database to be a child of Server, not of Producer. And there's also the discussion of whether or not something that interacts with a database should be an Actor, rather than a regular vanilla Object, since simply writing to a database doesn't require an async message loop. But this post is long enough already.
Hello Aristos,
Here is the block diagram of what I was trying to do. I was trying to get access to only the implemented method of Consumer Actor, but when running I only get prototype method of Interface (Int_DataTransfer). I do not launch the Consumer Actor from Producer. Instead I have Server Actor that launches every other Actors.
Ultimately, when I start to write my program, I will have multiple devices (multiple Actors) that stream data, I will acquire and process data (Acquisition Actor), user interface (UI Actor) and logging Actor etc. So instead of sending data through a Caller Server Actor, I was thinking to send data directly to relevant actor using Interfaces if I have a reference to that target Actors implemented reference. (I only wanted to access implemented Interface methods.)
@mhrrm05 wrote:
Here is the block diagram of what I was trying to do. I was trying to get access to only the implemented method of Consumer Actor, but when running I only get prototype method of Interface (Int_DataTransfer). I do not launch the Consumer Actor from Producer. Instead I have Server Actor that launches every other Actors.
The 'To More Specific Class' primitive is incorrectly used. Your code is forcing a concrete class wire to the Interface wire, causing the symptoms you see. You should be able to wire the Consumer class directly to the upper element of your Bundle-By-Name.
Are you trying to access the Consumer class's methods both, directly and via actor message? Both approaches can co-exist, as long as you have valid justifications for them.
