> Nothing complex about two images exchanging messages, its not even complex to > transmit objects via fuel, you even transmit a debugger or any part of the > live environment or even make an "internet" of images that join objects > together. Sky is the limit. Pharo already provides you will all the > tools/libraries to do this.
Yes. That’s why I asked for better practices. > > A streamsocket (not to be confused with regular sockets) will delay the > messages (a collection of bytes) until they arrive to the receiver or until > they have reached the timeout period. Offline mode is pretty much obligatory > even for plain old internet web apps because of drops in connection or the > plain fact a connection can become slow. Offline mode is to me of first importance. Let’s say I have a sets of Pharo app (nodes). Each one are independent running on different devices/computers. I want to exchange information between them according to some kind of contracts and also on connection availability. What I find different from usual message exchanges between two images is that I want to have full control on it. Plus I consider images offline by default (meaning two images have different versions of the same info). So conflict is the norm. Also, I don’t want to send message remotely (with behavior), I just want to send/share an information and sync them (when possible). Connection between 2 images can be through a network but eventually through a serial connection (usb cable, Bluetooth,...). So what I try to do as a proto is having connection controlled by my apps (I put the app offline (not by switching off wifi but by switching logically). I can see nodes availability and activate connexion manually then see if conflict resolution is ok, + I log every connecitions changes and exchanges). This is my plans for now but it may change ! ^^ > > I used streamsockets in my Pharo to Python bridge (Atlas) because the > execution was not necessary synchronous , I was sending Python command to a > 3d application from Pharo and I had to make sure that the bridge was working > even in the case of a command that could take hours to execute like a > rendering process. I’ll look at stream sockets and mq stuffs. Cheers, Cédrick > > One cool trick I did was to send the Python errors back to Pharo and trigger > them as Pharo's regular MessageNotUnderstood , this is a nice way to make > sure that you can fix a wrong message after it has been executing without > going to the image that is executing it. > > The limitation with sockets which what every frameworks uses because AFAIK > they are the only means to communicate remotely is that they are not top > performance so that mean that you can send long loops but executing > communication inside long loops will either slow you down considerably or > simply timeout your socket. Sockets can timeout from both ends if they feel > that for some reason they lost communication with the other side and reached > their timeout period. Timeout period is customization. > > This is a problem I did not tackle with my implementation because I dont > think there can be an actual practical solution better than avoiding this > scenario. > > Only shared memory seems to overcome this but it can be used only locally and > not remotely (aka on same computer) . > >> On Wed, Oct 25, 2017 at 4:41 PM Cédrick Béler <cdric...@gmail.com> wrote: >> I had a look and this is not (natively) possible. >> >> The idea of the off-line mode would be to delay messages that are sent to >> the peer until a connection is established. >> >> I think I have to try to do it by myself (like having a list of information >> exchange that wait until a connexion is established). >> >> What I try to do is not as complex as two general image exchanging messages >> on objects (like on TelePharo). >> >> I just want a repository of information (mainly a collection of static >> information/data versions) on both peers to be synchronized when a >> connection is established. >> >> >> >> >> >>> Le 25 oct. 2017 à 15:31, Denis Kudriashov <dionisi...@gmail.com> a écrit : >>> >>> What is offline mode? >>> >>> 2017-10-25 15:10 GMT+02:00 Cédrick Béler <cdric...@gmail.com>: >>>> Thanks Denis. I will ! I knew I have seen a telephoto component that >>>> could help but forgot about it ! >>>> >>>> Do you know if it’s possible to handle offline mode ? >>>> >>>> >>>> >>>>> Le 25 oct. 2017 à 15:05, Denis Kudriashov <dionisi...@gmail.com> a écrit : >>>>> >>>>> Look at Seamless https://github.com/dionisiydk/Seamless. >>>>> >>>>> 2017-10-25 14:21 GMT+02:00 Cédrick Béler <cdric...@gmail.com>: >>>>>> Hi all, >>>>>> >>>>>> I want to connect two applications (1 by image, each one on a different >>>>>> computer) so as as to exchange information (data) between them. >>>>>> >>>>>> So my question is about the best (smalltalk) practices to connect two >>>>>> app/image and exchange data. >>>>>> >>>>>> I imagine either with a direct connection through a network (TCP Socket, >>>>>> Web socket, pure HTTP with Zinc) and/or with a serial connection. >>>>>> At first, without any « security ». But later, information exchanges >>>>>> will be encrypted. >>>>>> >>>>>> I’ve seen some information on how to use SerialPort, or even FileStream. >>>>>> I could do it (or at least simulate it with HTTP). What are the other >>>>>> options ? Socket ? >>>>>> Do we have P2P libs (I couldn’t find) with eventually discovery features >>>>>> ? >>>>>> >>>>>> Any comment / suggestion / pointers are greatly welcome. >>>>>> >>>>>> TIA. >>>>>> >>>>>> Cédrick >>>>> >>>> >>> >>
