Hi All, i implemented two simple ping checks one specifically for s7 and one in generall to check reachability of a port. Which can simply be copied.
I also wrote a connection-manager which checks the connection and recreates it if neccessary. Our szenario is that we want to read data in a loop and the higher the sampling frequency the better. I do not want to waste that on the "liveness" check of the connection. Best S7 could do is every 100ms i heared. Also i load the driver for the s7 directly because in osgi the classloader stuff does not work. I put my working code into examples/connection-manager and created a pull request. i did not grasp the code of PooledDriverManager in this short time to integrate. Feel free to adapt/change pieces of my code or give me feedback. Gunther Gruber On 26.03.19 15:24, Christofer Dutz wrote: Hi All, I would agree that a void type and exceptions would allow a more fine-grained reporting of what's going on. Sort of: - "Yeah ... I am a S7 400, but I don't support the S7-TIA protocol" - "No connection under this number" (no connection possible) - "You're not allowed to connect" - "Invalid credentials" - ... Maybe we should do that ASAP, adding it to the API, but have it report "Not Implemented" for now and to create JIRA tickets for the individual drivers ping implementations. Chris Am 26.03.19, 14:44 schrieb "Julian Feinauer" <[email protected]><mailto:[email protected]>: Hi Gunther, thats really great to hear : ) When I remember correctly the idea was... 1. Extend the PlcConnection interface with a "ping()" method (Boolean? Throw Exception if not possible?) 2. Implement the Ping functionality for each plc with a sensible "operation" (not sure what this could be for S7... read the SLZ or something?) 3. Use this feature as "keep alive" e.g. for the PooledDriverManager does that make sense? Julian Am 26.03.19, 13:55 schrieb "Gunther Gruber" <[email protected]><mailto:[email protected]>: Sure I like to contribute. I guess by that you mean checking out the code and create a pull request with something working. I like your idear with the ping check. I will focus on implementing a function for the ping check, which can be reused later. Gunther > Hi Gunther, > > good catch : ) > In fact, the isConnected() implementation is currently not soo god. > In fact it checks if the underlying communication channel from netty is connected (which does not know that it is disconnected yet, in your case). > We already had discussions to introduce a real "request" based implementation like "ping()" which sends a request. > > Furthermore, for your use case there is the PooledDriverManager which does implicitly what you do... throws away a not working connection and issues a new one, if needed, but that’s a separate topic. > > I think we should spend some effort into this "ping" functionality. > Perhaps you can even assist with the implementation Gunther, what do you think? > > Julian > > Am 26.03.19, 11:19 schrieb "Gunther Gruber" <[email protected]><mailto:[email protected]>: > > Put it another way, isConnected does not work as i expect it > > plcConnection.isConnected() returns true even when i disconnect the vpn (maybe of some tcp/ip keepalive?) > > this is the snippet of code which i expect to work (instead of the thread which reconnects ever 10 minutes) > while (doCollect) { > > try { > if (plcConnection == null || plcConnection.isConnected() == false) { > plcConnection = initPLC(config.get(CONNECTION_KEY)); > } > } catch (PlcConnectionException e) { > logger.log(Level.WARNING, "error connecting with driver", e); > plcConnection = null; > incrementalSleep(); > break; > } > > // Create a new read request: > // - Give the single item requested the alias name "value" > PlcReadRequest.Builder builder = plcConnection.readRequestBuilder(); > > Gunther Gruber > > > -- Gunther Gruber Software Developer [cid:[email protected]] Intelligent Data Analytics GmbH & Co. KG c/o TechQuartier Platz der Einheit 2 60327 Frankfurt Telefon: +49 6421/4805274 Telefax: +49 6421/4805275 E-Mail: [email protected] Internet: www.ida-analytics.de<http://www.ida-analytics.de/> Unternehmenssitz: Frankfurt am Main | Handelsregister beim Amtsgericht: Frankfurt am Main, Registernummer: HRA 49357 | USt. ID-Nr.: DE310205810 | Finanzamt: Frankfurt am Main Persönlich haftende Gesellschafterin: IDA Intelligent Data Analytics GmbH | Sitz: Frankfurt am Main | Handelsregister beim Amtsgericht: Frankfurt am Main | Handelsregister-Nummer: HRB 106805 | Geschäftsführer: Mohamed Ayadi, Nils Björn Krugmann, Matthias Leinweber, Marc Seidemann If you are not the addressee, please inform us immediately that you have received this e-mail by mistake, and delete it. We thank you for your support.
