December 2016 - Pharo-dev - lists.pharo.org

Re: [Pharo-dev] Berlin 2016-12-19

by stepharong

Indeed, immensely sad. Humanity is under regression. When you see that in Mali they destroyed the oldest world library. What sadden me the most is that in case of attacks in France, these attacks were made by brainwashed french citezen against french citizen contrary to what ugly "politician" would like that we think. > https://en.wikipedia.org/wiki/2016_Berlin_attack > > It is really sad that these things happen, that so many innocent people > are killed and hurt. It makes me even more sad that I seem to be getting > used to this, that should not be the case, at all. > > Sven > > -- Using Opera's mail client: http://www.opera.com/mail/

Dec. 21, 2016

Re: [Pharo-dev] MQTT for Pharo

by Henrik Johansen

> On 21 Dec 2016, at 16:52 , Sven Van Caekenberghe <sven(a)stfx.eu> wrote: > >> >> On 21 Dec 2016, at 16:04, Henrik Johansen <henrik.s.johansen(a)veloxit.no> wrote: >> >>> >>> On 21 Dec 2016, at 14:57 , Sven Van Caekenberghe <sven(a)stfx.eu> wrote: >>> >>> Hendrik, >>> >>> Thank you for this detailed feedback. >>> >>>> On 21 Dec 2016, at 12:44, Henrik Johansen <henrik.s.johansen(a)veloxit.no> wrote: >>>> >>>> Hi Sven! >>>> One thing I noticed when testing the RabbitMQ client with keepalive > 0, was connection being closed and all subscriptions lost when receiving large payloads, due to timeout before the keepalive packet could be sent before waiting to receive next object. >>> >>> Indeed, I used my Stamp (STOMP) Rabbit MQ client as a model for the MQTT one - there is a lot of similarity, especially in concept. >>> >>> Keep alive processing is not that easy. I tried to do it by using read timeouts as a source of regular opportunities to check for the need to process keep alive logic. But of course, if you have no outstanding read (in a loop), that won't work. >>> >>> The fact that receiving a large payload would trigger an actual keep alive time out is not something that I have seen myself. It seems weird that the reading/transferring of incoming data would not count as activity against keep alive, no ? >> >> I never had a chance to investigate fully, but I distinctly remember having the same reaction! >> It's quite awhile ago now, so my memory might be hazy, take the following with an appropriate amount of grains of salt. >> >> The first times I encountered it, it seemed quite random, occuring after extended periods of client inactivity after receiving only small payloads... >> Setting a much shorter keepalive timeout than the default was/is very useful in reproducing/verifying if it is an issue. >> The timeouts then occurred relatively shortly after I'd received a single payload with no other activity, and disappeared once I removed the resetting of lastActivity timestamp on reads, indicating that for at least rabbitmq (3.5 was the version at the time, I believe), receiving data was *not* being counted as keep-alive activity. >> >> The issue of receiving large payloads blocking writing in time was still unresolved, consistently cut off in the middle of (its own!) multi-MB payload transfers due to keepalive packet not being sent. >> I couldn't see a solution other than abandoning the elegant single-threaded approach and do keepalive as a separate high-priority process, but the architectural choice for the app changed at this point to not include a MQ in first delivery, so the more involved rewrite for doing so before deploying in production, kinda got stranded :/ > > Instinctively it feels like messaging and multi-MB payloads would not be a good fit, at least I would suspect that they are an edge case. But maybe I am wrong. > > I think that the code in StampMedium>>#readBodyBytes: and StampMedium>>#readBodyString: could be refactored to use a loop with chunk buffers and at the same time check the elapsed time to fire back keep alive pings if necessary. A ping too much would not hurt, better safe than sorry. But is is hard to catch any/all network slowdowns, any IO operation could hang/timeout. > > But all this would assume that the problematic situation can be recreated. Absolutely, far from certain the MQTT server implementations work the same. This is the test code I used for rabbit: consumer1 := StampClient new timeout:1; heartbeat: 5000; login: 'guest'; passcode: 'guest'; open; subscribeTo: '/exchange/testall'; yourself. [[ consumer1 runWith:[:message | Transcript crShow: '1 read: ', message body]] ensure: [consumer1 close]] forkAt: Processor userInterruptPriority . producer := StampClient new login: 'guest'; passcode: 'guest'; open; yourself. [1 to: 10000 do: [:i | producer sendText: i asString to: '/exchange/testall']] forkAt: Processor systemBackgroundPriority. Sometimes, but not always, this would fail, either during processing, or some time after. A screenshot of how it looks when a disconnect happens during processing due to heartbeat failing can be found at: https://tresor.it/s#HN4RG9PEX1SYyKy4NcM31w Cheers, Henry

Dec. 21, 2016

Berlin 2016-12-19

by Sven Van Caekenberghe

https://en.wikipedia.org/wiki/2016_Berlin_attack It is really sad that these things happen, that so many innocent people are killed and hurt. It makes me even more sad that I seem to be getting used to this, that should not be the case, at all. Sven

Dec. 21, 2016

Re: [Pharo-dev] MQTT for Pharo

by Sven Van Caekenberghe

> On 21 Dec 2016, at 15:47, Ben Coman <btc(a)openinworld.com> wrote: > > You might like to collaborate with Tim and Craig. > http://forum.world.st/Graphing-weather-data-td4927701.html > cheers -ben Hmm, that code seems to be quite incomplete (from what I can see publicly): not all packet types and their IO is fully implemented, there are no unit tests, there is no client, and none of the more complex quality of service levels 0, 1 & 2 logic/flow, and there are no functional unit tests against public sandbox/test servers. > On Wed, Dec 21, 2016 at 10:17 PM, Sven Van Caekenberghe <sven(a)stfx.eu> wrote: >> >>> On 21 Dec 2016, at 15:11, phil(a)highoctane.be wrote: >>> >>> FWIW get yourself an account at http://enco.io >> >> OK, I'll put it on my list of things to look at. >> >>> The devportal has mqtt endpoints so that we can integrate with that and possibly have some market place solutions offered and running with Pharo. >>> >>> I have a small EnCoClient class in Pharo that works. Now making the API support more extensive. >>> >>> Docs: http://docs.enco.io/docs/device-sensor-apis >>> >>> Phil >>> >>> On Wed, Dec 21, 2016 at 2:59 PM, Sven Van Caekenberghe <sven(a)stfx.eu> wrote: >>> >>>> On 21 Dec 2016, at 12:50, phil(a)highoctane.be wrote: >>>> >>>> Sven, >>>> >>>> I am currently working with IoT and MQTT is necessary. At this point I use mosquitto as the broker and your Pharo client is nice to have and I will test it and give you feedback. >>> >>> That is good to here, Phil. >>> >>> Yes, such real world testing is much needed. This is actually quite fun stuff to experiment with. Let me know how it goes. >>> >>> Sven >>> >>>> I've got a working microPython codebase so can compare what is in there (this for the LoPy device): >>>> >>>> Thx for the module! >>>> >>>> Phil >>>> >>>> On Wed, Dec 21, 2016 at 12:15 PM, Sven Van Caekenberghe <sven(a)stfx.eu> wrote: >>>> Hi, >>>> >>>> MQTT is a light-weight publish/subscribe messaging protocol, originally created around 1998. It is now an official open industry ISO standard. It is perfect for large-scale Internet of Things applications and high performance mobile messaging. >>>> >>>> The publish/subscribe messaging pattern requires a message broker. The broker is responsible for distributing messages to interested clients based on the topic of a message. Parties communicating with each other over MQTT would all be clients in different roles, like producers and consumers, using the broker as middleware. >>>> >>>> Many client libraries for different programming languages and multiple brokers/servers are available. Facebook Messenger and Amazon AWS IOT are two users, among many others. >>>> >>>> >>>> A good client library for Pharo was not yet available. I started a new MQTT project and I am looking for collaborators to help me finish it. The official specification is quite readable and there is a lot of information available (see the References/Links section at the end). >>>> >>>> >>>> Right now, a first version of the following features is available: >>>> >>>> - reading & writing of all 14 binary packet types >>>> >>>> - an experimental client with support for connection open/close, ping, subscribe/unsubscribe, QoS levels 0 (at most once), 1 (at least once) and 2 (exactly once) for application (publish) messages in both directions, message/package IDs and keep alive (heartbeat) >>>> >>>> - unit tests, for packet reading/writing and for clients against 3 publicly available sandbox/test brokers >>>> >>>> Basically, the code works but needs polishing and maturing. Also, it might be useful to experiment with alternative client API design. Not all features are yet implemented. It would also be nice to implement an actual server/broker, not to replace production quality servers, but as a proof of concept and tools during development. >>>> >>>> >>>> Code >>>> >>>> http://smalltalkhub.com/#!/~SvenVanCaekenberghe/MQTT/ >>>> >>>> Right now, documentation is limited, but there are class comments and the most important public API methods are commented too. There is no Metacello configuration yet, just load the 3 packages. >>>> >>>> >>>> References/Links >>>> >>>> - http://mqtt.org >>>> - https://en.wikipedia.org/wiki/MQTT >>>> - http://docs.oasis-open.org/mqtt/mqtt/v3.1.1/os/mqtt-v3.1.1-os.html >>>> - https://github.com/mqtt/mqtt.github.io/wiki/software >>>> - http://mosquitto.org >>>> - https://github.com/emqtt/emqttd >>>> - http://kamilfb.github.io/mqtt-spy/ >>>> - https://github.com/eclipse/paho.mqtt-spy/wiki >>>> - https://eclipse.org/paho/ >>>> - https://eclipse.org/paho/clients/c/embedded/ >>>> - http://www.rabbitmq.com/mqtt.html >>>> - https://vernemq.com >>>> - https://www.ibm.com/developerworks/community/blogs/c565c720-fe84-4f63-873f-… >>>> >>>> >>>> Sandbox/test Servers/Brokers >>>> >>>> iot.eclipse.org:1883 >>>> test.mosquitto.org:1883 >>>> broker.mqtt-dashboard.com:1883 >>>> >>>> >>>> Sven >>>> >>>> -- >>>> Sven Van Caekenberghe >>>> http://stfx.eu >>>> Smalltalk is the Red Pill >>>> >>>> >>>> >>> >>> >>> >> >> >

Dec. 21, 2016

Re: [Pharo-dev] MQTT for Pharo

by Sven Van Caekenberghe

> On 21 Dec 2016, at 16:04, Henrik Johansen <henrik.s.johansen(a)veloxit.no> wrote: > >> >> On 21 Dec 2016, at 14:57 , Sven Van Caekenberghe <sven(a)stfx.eu> wrote: >> >> Hendrik, >> >> Thank you for this detailed feedback. >> >>> On 21 Dec 2016, at 12:44, Henrik Johansen <henrik.s.johansen(a)veloxit.no> wrote: >>> >>> Hi Sven! >>> One thing I noticed when testing the RabbitMQ client with keepalive > 0, was connection being closed and all subscriptions lost when receiving large payloads, due to timeout before the keepalive packet could be sent before waiting to receive next object. >> >> Indeed, I used my Stamp (STOMP) Rabbit MQ client as a model for the MQTT one - there is a lot of similarity, especially in concept. >> >> Keep alive processing is not that easy. I tried to do it by using read timeouts as a source of regular opportunities to check for the need to process keep alive logic. But of course, if you have no outstanding read (in a loop), that won't work. >> >> The fact that receiving a large payload would trigger an actual keep alive time out is not something that I have seen myself. It seems weird that the reading/transferring of incoming data would not count as activity against keep alive, no ? > > I never had a chance to investigate fully, but I distinctly remember having the same reaction! > It's quite awhile ago now, so my memory might be hazy, take the following with an appropriate amount of grains of salt. > > The first times I encountered it, it seemed quite random, occuring after extended periods of client inactivity after receiving only small payloads... > Setting a much shorter keepalive timeout than the default was/is very useful in reproducing/verifying if it is an issue. > The timeouts then occurred relatively shortly after I'd received a single payload with no other activity, and disappeared once I removed the resetting of lastActivity timestamp on reads, indicating that for at least rabbitmq (3.5 was the version at the time, I believe), receiving data was *not* being counted as keep-alive activity. > > The issue of receiving large payloads blocking writing in time was still unresolved, consistently cut off in the middle of (its own!) multi-MB payload transfers due to keepalive packet not being sent. > I couldn't see a solution other than abandoning the elegant single-threaded approach and do keepalive as a separate high-priority process, but the architectural choice for the app changed at this point to not include a MQ in first delivery, so the more involved rewrite for doing so before deploying in production, kinda got stranded :/ Instinctively it feels like messaging and multi-MB payloads would not be a good fit, at least I would suspect that they are an edge case. But maybe I am wrong. I think that the code in StampMedium>>#readBodyBytes: and StampMedium>>#readBodyString: could be refactored to use a loop with chunk buffers and at the same time check the elapsed time to fire back keep alive pings if necessary. A ping too much would not hurt, better safe than sorry. But is is hard to catch any/all network slowdowns, any IO operation could hang/timeout. But all this would assume that the problematic situation can be recreated. > Cheers, > Henry

Dec. 21, 2016

Re: [Pharo-dev] [Vm-dev] Problem with OSSubprocess / signals / heartbeat ?

by Guille Polito

Ok, so following a bit on this. I'll summarize some of our findings, some of them maybe obvious for some people in this list. I saw that there are actually two different kind of VMs for *nix [1] : - threaded heartbeat - itimer + signal heartbeat Specially, I'd like to cite the following paragraph for the lazy: A distinction on linux is between VMs with an itimer hearbeat or a threaded heartbeat. VMs with an itimer hearbeat use setitimer to deliver a SIGALRM signal at regular intervals to interrupt the VM to check for events. These signals can be troublesome, interrupting foreign code that cannot cope with such signals. VMs with a threaded heartbeat use a high-priority thread that loops, blocking on nanosleep and then interrupting the VM, performing the same function as the itimer heartbeat but without using signals. These VMs are to be preferred but suport for multiple thread priorities in user-level processes has only been available on linux in kernels later than 2.6.12. So, I downloaded the heartbeat squeak VM from bintray [2]. This VM requires so deploy some configuration files in /etc/security [2]. Under this configuration OSSubprocess worked like a charm (or I did not found the issue again so far). Now, this heartbeat threaded VM is the recommended in the README file, and we see that OSSubprocess generates the exact issue stated. The main problem remains for the moment since Pharo's default download includes not this VM but the itimer one. I talked with Esteban about it and he was aware of these two VM flavours, and the reason why we are using the itimer one is the need to deploy those permission files in /etc, which makes installation a bit less automatic. Cheers, Guille [1] https://github.com/OpenSmalltalk/opensmalltalk-vm/blob/e17db79411cfec767e04… [2] https://bintray.com/opensmalltalk/vm/download_file?file_path=cog_linux32x86… [3] https://github.com/OpenSmalltalk/opensmalltalk-vm/releases/tag/r3732#linux -------- Original Message -------- > > >> I asked Santa an OSSubprocess that won't hang :) >> > > > I really appreciate to see such not so small polar elfves helping santa :) > > > > Stef > > > > > > > >> Thanks, >> >> Guille >> >> >> >> >> >> -------- Original Message -------- >> >>> >>> >>>> On 19 Dec 2016, at 14:41, Mariano Martinez Peck >>>> <marianopeck(a)gmail.com> wrote: >>>> >>>> >>>> >>>> Hi guys, >>>> >>>> >>>> >>>> Guille Polito kept one of these images if someone can give us a >>>> hand. He also proposed the great idea of using `strace` to see what >>>> was going on. He (together with Pable Tesone) suspected that the >>>> heartbeat could be interrupting the `clone()` function which is (I >>>> think) called internally by the 'posix_spawn()' which is the one >>>> used by OSSubprocess. >>>> >>>> >>>> >>>> When these images are "hung" they found at a infinitive loop like this: >>>> >>> Okay, how many child processes do you have at that point? How many >>> processes does the system have? >>> >>> >>> >>> >>> >>>> [pid 17477] --- SIGALRM {si_signo=SIGALRM, si_code=SI_KERNEL} --- >>>> >>>> [pid 17477] gettimeofday({1482152630, 593498}, NULL) = 0 >>>> >>>> [pid 17477] sigreturn() (mask []) = 120 >>>> >>>> [pid 17477] clone(child_stack=0, >>>> flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, >>>> child_tidptr=0xf7578768) = ? ERESTARTNOINTR (To be restarted) >>>> >>>> [pid 17477] --- SIGALRM {si_signo=SIGALRM, si_code=SI_KERNEL} --- >>>> >>>> [pid 17477] gettimeofday({1482152630, 600126}, NULL) = 0 >>>> >>>> [pid 17477] sigreturn() (mask []) = 120 >>>> >>>> [pid 17477] clone(child_stack=0, >>>> flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, >>>> child_tidptr=0xf7578768) = ? ERESTARTNOINTR (To be restarted) >>>> >>> so above.. 7ms between the two gettimeofday calls? Nothing else? Set >>> a breakpoint on clone/fork in gdb and look at the c-stack at this >>> point? Could you strace with timestamps to see how much time is >>> spent? Is the process suspicious in other ways? >>> >>> >>> >>> So yes.. sounds like clone doesn't complete.. the question is why? >>> Is it out of resources? Is something in the VM blocking longer than >>> the heartbeat, is the heartbeat more frequent than expected? >>> >>> >>> >>> >>> >>>> As you can see, there is a SIGALARM involved. It also looks like >>>> the `gettimeofday` is used by the heartbeat ? Could it be that >>>> someone the heartbeat is interrupting the `clone()` ? >>>> >>>> >>>> >>>> Guille also showed me the `strace` output with a regular / working >>>> image: >>>> >>>> >>>> >>>> >>>> >>>> [pid 18647] --- SIGALRM {si_signo=SIGALRM, si_code=SI_KERNEL} --- >>>> >>>> [pid 18647] gettimeofday({1482152829, 481014}, NULL) = 0 >>>> >>>> [pid 18647] sigreturn() (mask []) = -1 EINTR (Interrupted >>>> system call) >>>> >>>> [pid 18647] getitimer(ITIMER_REAL, {it_interval={0, 2000}, >>>> it_value={0, 1917}}) = 0 >>>> >>>> [pid 18647] recvmsg(3, 0xff7b0734, 0) = -1 EAGAIN (Resource >>>> temporarily unavailable) >>>> >>>> [pid 18647] select(4, [3], [], [3], {0, 1000}) = 0 (Timeout) >>>> >>>> [pid 18647] getitimer(ITIMER_REAL, {it_interval={0, 2000}, >>>> it_value={0, 797}}) = 0 >>>> >>>> [pid 18647] recvmsg(3, 0xff7b0734, 0) = -1 EAGAIN (Resource >>>> temporarily unavailable) >>>> >>>> [pid 18647] select(4, [3], [], [3], {0, 1000}) = ? ERESTARTNOHAND >>>> (To be restarted if no handler) >>>> >>>> [pid 18647] --- SIGALRM {si_signo=SIGALRM, si_code=SI_KERNEL} --- >>>> >>>> >>>> >>>> >>>> >>>> Does anyone have any hint here? >>>> >>> Get timestamps in there. How long does it take to fail/end in this >>> situation? >>> >>> >>> >>> holger >>> >>> >>> >>> >>> >>> >>> >>> >>> >>> >>> >> >> >> >> >> >> > > > > > >

Dec. 21, 2016

Re: [Pharo-dev] MQTT for Pharo

by Henrik Johansen

> On 21 Dec 2016, at 14:57 , Sven Van Caekenberghe <sven(a)stfx.eu> wrote: > > Hendrik, > > Thank you for this detailed feedback. > >> On 21 Dec 2016, at 12:44, Henrik Johansen <henrik.s.johansen(a)veloxit.no> wrote: >> >> Hi Sven! >> One thing I noticed when testing the RabbitMQ client with keepalive > 0, was connection being closed and all subscriptions lost when receiving large payloads, due to timeout before the keepalive packet could be sent before waiting to receive next object. > > Indeed, I used my Stamp (STOMP) Rabbit MQ client as a model for the MQTT one - there is a lot of similarity, especially in concept. > > Keep alive processing is not that easy. I tried to do it by using read timeouts as a source of regular opportunities to check for the need to process keep alive logic. But of course, if you have no outstanding read (in a loop), that won't work. > > The fact that receiving a large payload would trigger an actual keep alive time out is not something that I have seen myself. It seems weird that the reading/transferring of incoming data would not count as activity against keep alive, no ? I never had a chance to investigate fully, but I distinctly remember having the same reaction! It's quite awhile ago now, so my memory might be hazy, take the following with an appropriate amount of grains of salt. The first times I encountered it, it seemed quite random, occuring after extended periods of client inactivity after receiving only small payloads... Setting a much shorter keepalive timeout than the default was/is very useful in reproducing/verifying if it is an issue. The timeouts then occurred relatively shortly after I'd received a single payload with no other activity, and disappeared once I removed the resetting of lastActivity timestamp on reads, indicating that for at least rabbitmq (3.5 was the version at the time, I believe), receiving data was *not* being counted as keep-alive activity. The issue of receiving large payloads blocking writing in time was still unresolved, consistently cut off in the middle of (its own!) multi-MB payload transfers due to keepalive packet not being sent. I couldn't see a solution other than abandoning the elegant single-threaded approach and do keepalive as a separate high-priority process, but the architectural choice for the app changed at this point to not include a MQ in first delivery, so the more involved rewrite for doing so before deploying in production, kinda got stranded :/ Cheers, Henry

Dec. 21, 2016

Re: [Pharo-dev] MQTT for Pharo

by Ben Coman

You might like to collaborate with Tim and Craig. http://forum.world.st/Graphing-weather-data-td4927701.html cheers -ben On Wed, Dec 21, 2016 at 10:17 PM, Sven Van Caekenberghe <sven(a)stfx.eu> wrote: > >> On 21 Dec 2016, at 15:11, phil(a)highoctane.be wrote: >> >> FWIW get yourself an account at http://enco.io > > OK, I'll put it on my list of things to look at. > >> The devportal has mqtt endpoints so that we can integrate with that and possibly have some market place solutions offered and running with Pharo. >> >> I have a small EnCoClient class in Pharo that works. Now making the API support more extensive. >> >> Docs: http://docs.enco.io/docs/device-sensor-apis >> >> Phil >> >> On Wed, Dec 21, 2016 at 2:59 PM, Sven Van Caekenberghe <sven(a)stfx.eu> wrote: >> >> > On 21 Dec 2016, at 12:50, phil(a)highoctane.be wrote: >> > >> > Sven, >> > >> > I am currently working with IoT and MQTT is necessary. At this point I use mosquitto as the broker and your Pharo client is nice to have and I will test it and give you feedback. >> >> That is good to here, Phil. >> >> Yes, such real world testing is much needed. This is actually quite fun stuff to experiment with. Let me know how it goes. >> >> Sven >> >> > I've got a working microPython codebase so can compare what is in there (this for the LoPy device): >> > >> > Thx for the module! >> > >> > Phil >> > >> > On Wed, Dec 21, 2016 at 12:15 PM, Sven Van Caekenberghe <sven(a)stfx.eu> wrote: >> > Hi, >> > >> > MQTT is a light-weight publish/subscribe messaging protocol, originally created around 1998. It is now an official open industry ISO standard. It is perfect for large-scale Internet of Things applications and high performance mobile messaging. >> > >> > The publish/subscribe messaging pattern requires a message broker. The broker is responsible for distributing messages to interested clients based on the topic of a message. Parties communicating with each other over MQTT would all be clients in different roles, like producers and consumers, using the broker as middleware. >> > >> > Many client libraries for different programming languages and multiple brokers/servers are available. Facebook Messenger and Amazon AWS IOT are two users, among many others. >> > >> > >> > A good client library for Pharo was not yet available. I started a new MQTT project and I am looking for collaborators to help me finish it. The official specification is quite readable and there is a lot of information available (see the References/Links section at the end). >> > >> > >> > Right now, a first version of the following features is available: >> > >> > - reading & writing of all 14 binary packet types >> > >> > - an experimental client with support for connection open/close, ping, subscribe/unsubscribe, QoS levels 0 (at most once), 1 (at least once) and 2 (exactly once) for application (publish) messages in both directions, message/package IDs and keep alive (heartbeat) >> > >> > - unit tests, for packet reading/writing and for clients against 3 publicly available sandbox/test brokers >> > >> > Basically, the code works but needs polishing and maturing. Also, it might be useful to experiment with alternative client API design. Not all features are yet implemented. It would also be nice to implement an actual server/broker, not to replace production quality servers, but as a proof of concept and tools during development. >> > >> > >> > Code >> > >> > http://smalltalkhub.com/#!/~SvenVanCaekenberghe/MQTT/ >> > >> > Right now, documentation is limited, but there are class comments and the most important public API methods are commented too. There is no Metacello configuration yet, just load the 3 packages. >> > >> > >> > References/Links >> > >> > - http://mqtt.org >> > - https://en.wikipedia.org/wiki/MQTT >> > - http://docs.oasis-open.org/mqtt/mqtt/v3.1.1/os/mqtt-v3.1.1-os.html >> > - https://github.com/mqtt/mqtt.github.io/wiki/software >> > - http://mosquitto.org >> > - https://github.com/emqtt/emqttd >> > - http://kamilfb.github.io/mqtt-spy/ >> > - https://github.com/eclipse/paho.mqtt-spy/wiki >> > - https://eclipse.org/paho/ >> > - https://eclipse.org/paho/clients/c/embedded/ >> > - http://www.rabbitmq.com/mqtt.html >> > - https://vernemq.com >> > - https://www.ibm.com/developerworks/community/blogs/c565c720-fe84-4f63-873f-… >> > >> > >> > Sandbox/test Servers/Brokers >> > >> > iot.eclipse.org:1883 >> > test.mosquitto.org:1883 >> > broker.mqtt-dashboard.com:1883 >> > >> > >> > Sven >> > >> > -- >> > Sven Van Caekenberghe >> > http://stfx.eu >> > Smalltalk is the Red Pill >> > >> > >> > >> >> >> > >

Dec. 21, 2016

Re: [Pharo-dev] MQTT for Pharo

by Sven Van Caekenberghe

> On 21 Dec 2016, at 15:11, phil(a)highoctane.be wrote: > > FWIW get yourself an account at http://enco.io OK, I'll put it on my list of things to look at. > The devportal has mqtt endpoints so that we can integrate with that and possibly have some market place solutions offered and running with Pharo. > > I have a small EnCoClient class in Pharo that works. Now making the API support more extensive. > > Docs: http://docs.enco.io/docs/device-sensor-apis > > Phil > > On Wed, Dec 21, 2016 at 2:59 PM, Sven Van Caekenberghe <sven(a)stfx.eu> wrote: > > > On 21 Dec 2016, at 12:50, phil(a)highoctane.be wrote: > > > > Sven, > > > > I am currently working with IoT and MQTT is necessary. At this point I use mosquitto as the broker and your Pharo client is nice to have and I will test it and give you feedback. > > That is good to here, Phil. > > Yes, such real world testing is much needed. This is actually quite fun stuff to experiment with. Let me know how it goes. > > Sven > > > I've got a working microPython codebase so can compare what is in there (this for the LoPy device): > > > > Thx for the module! > > > > Phil > > > > On Wed, Dec 21, 2016 at 12:15 PM, Sven Van Caekenberghe <sven(a)stfx.eu> wrote: > > Hi, > > > > MQTT is a light-weight publish/subscribe messaging protocol, originally created around 1998. It is now an official open industry ISO standard. It is perfect for large-scale Internet of Things applications and high performance mobile messaging. > > > > The publish/subscribe messaging pattern requires a message broker. The broker is responsible for distributing messages to interested clients based on the topic of a message. Parties communicating with each other over MQTT would all be clients in different roles, like producers and consumers, using the broker as middleware. > > > > Many client libraries for different programming languages and multiple brokers/servers are available. Facebook Messenger and Amazon AWS IOT are two users, among many others. > > > > > > A good client library for Pharo was not yet available. I started a new MQTT project and I am looking for collaborators to help me finish it. The official specification is quite readable and there is a lot of information available (see the References/Links section at the end). > > > > > > Right now, a first version of the following features is available: > > > > - reading & writing of all 14 binary packet types > > > > - an experimental client with support for connection open/close, ping, subscribe/unsubscribe, QoS levels 0 (at most once), 1 (at least once) and 2 (exactly once) for application (publish) messages in both directions, message/package IDs and keep alive (heartbeat) > > > > - unit tests, for packet reading/writing and for clients against 3 publicly available sandbox/test brokers > > > > Basically, the code works but needs polishing and maturing. Also, it might be useful to experiment with alternative client API design. Not all features are yet implemented. It would also be nice to implement an actual server/broker, not to replace production quality servers, but as a proof of concept and tools during development. > > > > > > Code > > > > http://smalltalkhub.com/#!/~SvenVanCaekenberghe/MQTT/ > > > > Right now, documentation is limited, but there are class comments and the most important public API methods are commented too. There is no Metacello configuration yet, just load the 3 packages. > > > > > > References/Links > > > > - http://mqtt.org > > - https://en.wikipedia.org/wiki/MQTT > > - http://docs.oasis-open.org/mqtt/mqtt/v3.1.1/os/mqtt-v3.1.1-os.html > > - https://github.com/mqtt/mqtt.github.io/wiki/software > > - http://mosquitto.org > > - https://github.com/emqtt/emqttd > > - http://kamilfb.github.io/mqtt-spy/ > > - https://github.com/eclipse/paho.mqtt-spy/wiki > > - https://eclipse.org/paho/ > > - https://eclipse.org/paho/clients/c/embedded/ > > - http://www.rabbitmq.com/mqtt.html > > - https://vernemq.com > > - https://www.ibm.com/developerworks/community/blogs/c565c720-fe84-4f63-873f-… > > > > > > Sandbox/test Servers/Brokers > > > > iot.eclipse.org:1883 > > test.mosquitto.org:1883 > > broker.mqtt-dashboard.com:1883 > > > > > > Sven > > > > -- > > Sven Van Caekenberghe > > http://stfx.eu > > Smalltalk is the Red Pill > > > > > > > > >

Dec. 21, 2016

Re: [Pharo-dev] MQTT for Pharo

by phil＠highoctane.be

FWIW get yourself an account at http://enco.io The devportal has mqtt endpoints so that we can integrate with that and possibly have some market place solutions offered and running with Pharo. I have a small EnCoClient class in Pharo that works. Now making the API support more extensive. Docs: http://docs.enco.io/docs/device-sensor-apis Phil On Wed, Dec 21, 2016 at 2:59 PM, Sven Van Caekenberghe <sven(a)stfx.eu> wrote: > > > On 21 Dec 2016, at 12:50, phil(a)highoctane.be wrote: > > > > Sven, > > > > I am currently working with IoT and MQTT is necessary. At this point I > use mosquitto as the broker and your Pharo client is nice to have and I > will test it and give you feedback. > > That is good to here, Phil. > > Yes, such real world testing is much needed. This is actually quite fun > stuff to experiment with. Let me know how it goes. > > Sven > > > I've got a working microPython codebase so can compare what is in there > (this for the LoPy device): > > > > Thx for the module! > > > > Phil > > > > On Wed, Dec 21, 2016 at 12:15 PM, Sven Van Caekenberghe <sven(a)stfx.eu> > wrote: > > Hi, > > > > MQTT is a light-weight publish/subscribe messaging protocol, originally > created around 1998. It is now an official open industry ISO standard. It > is perfect for large-scale Internet of Things applications and high > performance mobile messaging. > > > > The publish/subscribe messaging pattern requires a message broker. The > broker is responsible for distributing messages to interested clients based > on the topic of a message. Parties communicating with each other over MQTT > would all be clients in different roles, like producers and consumers, > using the broker as middleware. > > > > Many client libraries for different programming languages and multiple > brokers/servers are available. Facebook Messenger and Amazon AWS IOT are > two users, among many others. > > > > > > A good client library for Pharo was not yet available. I started a new > MQTT project and I am looking for collaborators to help me finish it. The > official specification is quite readable and there is a lot of information > available (see the References/Links section at the end). > > > > > > Right now, a first version of the following features is available: > > > > - reading & writing of all 14 binary packet types > > > > - an experimental client with support for connection open/close, ping, > subscribe/unsubscribe, QoS levels 0 (at most once), 1 (at least once) and 2 > (exactly once) for application (publish) messages in both directions, > message/package IDs and keep alive (heartbeat) > > > > - unit tests, for packet reading/writing and for clients against 3 > publicly available sandbox/test brokers > > > > Basically, the code works but needs polishing and maturing. Also, it > might be useful to experiment with alternative client API design. Not all > features are yet implemented. It would also be nice to implement an actual > server/broker, not to replace production quality servers, but as a proof of > concept and tools during development. > > > > > > Code > > > > http://smalltalkhub.com/#!/~SvenVanCaekenberghe/MQTT/ > > > > Right now, documentation is limited, but there are class comments and > the most important public API methods are commented too. There is no > Metacello configuration yet, just load the 3 packages. > > > > > > References/Links > > > > - http://mqtt.org > > - https://en.wikipedia.org/wiki/MQTT > > - http://docs.oasis-open.org/mqtt/mqtt/v3.1.1/os/mqtt-v3.1.1-os.html > > - https://github.com/mqtt/mqtt.github.io/wiki/software > > - http://mosquitto.org > > - https://github.com/emqtt/emqttd > > - http://kamilfb.github.io/mqtt-spy/ > > - https://github.com/eclipse/paho.mqtt-spy/wiki > > - https://eclipse.org/paho/ > > - https://eclipse.org/paho/clients/c/embedded/ > > - http://www.rabbitmq.com/mqtt.html > > - https://vernemq.com > > - https://www.ibm.com/developerworks/community/ > blogs/c565c720-fe84-4f63-873f-607d87787327/entry/mqtt_security > > > > > > Sandbox/test Servers/Brokers > > > > iot.eclipse.org:1883 > > test.mosquitto.org:1883 > > broker.mqtt-dashboard.com:1883 > > > > > > Sven > > > > -- > > Sven Van Caekenberghe > > http://stfx.eu > > Smalltalk is the Red Pill > > > > > > > > >

Dec. 21, 2016