[zeromq-dev] ZeroMQ with Python and a basic task

[Michael Cuggy]

The repo link had the code that I needed.  Thank you for the solution.
I hope Zeromq.org can update its site.  The technology itself would be
more accessible if the corresponding server version of the Python
script was clearly noted.  I think the comments of both the client and
server versions should indicate that they are each a member of a pair.

On 3/8/15, MinRK <benjaminrk at gmail.com> wrote:
> Hello World is a client + server example. You need to be running the
> hwserver program, described above the link to hwclient in the Guide. The
> Python version *should* be available at
> http://zguide.zeromq.org/py:hwserver,
> but for some reason the hwserver links aren’t in the Guide. You can find it
> in
> the examples repo
> <https://github.com/imatix/zguide/blob/master/examples/Python/hwserver.py>
> in the meantime.
>
> -MinRK
> ​
>
> On Sat, Mar 7, 2015 at 8:47 PM, Michael Cuggy <mcuggy at gmail.com> wrote:
>
>> Hello,
>>
>> "On your example, are you running the requisite request receiver, eg
>> the python script that binds to port 5555 in order that the server can
>> have something to connect to?"
>>
>> Yes, I think so.  Can you help me with this as I seem to have made a
>> mistake?
>>
>> To be honest, I thought it was supposed to run by itself with no other
>> server:
>>
>> http://zguide.zeromq.org/py:hwclient
>>
>> The loop back address in the code snippet above made me think it could
>> be a standalone test.  I have a pair of Linux servers.
>>
>> One server has this:
>> http://pastebin.com/nGc36Dq1
>>
>> A second server has this:
>> http://pastebin.com/EVzCSKMn
>>
>> When I run both, I only see this:
>>
>> Connecting to hello world server...
>> Sending request 0 ...
>>
>> It just hangs forever.  I don't think there is a security restriction
>> preventing the communication.*  But the communication never happens,
>> so I don't know what is wrong.
>>
>> thanks,
>>
>> Mike
>>
>> * I ran an nmap command to test connectivity on port 5555 on both
>> servers.  The results indicate that the port isn't being blocked.  It
>> says "closed" and not "filtered."  Filtered would indicate that the
>> nmap utility's probe was being dropped.  A probe being dropped means
>> that a firewall is blocking connectivity on that port.  This is not
>> the case.  "Closed" indicates a lack of usage but not firewall
>> blockage.
>>
>> I therefore don't understand how to get ZeroMQ working using the
>> Python code on zeromoq.org.
>>
>>
>> On 3/1/15, Kenneth Adam Miller <kennethadammiller at gmail.com> wrote:
>> > On your example, are you running the requisite request receiver, eg the
>> > python script that binds to port 5555 in order that the server can have
>> > something to connect to? Just checking.
>> >
>> > Well it depends on what all you want it to do in what scenario. If
>> > these
>> > are two typical user machines, you might need tcp hole punching to get
>> past
>> > firewalls to start with. There's libraries for that, and I'll probably
>> > go
>> > through that soon for my application.
>> >
>> > Also, you don't have to start from scratch, you could easily work from
>> one
>> > of the plethora of existing messaging clients and extend them, or at
>> least
>> > read their source to see how they work.
>> >
>> > On Mon, Mar 2, 2015 at 12:29 AM, Michael Cuggy <mcuggy at gmail.com>
>> > wrote:
>> >
>> >> Hello,
>> >>
>> >> I am using RHEL v. 7.x on AWS.  I installed ZeroMQ 4.0.5.  I want to
>> >> create a basic program using Python and ZeroMQ that serves as a chat
>> >> service for human users using Linux on a LAN.
>> >>
>> >> I have made a significant effort.  I installed the prerequisites for
>> >> ZeroMQ and ZeroMQ itself. I installed the Python bindings.
>> >>
>> >> The problem is that I cannot even get a Hello World program to work on
>> >> one server.  But I used the Hello World program that was on the
>> >> zeromq.org page. (http://zguide.zeromq.org/py:hwclient)
>> >>
>> >> Here is what I get (after running python hello.py):
>> >>
>> >> "Connecting to hello world server
>> >> Sending request 0"
>> >>
>> >> It pauses indefinitely after this.  I have to escape out with Ctrl-c.
>> >>
>> >> Can I get step-by-step directions on how to create a messaging program
>> >> using Python and Zeromq?  I just want it to work between two Linux
>> >> machines to start with.  It is just problem after problem.  If no one
>> >> knows of such documentation, can someone please tell me why I cannot
>> >> see "Hello World" via the Python program that ZeroMQ.org provides?  To
>> >> me it just
>> >> pauses after "Sending request 0."
>> >>
>> >> thanks,
>> >>
>> >> Mike
>> >> _______________________________________________
>> >> zeromq-dev mailing list
>> >> zeromq-dev at lists.zeromq.org
>> >> http://lists.zeromq.org/mailman/listinfo/zeromq-dev
>> >>
>> >
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