[rabbitmq-discuss] Searching for a client library/example: Problems getting a reliable connection in Python and Erlang

[Daniel Neugebauer]

Hi!

I wanted to use RabbitMQ for simple log collection but for some reason I
can't find any useful AMQP client library (and what good is a server
without a working client?). I'd like to implement in either Python or
Erlang but I'm unable to get a reliable connection - either connection
setup fails, strange error messages appear after a short uptime or the
client just cannot handle connection loss.

What I've written so far is a simple Python script that takes lines from
stdin, builds a dictionary from it and tries to send it via amqplib,
Pika or Kombu (which seems to decide on using amqplib internally). It's
nothing special, I already have a serialized string, that's all I need
to send.

However, Pika or amqplib (it's been a while since I tried them, so I
don't remember which one it was) appeared to have some buffer issue -
although the connection (to localhost) was still alive, I would get
error messages about messages queueing up in the client after a few
minutes. The other library would loose connection a few seconds after
connecting but doesn't notice. Kombu terminates when the connection to
RabbitMQ is lost, although I would expect Kombu to retry since I set
retry = True when calling publish on the Producer object. I'm already
running a reconnect in a loop with a try/except inside but my script
just terminates. Strange...

I also tried to use amqp_client in Erlang but failed to get any
connection (I always get unknown_host unless I enter nothing as host
name). I should add that I only read into Erlang theoretically so far
and didn't get to write much but example programs yet, so it's likely I
do something wrong here (yes, I already tried both binary lists and
regular lists, no difference; I even tried supplying IP addresses in
various forms - without success). Documentation is scarce and what I
found suggests that I'm doing nothing wrong. I would prefer staying with
Python for this implementatin anyway, just thought the client that comes
with RabbitMQ should be able to work fine - unfortunately I seem to be
wrong here. :(

My question is: Does anyone have a complete working example of a
*reliable* client in Python (or Erlang)? Maybe I'm too stupid to read
the (very brief?) documentation correctly or the libraries I tried so
far are just too buggy... What I started with was an example from
"RabbitMQ in Action" but even that didn't work as expected.

If it wasn't for getting logs piped in on the console I would try Java
clients instead as I expect them to be more mature - to me, the Python
libraries appear to be a bit messy, pardon my (maybe wrong) impression
but I'm starting to get very frustrated with this: I've never had more
problems to just get a simple plain string handed over to some other
system. All in all I've spent too many hours in trying to get anything
working and nothing has worked so far.

Thanks,
Daniel