I am testing IBM MQ using JMeter and able to establish the connection with queue to send requests over it. However, I need to set "JMS_IBM_LAST_MSG_IN_GROUP" property as true for one of the message but unable to do so. I am using below piece of code while sending request or trying to set the property to true but it remains set to it's default value i.e. false when I am checking in backend. Any clue what I am missing here.
Note: Connection is being established in another sampler and making use of that connection here. This code is working fine to send any request, just that property is not getting set to true.
import java.time.Instant
import com.ibm.msg.client.jms.JmsConstants
def sess = System.getProperties().get("Session")
def destination = System.getProperties().get("Destination")
def producer = sess.createProducer(destination)
def rnd = new Random(System.currentTimeMillis())
def payload = String.format('${groupid}|${sequencenumber}|rest of the payload|')
def msg = sess.createTextMessage(payload)
println('Payload --> ' + payload)
msg.setBooleanProperty(JmsConstants.JMS_IBM_LAST_MSG_IN_GROUP,true)
def start = Instant.now()
producer.send(msg)
def stop = Instant.now()
producer.close()
SampleResult.setResponseData(msg.toString())
SampleResult.setDataType( org.apache.jmeter.samplers.SampleResult.TEXT)
SampleResult.setLatency( stop.toEpochMilli() - start.toEpochMilli())
Your code does not include anything to set the Group ID or sequence number. I assume we have all the relevant code shown, in which case, I think you are missing code something along these lines:
msg.setStringProperty("JMSXGroupID", groupid);
msg.setIntProperty("JMSXGroupSeq", sequencenumber);
As per JMS_IBM_LAST_MSG_IN_GROUP chapter of IBMMQ documentation
This property is ignored in the publish/subscribe domain and is not relevant when an application connects to a service integration bus.
In general it's not necessary to use this property, you can come up with your own custom one, i.e. for the producer:
msg.setBooleanProperty("X_CUSTOM_PROPERTY_LAST_MESSAGE",true)
and for the consumer:
msg.getBooleanProperty("X_CUSTOM_PROPERTY_LAST_MESSAGE")
More information: IBM MQ testing with JMeter - Learn How
Sharing as it might help someone else. Was able to set the property to true by making below changes, rest of the code is same as mentioned in original question
import com.ibm.msg.client.wmq.WMQConstants
def gid=String.format('${groupid}')
def msg = sess.createTextMessage()
println('Payload --> ' + payload)
msg.setStringProperty(WMQConstants.JMSX_GROUPID,gid)
msg.setBooleanProperty(WMQConstants.JMS_IBM_LAST_MSG_IN_GROUP,true)
msg.text=payload
I am a newbie. My current project is when the current end decides to start the modbus service, I will create a process for the modbus service. Then the value is obtained in the parent process, through the ZeroMQ PUB/SUB to pass the value, I now want to update the value of the modbus register in the modbus service process.
I tried the method mentioned by pymodbus provided by updating_server.py, and twisted.internet.task.LoopingCall() to update the value of the register, but this will make it impossible for me to connect to my server with the client. I don't know why?
Use LoopingCall() to establish the server, the log when the client connects.
Then I tried to put both the uploading and startTCPserver in the async loop, but the update was only entered for the first time after the startup, and then it was not entered.
Currently, I'm using the LoopingCall() to handle updates, but I don't think this is a good way.
This is the code I initialized the PUB and all the tags that can read the tag.
from loop import cycle
import asyncio
from multiprocessing import Process
from persistence import models as pmodels
from persistence import service as pservice
from persistence import basic as pbasic
import zmq
from zmq.asyncio import Context
from common import logging
from server.modbustcp import i3ot_tcp as sertcp
import common.config as cfg
import communication.admin as ca
import json
import os
import signal
from datetime import datetime
from server.opcuaserver import i3ot_opc as seropc
async def main():
future = []
task = []
global readers, readers_old, task_flag
logger.debug("connecting to database and create table.")
pmodels.connect_create()
logger.debug("init read all address to create loop task.")
cycle.init_readers(readers)
ctx = Context()
publisher = ctx.socket(zmq.PUB)
logger.debug("init publish [%s].", addrs)
publisher.bind(addrs)
readers_old = readers.copy()
for reader in readers:
task.append(asyncio.ensure_future(
cycle.run_readers(readers[reader], publisher)))
if not len(task):
task_flag = True
logger.debug("task length [%s - %s].", len(task), task)
opcua_server = LocalServer(seropc.opc_server, "opcua")
future = [
start_get_all_address(),
start_api(),
create_address_loop(publisher, task),
modbus_server(),
opcua_server.run()
]
logger.debug("run loop...")
await asyncio.gather(*future)
asyncio.run(main(), debug=False)
This is to get the device tag value and publish it.
async def run_readers(reader, publisher):
while True:
await reader.run(publisher)
class DataReader:
def __init__(self, freq, clients):
self._addresses = []
self._frequency = freq
self._stop_signal = False
self._clients = clients
self.signature = sign_data_reader(self._addresses)
async def run(self, publisher):
while not self._stop_signal:
for addr in self._addresses:
await addr.read()
data = {
"type": "value",
"data": addr._final_value
}
publisher.send_pyobj(data)
if addr._status:
if addr.alarm_log:
return_alarm_log = pbasic.get_log_by_time(addr.alarm_log['date'])
if return_alarm_log:
data = {
"type": "alarm",
"data": return_alarm_log
}
publisher.send_pyobj(data)
self.data_send(addr)
logger.debug("run send data")
await asyncio.sleep(int(self._frequency))
def stop(self):
self._stop_signal = True
modbus server imports
from common import logging
from pymodbus.server.asynchronous import StartTcpServer
from pymodbus.device import ModbusDeviceIdentification
from pymodbus.datastore import ModbusSequentialDataBlock
from pymodbus.datastore import ModbusSlaveContext, ModbusServerContext
from persistence import service as pservice
from persistence import basic as pbasic
import zmq
import common.config as cfg
import struct
import os
import signal
from datetime import datetime
from twisted.internet.task import LoopingCall
def updating_writer(a):
logger.info("in updates of modbus tcp server.")
context = a[0]
# while True:
if check_pid(os.getppid()) is False:
os.kill(os.getpid(), signal.SIGKILL)
url = ("ipc://{}" .format(cfg.get('ipc', 'pubsub')))
logger.debug("connecting to [%s].", url)
ctx = zmq.Context()
subscriber = ctx.socket(zmq.SUB)
subscriber.connect(url)
subscriber.setsockopt(zmq.SUBSCRIBE, b"")
slave_id = 0x00
msg = subscriber.recv_pyobj()
logger.debug("updates.")
if msg['data']['data_type'] in modbus_server_type and msg['type'] == 'value':
addr = pservice.get_mbaddress_to_write_value(msg['data']['id'])
if addr:
logger.debug(
"local address and length [%s - %s].",
addr['local_address'], addr['length'])
values = get_value_by_type(msg['data']['data_type'], msg['data']['final'])
logger.debug("modbus server updates values [%s].", values)
register = get_register(addr['type'])
logger.debug(
"register [%d] local address [%d] and value [%s].",
register, addr['local_address'], values)
context[slave_id].setValues(register, addr['local_address'], values)
# time.sleep(1)
def tcp_server(pid):
logger.info("Get server configure and device's tags.")
st = datetime.now()
data = get_servie_and_all_tags()
if data:
logger.debug("register address space.")
register_address_space(data)
else:
logger.debug("no data to create address space.")
length = register_number()
store = ModbusSlaveContext(
di=ModbusSequentialDataBlock(0, [0] * length),
co=ModbusSequentialDataBlock(0, [0] * length),
hr=ModbusSequentialDataBlock(0, [0] * length),
ir=ModbusSequentialDataBlock(0, [0] * length)
)
context = ModbusServerContext(slaves=store, single=True)
identity = ModbusDeviceIdentification()
identity.VendorName = 'pymodbus'
identity.ProductCode = 'PM'
identity.VendorUrl = 'http://github.com/bashwork/pymodbus/'
identity.ProductName = 'pymodbus Server'
identity.ModelName = 'pymodbus Server'
identity.MajorMinorRevision = '2.2.0'
# ----------------------------------------------------------------------- #
# set loop call and run server
# ----------------------------------------------------------------------- #
try:
logger.debug("thread start.")
loop = LoopingCall(updating_writer, (context, ))
loop.start(1, now=False)
# process = Process(target=updating_writer, args=(context, os.getpid(),))
# process.start()
address = (data['tcp_ip'], int(data['tcp_port']))
nt = datetime.now() - st
logger.info("modbus tcp server begin has used [%s] s.", nt.seconds)
pservice.write_server_status_by_type('modbus', 'running')
StartTcpServer(context, identity=identity, address=address)
except Exception as e:
logger.debug("modbus server start error [%s].", e)
pservice.write_server_status_by_type('modbus', 'closed')
This is the code I created for the modbus process.
def process_stop(p_to_stop):
global ptcp_flag
pid = p_to_stop.pid
os.kill(pid, signal.SIGKILL)
logger.debug("process has closed.")
ptcp_flag = False
def ptcp_create():
global ptcp_flag
pid = os.getpid()
logger.debug("sentry pid [%s].", pid)
ptcp = Process(target=sertcp.tcp_server, args=(pid,))
ptcp_flag = True
return ptcp
async def modbus_server():
logger.debug("get mosbuc server's status.")
global ptcp_flag
name = 'modbus'
while True:
ser = pservice.get_server_status_by_name(name)
if ser['enabled']:
if ser['tcp_status'] == 'closed' or ser['tcp_status'] == 'running':
tags = pbasic.get_tag_by_name(name)
if len(tags):
if ptcp_flag is False:
logger.debug("[%s] status [%s].", ser['tcp_name'], ptcp_flag)
ptcp = ptcp_create()
ptcp.start()
else:
logger.debug("modbus server is running ...")
else:
logger.debug("no address to create [%s] server.", ser['tcp_name'])
pservice.write_server_status_by_type(name, "closed")
else:
logger.debug("[%s] server is running ...", name)
else:
if ptcp_flag:
process_stop(ptcp)
logger.debug("[%s] has been closed.", ser['tcp_name'])
pservice.write_server_status_by_type(name, "closed")
logger.debug("[%s] server not allowed to running.", name)
await asyncio.sleep(5)
This is the command that Docker runs.
/usr/bin/docker run --privileged --network host --name scout-sentry -v /etc/scout.cfg:/etc/scout.cfg -v /var/run:/var/run -v /sys:/sys -v /dev/mem:/dev/mem -v /var/lib/scout:/data --rm shulian/scout-sentry
This is the Docker configuration file /etc/scout.cfg.
[scout]
mode=product
[logging]
level=DEBUG
[db]
path=/data
[ipc]
cs=/var/run/scout-cs.sock
pubsub=/var/run/pubsub.sock
I want to be able to trigger the modbus value update function when there is a message coming from ZeroMQ, and it will be updated correctly.
Let's start from inside out.
Q : ...this will make it impossible for me to connect to my server with the client. I don't know why?
ZeroMQ is a smart broker-less messaging / signaling middleware or better a platform for smart-messaging. In case one feels not so much familiar with the art of Zen-of-Zero as present in ZeroMQ Architecture, one may like to start with ZeroMQ Principles in less than Five Seconds before diving into further details.
The Basis :
The Scalable Formal Communication Archetype, borrowed from ZeroMQ PUB/SUB, does not come at zero-cost.
This means that each infrastructure setup ( both on PUB-side and on SUB-side ) takes some, rather remarkable time and no one can be sure of when the AccessNode cnfiguration results in RTO-state. So the SUB-side (as proposed above) ought be either a permanent entity, or the user shall not expect to make it RTO in zero-time, after a twisted.internet.task.LoopingCall() gets reinstated.
Preferred way: instantiate your (semi-)persistent zmq.Context(), get it configured so as to serve the <aContextInstance>.socket( zmq.PUB ) as needed, a minimum safeguarding setup being the <aSocketInstance>.setsockopt( zmq.LINGER, 0 ) and all transport / queuing / security-handling details, that the exosystem exposes to your code ( whitelisting and secure sizing and resources protection being the most probable candidates - but details are related to your application domain and the risks that you are willing to face being prepared to handle them ).
ZeroMQ strongly discourages from sharing ( zero-sharing ) <aContextInstance>.socket()-instances, yet the zmq.Context()-instance can be shared / re-used (ref. ZeroMQ Principles... ) / passed to more than one threads ( if needed ).
All <aSocketInstance>{.bind()|.connect()}- methods are expensive, so try to setup the infrastructure AccessPoint(s) and their due error-handling way before one tries to use the their-mediated communication services.
Each <aSocketInstance>.setsockopt( zmq.SUBSCRIBE, ... ) is expensive in that it may take ( depending on (local/remote) version ) a form of a non-local, distributed-behaviour - local side "sets" the subscription, yet the remote side has to "be informed" about such state-change and "implements" the operations in line with the actual (propagated) state. While in earlier versions, all messages were dispatched from the PUB-side and all the SUB-side(s) were flooded with such data and were left for "filtering" which will be moved into a local-side internal-Queue, the newer versions "implement" the Topic-Filter on the PUB-side, which further increases the latency of setting the new modus-operandi in action.
Next comes the modus-operandi: how <aSocketInstance>.recv() gets results:
In their default API-state, .recv()-methods are blocking, potentially infinitely blocking, if no messages arrive.
Solution: avoid blocking-forms of calling ZeroMQ <aSocket>.recv()-methods by always using the zmq.NOBLOCK-modes thereof or rather test a presence or absence of any expected-message(s) with <aSocket>.poll( zmq.POLLIN, <timeout> )-methods available, with zero or controlled-timeouts. This makes you the master, who decides about the flow of code-execution. Not doing so, you knowingly let your code depend on external sequence ( or absence ) of events and your architecture is prone to awful problems with handling infinite blocking-states ( or potential unsalvageable many-agents' distributed behaviour live-locks or dead-locks )
Avoid uncontrolled cross-breeding of event-loops - like passing ZeroMQ-driven-loops into an external "callback"-alike handler or async-decorated code-blocks, where the stack of (non-)blocking logics may wreck havoc the original idea just by throwing the system into an unresolvable state, where events miss expected sequence of events and live-locks are unsalvagable or just the first pass happen to go through.
Stacking asyncio-code with twisted-LoopingCall()-s and async/await-decorated code + ZeroMQ blocking .recv()-s is either a Piece-of-Filligrane-Precise-Art-of-Truly-a-Zen-Master, or a sure ticket to Hell - with all respect to the Art-of-Truly-Zen-Masters :o)
So, yes, complex thinking is needed -- welcome to the realms of distributed-computing!
I'm trying to connect two blocks with the "Connector" class implemented in pyomo, using the following simple examplary code.
from pyomo.environ import *
m = ConcreteModel()
# Block 01
m.block_01 = Block()
m.block_01.flow = Var(within=NonNegativeReals, bounds=(2, 10))
m.block_01.OUT = Connector(initialize= {'flow': m.block_01.flow})
# Block 02
m.block_02 = Block()
m.block_02.flow = Var(within=NonNegativeReals)
m.block_02.IN = Connector(initialize= {'flow': m.block_02.flow})
m.con = Constraint(expr=m.block_01.OUT == m.block_02.IN)
def _obj(_m):
return _m.block_01.flow + _m.block_02.flow
m.obj = Objective(rule=_obj)
After "optimization" all variables take their lower bound values (m.block_01.flow = 2 and m.block_02.flow = 0). So the Connector seems not to transfer any data for the variables.
If I'm using:
m.con = Constraint(expr=m.block_01.flow == m.block_02.flow)
instead, it works. However this is not the idea of Connectors, right?
Any ideas about the reason for the problem?
Did you apply the expand_connectors transformation before sending your model to a solver?
TransformationFactory('core.expand_connectors').apply_to(m)
I'm not sure if the title accurately describes what I'm trying to do. I have a Python3.x script that I wrote that will issue flood warning to my facebook page when the river near my home has reached it's lowest flood stage. Right now the script works, however it only reports data from one measuring station. I would like to be able to process the data from all of the stations in my county (total of 5), so I was thinking that maybe a class method may do the trick but I'm not sure how to implement it. I've been teaching myself Python since January and feel pretty comfortable with the language for the most part, and while I have a good idea of how to build a class object I'm not sure how my flow chart should look. Here is the code now:
#!/usr/bin/env python3
'''
Facebook Flood Warning Alert System - this script will post a notification to
to Facebook whenever the Sabine River # Hawkins reaches flood stage (22.3')
'''
import requests
import facebook
from lxml import html
graph = facebook.GraphAPI(access_token='My_Access_Token')
river_url = 'http://water.weather.gov/ahps2/river.php?wfo=SHV&wfoid=18715&riverid=203413&pt%5B%5D=147710&allpoints=143204%2C147710%2C141425%2C144668%2C141750%2C141658%2C141942%2C143491%2C144810%2C143165%2C145368&data%5B%5D=obs'
ref_url = 'http://water.weather.gov/ahps2/river.php?wfo=SHV&wfoid=18715&riverid=203413&pt%5B%5D=147710&allpoints=143204%2C147710%2C141425%2C144668%2C141750%2C141658%2C141942%2C143491%2C144810%2C143165%2C145368&data%5B%5D=all'
def checkflood():
r = requests.get(river_url)
tree = html.fromstring(r.content)
stage = ''.join(tree.xpath('//div[#class="stage_stage_flow"]//text()'))
warn = ''.join(tree.xpath('//div[#class="current_warns_statmnts_ads"]/text()'))
stage_l = stage.split()
level = float(stage_l[2])
#check if we're at flood level
if level < 22.5:
pass
elif level == 37:
major_diff = level - 23.0
major_r = ('The Sabine River near Hawkins, Tx has reached [Major Flood Stage]: #', stage_l[2], 'Ft. ', str(round(major_diff, 2)), ' Ft. \n Please click the link for more information.\n\n Current Warnings and Alerts:\n ', warn)
major_p = ''.join(major_r)
graph.put_object(parent_object='me', connection_name='feed', message = major_p, link = ref_url)
<--snip-->
checkflood()
Each station has different 5 different catagories for flood stage: Action, Flood, Moderate, Major, each different depths per station. So for Sabine river in Hawkins it will be Action - 22', Flood - 24', Moderate - 28', Major - 32'. For the other statinos those depths are different. So I know that I'll have to start out with something like:
class River:
def __init__(self, id, stage):
self.id = id #station ID
self.stage = stage #river level'
#staticmethod
def check_flood(stage):
if stage < 22.5:
pass
elif stage.....
but from there I'm not sure what to do. Where should it be added in(to?) the code, should I write a class to handle the Facebook postings as well, is this even something that needs a class method to handle, is there any way to clean this up for efficiency? I'm not looking for anyone to write this up for me, but some tips and pointers would sure be helpful. Thanks everyone!
EDIT Here is what I figured out and is working:
class River:
name = ""
stage = ""
action = ""
flood = ""
mod = ""
major = ""
warn = ""
def checkflood(self):
if float(self.stage) < float(self.action):
pass
elif float(self.stage) >= float(self.major):
<--snip-->
mineola = River()
mineola.name = stations[0]
mineola.stage = stages[0]
mineola.action = "13.5"
mineola.flood = "14.0"
mineola.mod = "18.0"
mineola.major = "21.0"
mineola.alert = warn[0]
hawkins = River()
hawkins.name = stations[1]
hawkins.stage = stages[1]
hawkins.action = "22.5"
hawkins.flood = "23.0"
hawkins.mod = "32.0"
hawkins.major = "37.0"
hawkins.alert = warn[1]
<--snip-->
So from here I'm tring to stick all the individual river blocks into one block. What I have tried so far is this:
class River:
... name = ""
... stage = ""
... def testcheck(self):
... return self.name, self.stage
...
>>> for n in range(num_river):
... stations[n] = River()
... stations[n].name = stations[n]
... stations[n].stage = stages[n]
...
>>> for n in range(num_river):
... stations[n].testcheck()
...
<__main__.River object at 0x7fbea469bc50> 4.13
<__main__.River object at 0x7fbea46b4748> 20.76
<__main__.River object at 0x7fbea46b4320> 22.13
<__main__.River object at 0x7fbea46b4898> 16.08
So this doesn't give me the printed results that I was expecting. How can I return the string instead of the object? Will I be able to define the Class variables in this manner or will I have to list them out individually? Thanks again!
After reading many, many, many articles and tutorials on class objects I was able to come up with a solution for creating the objects using list elements.
class River():
def __init__(self, river, stage, flood, action):
self.river = river
self.stage = stage
self.action = action
self.flood = flood
self.action = action
def alerts(self):
if float(self.stage < self.flood):
#alert = "The %s is below Flood Stage (%sFt) # %s Ft. \n" % (self.river, self.flood, self.stage)
pass
elif float(self.stage > self.flood):
alert = "The %s has reached Flood Stage(%sFt) # %sFt. Warnings: %s \n" % (self.river, self.flood, self.stage, self.action)
return alert
'''this is the function that I was trying to create
to build the class objects automagically'''
def riverlist():
river_list = []
for n in range(len(rivers)):
station = River(river[n], stages[n], floods[n], warns[n])
river_list.append(station)
return river_list
if __name__ == '__main__':
for x in riverlist():
print(x.alerts())
When configuring watchers, what would be the purpose of including both of these settings under a watching:
singleton = True
numprocess = 1
The documentation states that setting singleton has the following effect:
singleton:
If set to True, this watcher will have at the most one process. Defaults to False.
I read that as negating the need to specify numprocesses however in the github repository they provide an example:
https://github.com/circus-tent/circus/blob/master/examples/example6.ini
Included here as well, where they specify both:
[circus]
check_delay = 5
endpoint = tcp://127.0.0.1:5555
pubsub_endpoint = tcp://127.0.0.1:5556
stats_endpoint = tcp://127.0.0.1:5557
httpd = True
debug = True
httpd_port = 8080
[watcher:swiss]
cmd = ../bin/python
args = -u flask_app.py
warmup_delay = 0
numprocesses = 1
singleton = True
stdout_stream.class = StdoutStream
stderr_stream.class = StdoutStream
So I would assume they do something different and in some way work together?
numprocess is the initial number of process for a given watcher. In the example you provided it is set to 1, but a user can typically add more processes as needed.
singleton would only allow a maxiumum of 1 process running for a given watcher, so it would forbid you from increment the number of processes dynamically.
The code below from circus test suite describes it well ::
#tornado.testing.gen_test
def test_singleton(self):
# yield self._stop_runners()
yield self.start_arbiter(singleton=True, loop=get_ioloop())
cli = AsyncCircusClient(endpoint=self.arbiter.endpoint)
# adding more than one process should fail
yield cli.send_message('incr', name='test')
res = yield cli.send_message('list', name='test')
self.assertEqual(len(res.get('pids')), 1)
yield self.stop_arbiter()