I am trying to connect with IB Api to download some historical data. I have noticed that my client connects to the API, but then disconnects automatically in a very small period (~a few seconds).
Here's the log in the server:
socket connection for client{10} has closed.
Connection terminated.
Here's my main code for starting the app:
class TestApp(TestWrapper, TestClient):
def __init__(self):
TestWrapper.__init__(self)
TestClient.__init__(self, wrapper=self)
self.connect(config.ib_hostname, config.ib_port, config.ib_session_id)
self.session_id = int(config.ib_session_id)
self.thread = Thread(target = self.run)
self.thread.start()
setattr(self, "_thread", self.thread)
self.init_error()
def reset_connection(self):
pass
def check_contract(self, name, exchange_name, security_type, currency):
self.reset_connection()
ibcontract = IBcontract()
ibcontract.secType = security_type
ibcontract.symbol = name
ibcontract.exchange = exchange_name
ibcontract.currency = currency
return self.resolve_ib_contract(ibcontract)
def resolve_contract(self, security):
self.reset_connection()
ibcontract = IBcontract()
ibcontract.secType = security.security_type()
ibcontract.symbol=security.name()
ibcontract.exchange=security.exchange()
ibcontract.currency = security.currency()
return self.resolve_ib_contract(ibcontract)
def get_historical_data(self, security, duration, bar_size, what_to_show):
self.reset_connection()
resolved_ibcontract=self.resolve_contract(security)
data = test_app.get_IB_historical_data(resolved_ibcontract.contract, duration, bar_size, what_to_show)
return data
def create_app():
test_app = TestApp()
return test_app
Any suggestions on what could be the problem? I can show more error messages from the debug if needed.
If you can connect without issue only by changing the client ID, typically that indicates that the previous connection was not properly closed and TWS thinks its still open. To disconnect an API client you should call the EClient.disconnect function explicity, overridden in your example as:
test_app.disconnect()
Though its not necessary to disconnect/reconnect after every task, and you can just leave the connection open for extended periods.
You may sometimes encounter problems if an API function, such as reqHistoricalData, is called immediately after connection. Its best to have a small pause after initiating a connection to wait for a callback such as nextValidID to ensure the connection is complete before proceeding.
http://interactivebrokers.github.io/tws-api/connection.html#connect
I'm not sure what the function init_error() is intended for in your example since it would always be called when a TestApp object is created (whether or not there is an error).
Installing the latest version of TWS API (v 9.76) solved the problem.
https://interactivebrokers.github.io/#
Related
I have this running in a simple python script that runs a http server, its supposed to retrieve data from a post call from my utility company, ive noticed though that as soon as i run it, and navigate to https://www.yougetsignal.com/tools/open-ports/ and check if my port is open for 443, it says closed (even though its open before)
i put this in a test.py and run it so i can wait for the post request and download the xml data, but for whatever it turns off my port when i go and check it
from pgesmd_self_access.api import SelfAccessApi
from pgesmd_self_access.server import SelfAccessServer
from pgesmd_self_access.helpers import save_espi_xml
pge_api = SelfAccessApi.auth( < i changed this to reflect my auth file > )
SelfAccessServer(pge_api, save_file=save_espi_xml)
i thought the port should stay open on my router? it doesnt seem like normal behavior
i think i need to implement SO_REUSEADDR in his code according to some docket documentation, but im not sure how to do that
class SelfAccessServer:
"""Server class for PGE SMD Self Access API."""
def __init__(
self, api_instance, save_file=None, filename=None, to_db=True, close_after=False
):
"""Initialize and start the server on construction."""
PgePostHandler.api = api_instance
PgePostHandler.save_file = save_file
PgePostHandler.filename = filename
PgePostHandler.to_db = to_db
server = HTTPServer(("", 7999), PgePostHandler)
server.socket = ssl.wrap_socket(
server.socket,
certfile=api_instance.cert[0],
keyfile=api_instance.cert[1],
server_side=True,
)
if close_after:
server.handle_request()
else:
server.serve_forever()
I am using python v3.5 with the package spyne 2.13 running on a gunicorn server v19.9
I wrote a small SOAP Webservice with python spyne (working well). It takes a string and enqueues it to rabbitmq. It must not neccessarily be rabbitmq, but also a simple DB insert oslt. Right now it works fine, but each time the webservice is called, it
opens a rabbitmq connection (or a DB connection if you'd like)
sends the message
closes the connection again(?)
I'd like to somehow preserve the connection in some sort of 'instance variable' and re-use it everytime the Webservice gets called. So that it connects only once and not everytime i call the ws. Unfortunately spyne does not seem to create any objects, so there are no instance variables.
Generally: How can I preserve a state (DB or RabbitMQ Connection) when using spyne?
So I tried this Trick with static class properties like so:
class Ws2RabbitMQ(ServiceBase):
rabbit_connection = pika.BlockingConnection(
pika.ConnectionParameters(host='localhost'))
rabbit_channel = rabbit_connection.channel()
#staticmethod
def connectRabbit():
rabbit_cred = pika.PlainCredentials(username='...', password='...')
Ws2RabbitMQ.rabbit_connection = pika.BlockingConnection(pika.ConnectionParameters(
host='...', virtual_host='...', credentials=rabbit_cred))
Ws2RabbitMQ.rabbit_channel = Ws2RabbitMQ.rabbit_connection.channel()
print('Rabbit connected!')
#rpc(AnyXml, _returns=Unicode)
def exportGRID(ctx, payload):
try:
if not Ws2RabbitMQ.rabbit_connection.is_open:
print('RabbitMQ Connection lost - reconnecting...')
Ws2RabbitMQ.connectRabbit()
except Exception as e:
print('RabbitMQ Connection not found - initiating...')
Ws2RabbitMQ.connectRabbit()
Ws2RabbitMQ.rabbit_channel.basic_publish(
exchange='ws2rabbitmq', routing_key="blind", body=payload)
print(" [x] Sent")
return 'OK'
When I call the webservice twice, it works. Now, the Connection is created only once and kept in the Singleton Property.
Here is the scripts output:
RabbitMQ Connection not found - initiating...
Rabbit connected!
[x] Sent
[x] Sent
Briefing
I am currently building a python SMTP Mail sender program.
I added a feature so that the user would not be able to log in if there was no active internet connection, I tried many solutions/variations to make the real time connection checking as swift as possible, there were many problems such as:
The thread where the connection handler was running suddenly lagged when I pulled out the ethernet cable ( to test how it would handle the sudden disconnect )
The whole program crashed
It took several seconds for the program to detect the change
My current solution
I set up a data handling class which would contain all the necessary info ( the modules needed to share info effectively )
import smtplib
from socket import gaierror, timeout
class DataHandler:
is_logged_in = None
is_connected = None
server_conn = None
user_address = ''
user_passwd = ''
#staticmethod
def try_connect():
try:
DataHandler.server_conn = smtplib.SMTP('smtp.gmail.com', 587, timeout=1) # The place where the connection is checked
DataHandler.is_connected = True
except (smtplib.SMTPException, gaierror, timeout):
DataHandler.is_connected = False # Connection status changed upon a connection error
I put a connection handler class on a second thread, the server connection process slowed down the gui when it was all on one thread.
from root_gui import Root
import threading
from time import sleep
from data_handler import DataHandler
def handle_conn():
DataHandler.try_connect()
smtp_client.refresh() # Refreshes the gui according to the current status
def conn_manager(): # Working pretty well
while 'smtp_client' in globals():
sleep(0.6)
try:
handle_conn() # Calls the connection
except NameError: # If the user quits the tkinter gui
break
smtp_client = Root()
handle_conn()
MyConnManager = threading.Thread(target=conn_manager)
MyConnManager.start()
smtp_client.mainloop()
del smtp_client # The connection manager will detect this and stop running
My question is:
Is this a good practice or a terrible waste of resources? Is there a better way to do this because no matter what I tried, this was the only solution that worked.
From what I know the try_connect() function creates a completely new smtp object each time it is run ( which is once in 0.6 seconds! )
Resources/observations
The project on git: https://github.com/cernyd/smtp_client
Observation: the timeout parameter when creating the smtp object improved response times drastically, why is that so?
I am currently doing development on a high performance numeric calculations system that posts it results to a web server. We use flask on a seperate process to serve the web page to keep everything interactive and use websockets to send the data to a JS plotter. The calculations are also split using multiprocessing for performance reasons.
We are currently using Pyro4 to get parameters updated in the calculations from the server. However, if the number of updates per second gets high on our Pyro4 settings object it starts blocking and makes it impossible to update any parameters until we restart the server. The proxy calls are made inside of an async websocket callback.
We are currently not getting any tracebacks, nor exceptions which makes debugging this all tricky. Are there any other people that have a lot of experience with Pyro in this context?
Pyro daemon init code:
Pyro4.config.SERVERTYPE = "multiplex"
daemon = Pyro4.Daemon()
ns = Pyro4.locateNS()
settings = cg.Settings(web_opt, src_opt, rec_opt, det_opt)
uri = daemon.register(settings)
ns.register("cg.settings", uri)
daemon.requestLoop()
Settings class:
class Settings(object):
def __init__(self, web_opt, src_opt, rec_opt, det_opt):
self.pipes = [web_opt, src_opt, rec_opt, det_opt]
def update(self, update):
[pipe.send(update) for pipe in self.pipes]
Proxy call:
def onMessage(self, payload, isBinary):
data = json.loads(payload)
self.factory.content.set_by_uuid(data['id'], data['value'], self.client_address)
settings = Pyro4.Proxy("PYRONAME:cg.settings")
values = self.factory.content.values
settings.update(values)
settings._pyroRelease()
I am working on a web service with Twisted that is responsible for calling up several packages I had previously used on the command line. The routines these packages handle were being prototyped on their own but now are ready to be integrated into our webservice.
In short, I have several different modules that all create a mysql connection property internally in their original command line forms. Take this for example:
class searcher:
def __init__(self,lat,lon,radius):
self.conn = getConnection()[1]
self.con=self.conn.cursor();
self.mgo = getConnection(True)
self.lat = lat
self.lon = lon
self.radius = radius
self.profsinrange()
self.cache = memcache.Client(["173.220.194.84:11211"])
The getConnection function is just a helper that returns a mongo or mysql cursor respectively. Again, this is all prototypical :)
The problem I am experiencing is when implemented as a consistently running server using Twisted's WSGI resource, the sql connection created in init times out, and subsequent requests don't seem to regenerate it. Example code for small server app:
from twisted.web import server
from twisted.web.wsgi import WSGIResource
from twisted.python.threadpool import ThreadPool
from twisted.internet import reactor
from twisted.application import service, strports
import cgi
import gnengine
import nn
wsgiThreadPool = ThreadPool()
wsgiThreadPool.start()
# ensuring that it will be stopped when the reactor shuts down
reactor.addSystemEventTrigger('after', 'shutdown', wsgiThreadPool.stop)
def application(environ, start_response):
start_response('200 OK', [('Content-type','text/plain')])
params = cgi.parse_qs(environ['QUERY_STRING'])
try:
lat = float(params['lat'][0])
lon = float(params['lon'][0])
radius = int(params['radius'][0])
query_terms = params['query']
s = gnengine.searcher(lat,lon,radius)
query_terms = ' '.join( query_terms )
json = s.query(query_terms)
return [json]
except Exception, e:
return [str(e),str(params)]
return ['error']
wsgiAppAsResource = WSGIResource(reactor, wsgiThreadPool, application)
# Hooks for twistd
application = service.Application('Twisted.web.wsgi Hello World Example')
server = strports.service('tcp:8080', server.Site(wsgiAppAsResource))
server.setServiceParent(application)
The first few requests work fine, but after mysqls wait_timeout expires, the dread error 2006 "Mysql has gone away" error surfaces. It had been my understanding that every request to the WSGI Twisted resource would run the application function, thereby regenerating the searcher object and re-leasing the connection. If this isn't the case, how can I make the requests processed as such? Is this kind of Twisted deployment not transactional in this sense? Thanks!
EDIT: Per request, here is the prototype helper function calling up the connection:
def getConnection(mong = False):
if mong == False:
connection = mysql.connect(host = db_host,
user = db_user,
passwd = db_pass,
db = db,
cursorclass=mysql.cursors.DictCursor)
cur = connection.cursor();
return (cur,connection)
else:
return pymongo.Connection('173.220.194.84',27017).gonation_test
i was developing a piece of software with twisted where i had to utilize a constant MySQL database connection. i did run into this problem and digging through the twisted documentation extensively and posting a few questions i was unable to find a proper solution.There is a boolean parameter you can pass when you are instantiating the adbapi.connectionPool class; however it never seemed to work and i kept getting the error irregardless. However, what i am guessing the reconnect boolean represents is the destruction of the connection object when SQL disconnect does occur.
adbapi.ConnectionPool("MySQLdb", cp_reconnect=True, host="", user="", passwd="", db="")
I have not tested this but i will re-post some results when i do or if anyone else has please share.
When i was developing the script i was using twisted 8.2.0 (i havent touched twisted in a while) and back then the framework had no such explicit keep alive method, so i developed a ping/keepalive extension employing event driven paradigm twisted builds upon in conjunction with direct MySQLdb module ping() method (see code comment).
As i was typing this response; however, i did look around the current twisted documentation i was still unable to find an explicit keep-alive method or parameter. My guess is because twisted itself does not have database connectivity libraries/classes. It uses the methods available to python and provides an indirect layer of interfacing with those modules; with some exposure for direct calls to the database library being used. This is accomplished by using the adbapi.runWithConnection method.
here is the module i wrote under twisted 8.2.0 and python 2.6; you can set the intervals between pings. what the script does is, every 20 minutes it pings the database and if it fails, it attempts to reconnect back to it every 60 seconds. I must warn that the script does NOT handle sudden/dropped connection; that you can handle through addErrback whenever you run a query through twisted, atleast thats how i did it. I have noticed that whenever database connection drops, you can only find out if it has when you are executing a query and the event raises an errback, and then at that point you deal with it. Basically, if i dont run a query for 10 minutes, and my database disconnects me, my application will not respond in real time. the application will realize the connection has been dropped when it runs the query that follows; so the database could have disconnected us 1 minute after the first query, 5, 9, etc....
I guess this sort of goes back to the original idea that i have stated, twisted utilizes python's own libraries or 3rd party libraries for database connectivity and because of that, some things are handled a bit differently.
from twisted.enterprise import adbapi
from twisted.internet import reactor, defer, task
class sqlClass:
def __init__(self, db_pointer):
self.dbpool=db_pointer
self.dbping = task.LoopingCall(self.dbping)
self.dbping.start(1200) #20 minutes = 1200 seconds; i found out that if MySQL socket is idled for 20 minutes or longer, MySQL itself disconnects the session for security reasons; i do believe you can change that in the configuration of the database server itself but it may not be recommended.
self.reconnect=False
print "database ping initiated"
def dbping(self):
def ping(conn):
conn.ping() #what happens here is that twisted allows us to access methods from the MySQLdb module that python posesses; i chose to use the native command instead of sending null commands to the database.
pingdb=self.dbpool.runWithConnection(ping)
pingdb.addCallback(self.dbactive)
pingdb.addErrback(self.dbout)
print "pinging database"
def dbactive(self, data):
if data==None and self.reconnect==True:
self.dbping.stop()
self.reconnect=False
self.dbping.start(1200) #20 minutes = 1200 seconds
print "Reconnected to database!"
elif data==None:
print "database is active"
def dbout(self, deferr):
#print deferr
if self.reconnect==False:
self.dbreconnect()
elif self.reconnect==True:
print "Unable to reconnect to database"
print "unable to ping MySQL database!"
def dbreconnect(self, *data):
self.dbping.stop()
self.reconnect=True
#self.dbping = task.LoopingCall(self.dbping)
self.dbping.start(60) #60
if __name__ == "__main__":
db = sqlClass(adbapi.ConnectionPool("MySQLdb", cp_reconnect=True, host="", user="", passwd="", db=""))
reactor.callLater(2, db.dbping)
reactor.run()
let me know how it works out for you :)