I am developing a sms app for symbian using pys60.
I have created a thread for sending the sms but theread is not working.
I want this thread to run in background, irrespective of applicaton closed or not.
contact index is a dictionary with contact nos and names.
def send_sms(contact_index):
import thread
appuifw.note(u"entered to send sms thread")
tid = thread.start_new_thread(send_sms_thread, (contact_index, ))
appuifw.note(u"completed")
it enters "entered to send sms thread" but doesnt go after that.
the function sens_sms_thread is :
def send_sms_thread(contact_index):
appuifw.note(u"entering the thread in sending sms in loops")
for numbers in contact_index:
name = contact_index[number]
appuifw.note(u"sending sms to %s ." % name)
messaging.sms_send(numbers, message_content, '7bit', cb, '')
e32.ao_sleep(30)
can anyone tell me why it is not entering into this thread which will run in background inrrespective of application closed or not?
Use the threading module. Threads created by this module will be waited on by the main thread before the process exits.
thread = threading.Thread(target=send_sms_thread, args=(contact_index,))
thread.start()
Threads created elsewhere, or with the daemon attribute are not waited for.
Try the next snippet:
if __name__=='__main__':
th = e32.ao_callgate(Udp_recv)
thread.start_new_thread(th,())
for i in range(10):
tmp = (str(i)+data)[0:10]
Udp_recv is the function running in background.
Related
I am trying to figure out how to properly send a CTRL-C signal on Windows using Python. Earlier I was messing around with youtube-dl and embedded it into a PyQt Qthread to do the processing and created a stop button to stop the thread but when trying to download a livestream I was unable to get FFMPEG to stop even after closing the application and I'd have to manually kill the process which breaks the video every time.
I knew I'd have to send it a CTRL-C signal somehow and ended up using this.
os.kill(signal.CTRL_C_EVENT, 0)
I was actually able to get it to work but if you try to download more than one video and try to stop one of the threads with the above signal it would kill all the downloads.
Is there any way to send the signal to just one thread without effecting the others?
Here is an example of some regular Python code with 2 seperate threads where the CTRL-C signal is fired in thread_2 after 10 seconds which ends up killing thread_1.
import os
import signal
import threading
import time
import youtube_dl
def thread_1():
print("thread_1 running")
url = 'https://www.cbsnews.com/common/video/cbsn_header_prod.m3u8'
path = 'C:\\Users\\Richard\\Desktop\\'
ydl_opts = {
'format': 'bestvideo[ext=mp4]+bestaudio[ext=m4a]/best[ext=mp4]/best',
'outtmpl': '{0}%(title)s-%(id)s.%(ext)s'.format(path),
'nopart': True,
}
ydl_opts = ydl_opts
with youtube_dl.YoutubeDL(ydl_opts) as ydl:
try:
ydl.download([url])
except KeyboardInterrupt:
print('stopped')
def thread_2():
print("thread_2 running")
time.sleep(10)
os.kill(signal.CTRL_C_EVENT, 0)
def launch_thread(target, message, args=[], kwargs={}):
def thread_msg(*args, **kwargs):
target(*args, **kwargs)
print(message)
thread = threading.Thread(target=thread_msg, args=args, kwargs=kwargs)
thread.start()
return thread
if __name__ == '__main__':
thread1 = launch_thread(thread_1, "finished thread_1")
thread2 = launch_thread(thread_2, "finished thread_2")
Does anyone have any suggestions or ideas? Thanks.
It is not possible to send signals to another thread, so you need to do something else.
You could possibly raise an exception in another thread, using this hack (for which I won't copy the source here because it comes with an MIT license):
http://tomerfiliba.com/recipes/Thread2/
With that, you could send a KeyboardInterrupt exception to the other thread, which is what happens with Ctrl-C anyway.
While it seems like this would do what you want, it would still break the video which is currently downloading.
On the other hand, since you seem to only be interested in killing all threads when the main thread exits, that can be done in a much simpler way:
Configure all threads as daemons, e.g.:
thread = threading.Thread(target=thread_msg, args=args, kwargs=kwargs)
thread.daemon = True
thread.start()
These threads will exit when the main thread exits, without any additional intervention needed from you.
Is there any way to send the signal to just one thread without effecting the others?
I am not a Python expert, but if I was trying to solve your problem, after reading about signal handling in Python3, I would start planning to use multiple processes instead of using multiple threads within a single process.
You can use signal.pthread_kill
from signal import pthread_kill, SIGTSTP
from threading import Thread
from itertools import count
from time import sleep
def target():
for num in count():
print(num)
sleep(1)
thread = Thread(target=target)
thread.start()
sleep(5)
pthread_kill(thread.ident, SIGTSTP)
result
0
1
2
3
4
[14]+ Stopped
This is a long one.
I have a list of usernames and passwords. For each one I want to login to the accounts and do something things. I want to use several machines to do this faster. The way I was thinking of doing this is have a main machine whose job is just having a cron which from time to time checks if the rabbitmq queue is empty. If it is, read the list of usernames and passwords from a file and send it to the rabbitmq queue. Then have a bunch of machines which are subscribed to that queue whose job is receiving a user/pass, do stuff on it, acknowledge it, and move on to the next one, until the queue is empty and then the main machine fills it up again. So far I think I have everything down.
Now comes my problem. I have checked that the things to be done with each user/passes aren't so intensive and so I could have each machine doing three of them simultaneously using python's threading. In fact for a single machine I have implemented this where I load the user/passes into a python Queue() and then have three threads consume that Queue(). Now I want to do something similar, but instead of consuming from a python Queue(), each thread of each machine should consume from a rabbitmq queue. This is where I'm stuck. To run tests I started by using rabbitmq's tutorial.
send.py:
import pika, sys
connection = pika.BlockingConnection(pika.ConnectionParameters('localhost'))
channel = connection.channel()
channel.queue_declare(queue='hello')
message = ' '.join(sys.argv[1:])
channel.basic_publish(exchange='',
routing_key='hello',
body=message)
connection.close()
worker.py
import time, pika
connection = pika.BlockingConnection(pika.ConnectionParameters('localhost'))
channel = connection.channel()
channel.queue_declare(queue='hello')
def callback(ch, method, properties, body):
print ' [x] received %r' % (body,)
time.sleep( body.count('.') )
ch.basic_ack(delivery_tag = method.delivery_tag)
channel.basic_qos(prefetch_count=1)
channel.basic_consume(callback, queue='hello', no_ack=False)
channel.start_consuming()
For the above you can run two worker.py which will subscribe to the rabbitmq queue and consume as expected.
My threading without rabbitmq is something like this:
runit.py
class Threaded_do_stuff(threading.Thread):
def __init__(self, user_queue):
threading.Thread.__init__(self)
self.user_queue = user_queue
def run(self):
while True:
login = self.user_queue.get()
do_stuff(user=login[0], pass=login[1])
self.user_queue.task_done()
user_queue = Queue.Queue()
for i in range(3):
td = Threaded_do_stuff(user_queue)
td.setDaemon(True)
td.start()
## fill up the queue
for user in list_users:
user_queue.put(user)
## go!
user_queue.join()
This also works as expected: you fill up the queue and have 3 threads subscribe to it. Now what I want to do is something like runit.py but instead of using a python Queue(), using something like worker.py where the queue is actually a rabbitmq queue.
Here's something which I tried and didn't work (and I don't understand why)
rabbitmq_runit.py
import time, threading, pika
class Threaded_worker(threading.Thread):
def callback(self, ch, method, properties, body):
print ' [x] received %r' % (body,)
time.sleep( body.count('.') )
ch.basic_ack(delivery_tag = method.delivery_tag)
def __init__(self):
threading.Thread.__init__(self)
self.connection = pika.BlockingConnection(pika.ConnectionParameters('localhost'))
self.channel = self.connection.channel()
self.channel.queue_declare(queue='hello')
self.channel.basic_qos(prefetch_count=1)
self.channel.basic_consume(self.callback, queue='hello')
def run(self):
print 'start consuming'
self.channel.start_consuming()
for _ in range(3):
print 'launch thread'
td = Threaded_worker()
td.setDaemon(True)
td.start()
I would expect that this launches three threads each of which is blocked by .start_consuming() which just stays there waiting for the rabbitmq queue to send them sometihing. Instead, this program starts, does some prints, and exits. The pattern of the exists is weird too:
launch thread
launch thread
start consuming
launch thread
start consuming
In particular notice there is one "start consuming" missing.
What's going on?
EDIT: One answer I found to a similar question is here
Consuming a rabbitmq message queue with multiple threads (Python Kombu)
and the answer is to "use celery", whatever that means. I don't buy it, I shouldn't need anything remotely as sophisticated as celery. In particular, I'm not trying to set up an RPC and I don't need to read replies from the do_stuff routines.
EDIT 2: The print pattern that I expected would be the following. I do
python send.py first message......
python send.py second message.
python send.py third message.
python send.py fourth message.
and the print pattern would be
launch thread
start consuming
[x] received 'first message......'
launch thread
start consuming
[x] received 'second message.'
launch thread
start consuming
[x] received 'third message.'
[x] received 'fourth message.'
The problem is that you're making the thread daemonic:
td = Threaded_worker()
td.setDaemon(True) # Shouldn't do that.
td.start()
Daemonic threads will be terminated as soon as the main thread exits:
A thread can be flagged as a “daemon thread”. The significance of this
flag is that the entire Python program exits when only daemon threads
are left. The initial value is inherited from the creating thread. The
flag can be set through the daemon property.
Leave out setDaemon(True) and you should see it behave the way you expect.
Also, the pika FAQ has a note about how to use it with threads:
Pika does not have any notion of threading in the code. If you want to
use Pika with threading, make sure you have a Pika connection per
thread, created in that thread. It is not safe to share one Pika
connection across threads.
This suggests you should move everything you're doing in __init__() into run(), so that the connection is created in the same thread you're actually consuming from the queue in.
I've seen many topics about this particular problem but i still can't figure why i'm not catching a SIGINT in my main Thread.
Here is my code:
def connect(self, retry=100):
tries=retry
logging.info('connecting to %s' % self.path)
while True:
try:
self.sp = serial.Serial(self.path, 115200)
self.pileMessage = pilemessage.Pilemessage()
self.pileData = pilemessage.Pilemessage()
self.reception = reception.Reception(self.sp,self.pileMessage,self.pileData)
self.reception.start()
self.collisionlistener = collisionListener.CollisionListener(self)
self.message = messageThread.Message(self.pileMessage,self.collisionlistener)
self.datastreaminglistener = dataStreamingListener.DataStreamingListener(self)
self.datastreaming = dataStreaming.Data(self.pileData,self.datastreaminglistener)
return
except serial.serialutil.SerialException:
logging.info('retrying')
if not retry:
raise SpheroError('failed to connect after %d tries' % (tries-retry))
retry -= 1
def disconnect(self):
self.reception.stop()
self.message.stop()
self.datastreaming.stop()
while not self.pileData.isEmpty():
self.pileData.pop()
self.datastreaminglistener.remove()
while not self.pileMessage.isEmpty():
self.pileMessage.pop()
self.collisionlistener.remove()
self.sp.close()
if __name__ == '__main__':
import time
try:
logging.getLogger().setLevel(logging.DEBUG)
s = Sphero("/dev/rfcomm0")
s.connect()
s.set_motion_timeout(65525)
s.set_rgb(0,255,0)
s.set_back_led_output(255)
s.configure_locator(0,0)
except KeyboardInterrupt:
s.disconnect()
In the main function I call Connect() which is launching Threads over which i don't have direct controll.
When I launch this script I would like to be able to stop it when hitting Control+C by calling the "disconnect()" function which stops all the other threads.
In the code i provided it doesn't work because there is no thread in the main function. But I already tryied putting all the instuctions from Main() in a Thread with a While loop without success.
Is there a simple way to solve my problem ?
Thanx
Your indentation is messed up, but there's enough to go on.
Your main thread isn't catching SIGINT because it's not alive. There is nothing that stops your main thread from continuing past the try block, seeing no more code, and closing up shop.
I am not familiar with Sphero. I just attempted to google its docs and was linked to a bunch of 404 pages, so I'll tell you what you would normally do in a threaded environment - join your threads to the main thread so that the main thread can't finish execution before the worker threads.
for t in my_thread_list:
t.join() #main thread can't get past here until all the threads finish
If your Sphero object doesn't provide join-like functionality, you could hack something in that blocks, i.e.
raw_input('Press Enter to disconnect')
s.disconnect()
For starters, I'm on python 2.7.5 and Windows x64, my app is targeted at those parameters.
I'm in need of a way to cancel a raw_input after a certain amount of time has passed. Currently I have my main thread starting two child threads, one is the timer (threading.Timer) and the other fires the raw_input. These both return a value to a Queue.queue that the main thread monitors. It then acts on what is sent to the queue.
# snip...
q = Queue.queue()
# spawn user thread
user = threading.Thread(target=user_input, args=[q])
# spawn timer thread (20 minutes)
timer = threading.Timer(1200, q.put, ['y'])
# wait until we get a response from either
while q.empty():
time.sleep(1)
timer.cancel()
# stop the user input thread here if it's still going
# process the queue value
i = q.get()
if i in 'yY':
# do yes stuff here
elif i in 'nN':
# do no stuff here
# ...snip
def user_input(q):
i = raw_input(
"Unable to connect in last {} tries, "
"do you wish to continue trying to "
"reconnect? (y/n)".format(connect_retries))
q.put(i)
The research that I've done so far seems to say that it's not possible to "correctly" cancel a thread. I feel that processes are too heavy for the task, though I'm not opposed to using them if that's what really needs to be done. Instead, my thought is that if the timer finishes with no user input, I can write a value to stdin and close that thread gracefully.
So, how do I write to stdin from the main thread so that the child thread accepts the input and closes gracefully?
Thanks!
You can use the threading.Thread.join method to handle the timeout. The key to getting it working is to set the daemon attribute as shown below.
import threading
response = None
def get_response():
global response
response = input("Do you wish to reconnect? ")
thread = threading.Thread(target=get_response, daemon=True)
thread.start()
thread.join(2)
if response is None:
print()
print('Exiting')
else:
print('As you wish')
I'm starting out with DBus and event driven programming in general. The service that I'm trying to create really consists of three parts but two are really "server" things.
1) The actual DBus server talks to a remote website over HTTPS, manages sessions, and conveys info the clients.
2) The other part of the service calls a keep alive page every 2 minutes to keep the session active on the external website
3) The clients make calls to the service to retrieve info from the service.
I found some simple example programs. I'm trying to adapt them to prototype #1 and #2. Rather than building separate programs for both. I thought I that I can run them in a single, two threaded process.
The problem that I'm seeing is that I call time.sleep(X) in my keep alive thread. The thread goes to sleep, but won't ever wake up. I think that the GIL isn't released by the GLib main loop.
Here's my thread code:
class Keepalive(threading.Thread):
def __init__(self, interval=60):
super(Keepalive, self).__init__()
self.interval = interval
bus = dbus.SessionBus()
self.remote = bus.get_object("com.example.SampleService", "/SomeObject")
def run(self):
while True:
print('sleep %i' % self.interval)
time.sleep(self.interval)
print('sleep done')
reply_status = self.remote.keepalive()
if reply_status:
print('Keepalive: Success')
else:
print('Keepalive: Failure')
From the print statements, I know that the sleep starts, but I never see "sleep done."
Here is the main code:
if __name__ == '__main__':
try:
dbus.mainloop.glib.DBusGMainLoop(set_as_default=True)
session_bus = dbus.SessionBus()
name = dbus.service.BusName("com.example.SampleService", session_bus)
object = SomeObject(session_bus, '/SomeObject')
mainloop = gobject.MainLoop()
ka = Keepalive(15)
ka.start()
print('Begin main loop')
mainloop.run()
except Exception as e:
print(e)
finally:
ka.join()
Some other observations:
I see the "begin main loop" message, so I know it's getting control. Then, I see "sleep %i," and after that, nothing.
If I ^C, then I see "sleep done." After ~20 seconds, I get an exception from self.run() that the remote application didn't respond:
DBusException: org.freedesktop.DBus.Error.NoReply: Did not receive a reply. Possible causes include: the remote application did not send a reply, the message bus security policy blocked the reply, the reply timeout expired, or the network connection was broken.
What's the best way to run my keep alive code within the server?
Thanks,
You have to explicitly enable multithreading when using gobject by calling gobject.threads_init(). See the PyGTK FAQ for background info.
Next to that, for the purpose you're describing, timeouts seem to be a better fit. Use as follows:
# Enable timer
self.timer = gobject.timeout_add(time_in_ms, self.remote.keepalive)
# Disable timer
gobject.source_remove(self.timer)
This calls the keepalive function every time_in_ms (milli)seconds. Further details, again, can be found at the PyGTK reference.