Python 2.7: import Module and function and assign variable to new variable

Question

I'm already struggeling some hours with a problem within my python project.

The situation is as follows:

I have a script A.py and a Script B.py

**Script A.py:**
#in this script the function def main() is running 

def main():

       #some coding in here

       x=str(body)#then i assign the string of the variable body to a new variable x

#some other coding in here

if __name__=='__main__':

        main()

REMIND: this a pseudo code to explain my struggle (the script as a standalone module is working properly) !

Now I have Script B.py (in the same folder)

**Script B.py** #in this script i try to run Script A.py and assign the value of variable x to a new variable in order to do furhter processing with it.

import A

A.main() # When importing the module and excuting its main() function by running B.py I see the values of variable x appearing on my screen

QUESTION: How can I assign the value of variable x now to a new variable so that i can do further processing with it in B.py ? Is this even possible ? Cause after calling the main function of A.py no other operations are processed.

Please consider that I'm a relatively newby regaring programming over several modules.

I would be very glad for any help.

Thank you very much in advance

Kind regards

Slin

---

Ok i tried your approaches but still not getting the desired result.

A.py is a AMQP subscribing script (https://www.rabbitmq.com/tutorials/tutorial-one-python.html) (see below):

import pika



   credentials = pika.PlainCredentials('admin', 'admin')
   connection = pika.BlockingConnection(pika.ConnectionParameters('Ipaddress',
                                          5672,
                                          '/',
                                          credentials))
   #connection = pika.BlockingConnection(pika.ConnectionParameters(host='localhost'))
   channel = connection.channel()

   channel.exchange_declare(exchange='logs',
                               exchange_type='fanout')

   result = channel.queue_declare(exclusive=True)
   queue_name = result.method.queue

   channel.queue_bind(exchange='logs',
                         queue=queue_name)

   print(' [*] Waiting for logs. To exit press CTRL+C')

   def callback(ch, method, properties, body):

          x = str(body)
          print str(x)
   channel.basic_consume(callback,
                            queue=queue_name,
                            no_ack=True)



   channel.start_consuming()


if __name__ == '__main__':
       main()

B.py:

import pika
import A
A.main()

With the approaches so far i get the same as shown with the coding above. I would like to assign x (which values can chane when A is running) to a new variable within B.py to do some processing to publish it afterwards with the counterpart script of A.py.

When executing B.py i receive:

[*] Waiting for logs. To exit press CTRL+C
['20'] #this is the string of variable x from script A

Now i want to assign this ['20'] to a new variable wihtin B.py.. but the script B.py keeps running A.main() (which is logical cause it is a loop).

Thanks so far for your support.

Kind regards

Answer 1

You could return the value of x to script B using the return statement:

return str(body)#then i assign the string of the variable body to a new variable x

Then get this value in script B by storing it in a variable x = A.main().

Answer 2

Just treat it like you do with any other module. In script A, create a function as you have called main. In it you have to have a variable that you can insert from the other script, call it body.

Script A:

def main(body):
    ...
    return x

Next you import the other script like you would any other model, using import _.py as _. The you use the function as you would in the other script, B. It is as if you are importing an object A and calling its method b.

Script B:

import a.py as A

object = A.main(thing2string) # or object = A.main() if the script b has something to return

Now you have the object that is created in A from that you can process in be. For example,

processed = [object[i] for i in object]
# ... processing steps

I don't know if you can have it notify you on change. But you use a timer to check if the value is updated and use an if statement to update if it has.

Summary:

You have to add the return line in script A. And you have to set a variable equal to it in script b. This new variable then becomes whatever b returns.

Answer 3

Make x as a global variable inside A.py

**Script A.py:**
#in this script the function def main() is running 

x = ''
def main():
   global x
   #some coding in here

   x=str(body)
   #then i assign the string of the variable body to a new variable x

   if __name__=='__main__':
      main()

Now you can access that x from B.py as A.x