this is my code for send request and receive data from rest api. but there is one problem: Sometimes the site responds late. how can i send my request without considering the site's response.

import time

import requests

file = open('save_data.csv', 'w')
url = 'http://127.0.0.1:8000/data'


def retrieve_data():
   try:
       response = requests.get(url)
       file.write(response.text   '\n')
       return True
   except:
       return False


interval = 0.5
while True:
   # add session to retrieve function
   result = retrieve_data()
   # if every thing ok sleep for 0.5 seconds
   if result:
       time.sleep(interval)
   else:
       # if we have any error , sleep for 5 second and continue run
       time.sleep(5)

after search find we have two choice:

1. use Thread
2. use asyncio

what is the best solution and how to do it?

CodePudding user response：

I would go with a thread its simple to use.

import threading

thread = threading.Thread(target=func,args=arguments) #in your case you dont need the arguments

thread.start() #start the thread

i would also consider using a mutex or global bool to ensure that you dont try to write to the file even tho ist used by another thread

You could use something like this :

import time
import threading
import requests

file = open('save_data.csv', 'w')
url = 'http://127.0.0.1:8000/data'
file_is_used = False

def retrieve_data():
    global file_is_used
    try:
        response = requests.get(url)
        while file_is_used:
            time.sleep(0.1)
        file_is_used = True
        file.write(response.text   '\n')
        file_is_used = False
        return True
    except:
        file_is_used = False
        return False


interval = 0.5
while True:
    time.sleep(interval)
    if threading.active_count() >= 10: #allows a maximum of 10 concurrent Threads
        continue
    thread = threading.Thread(target=retrieve_data)
    thread.start()