How to post group of requests to 2 urls with aiohttp - python-3.x

I have 2 URLs and 60k+ requests. Basically, I need to post every request to both URLs, then compare their responses, but not to wait for the response to post another request.
I've tried to do it with aiohttp and asyncio
import asyncio
import time
import aiohttp
import os
from aiofile import AIOFile
testURL = ""
prodURL = ""
directoryWithRequests = ''
directoryToWrite = ''
headers = {'content-type': 'application/soap+xml'}
i = 1
async def fetch(session, url, reqeust):
global i
async with session.post(url=url, data=reqeust.encode('utf-8'), headers=headers) as response:
if response.status != 200:
async with AIOFile(directoryToWrite + str(i) + '.xml', 'w') as afp:
await afp.write(reqeust)
i += 1
return await response.text()
async def fetch_all(session, urls, request):
results = await asyncio.gather(*[asyncio.create_task(fetch(session, url, request)) for url in urls])
return results
async def asynchronousRequests(requestBody):
urls = [testURL, prodURL]
global i
with open(requestBody) as my_file:
body = my_file.read()
async with aiohttp.ClientSession() as session:
htmls = await fetch_all(session, urls, body)
# some conditions
async def asynchronous():
try:
start = time.time()
futures = [asynchronousRequests(directoryWithRequests + i) for i in os.listdir(directoryWithRequests)]
for future in asyncio.as_completed(futures):
result = await future
print("Process took: {:.2f} seconds".format(time.time() - start))
except Exception as e:
print(str(e))
if __name__ == '__main__':
try:
# AsyncronTest
ioloop = asyncio.ProactorEventLoop()
ioloop.run_until_complete(asynchronous())
ioloop.close()
if i == 1:
print('Regress is OK')
else:
print('Number of requests to check = {}'.format(i))
except Exception as e:
print(e)
I believe that the code above works, but it creates N futures, where the N equals to the number of request files. This brings to sort of ddos because the server can't response to that number of requests at the same time.

Found suitable solution. Basically it's just 2 async tasks:
tasks = [
postRequest(testURL, client, body),
postRequest(prodURL, client, body)
]
await asyncio.wait(tasks)
It's not the same performance as the code in the question with afortable number of requests, but as least it doesn't ddos the server that much.

Related

using httpx to send 100K get requests

I'm using the httpx library and asyncio to try and send about 100K of get requests.
I ran the code and received httpx.ConnectError so I opened wireshark and saw that I was getting a lot of messages saying TCP Retransmission TCP Port numbers reused
when I saw the data in wireshark and the error httpx.ConnectError I added limits = httpx.Limits(max_connections=10000) to limit the amount of active connections to 10,000 but I still get that error.
my code:
import asyncio
import json
import httpx
SOME_URL = "some url"
ANOTHER_URL = "another url"
MAX = 10000
async def search():
guids = [guid for guid in range(688001, 800000)] # 688001 - 838611
timeout = httpx.Timeout(None)
limits = httpx.Limits(max_connections=MAX)
async with httpx.AsyncClient(timeout=timeout, limits=limits) as client:
tasks = [client.get(f"{SOME_URL}{guid}", timeout=timeout) for guid in guids]
blob_list = await asyncio.gather(*tasks) # <---- error from here !!!!!
blob_list = [(res, guid) for res, guid in zip(blob_list, guids)]
guids = [guid for res, guid in blob_list]
blob_list = [json.loads(res.text)["blob_name"] for res, guid in blob_list]
async with httpx.AsyncClient(timeout=timeout, limits=limits) as client:
tasks = [client.get(f"{ANOTHER_URL}{blob}", timeout=timeout) for blob in blob_list]
game_results = await asyncio.gather(*tasks) # <---- error from here !!!!!
game_results = [(res, guid) for res, guid in zip(game_results, guids)]
game_results = [guid for res, guid in game_results]
print(game_results)
def main():
asyncio.run(search())
if __name__ == '__main__':
main()
this is a minimal version of my code there some steps in between the requests that I deleted, but I didn't touch the code that made the trouble, there are comments on the lines that I receive the errors (# <---- error from here !!!!!).
does anyone know how to solve this? or another way to send about 100K of get requests fast?
I managed to solve my problem with the following code:
(this is not the entire code, only the parts needed to send the requests, I have some stuff in between)
import asyncio
from aiohttp import ClientSession
SOME_URL = "some url"
ANOTHER_URL = "another url"
MAX_SIM_CONNS = 50
worker_responses = []
async def fetch(url, session):
async with session.get(url) as response:
return await response.read()
async def fetch_worker(url_queue: asyncio.Queue):
global worker_responses
async with ClientSession() as session:
while True:
url = await url_queue.get()
try:
if url is None:
return
response = await fetch(url, session)
worker_responses.append(response)
finally:
url_queue.task_done()
# calling task_done() is necessary for the url_queue.join() to work correctly
async def fetch_all(base_url: str, range_: range):
url_queue = asyncio.Queue(maxsize=10000)
worker_tasks = []
for i in range(MAX_SIM_CONNS):
wt = asyncio.create_task(fetch_worker(url_queue))
worker_tasks.append(wt)
for i in range_:
await url_queue.put(f"{base_url}{i}")
for i in range(MAX_SIM_CONNS):
# tell the workers that the work is done
await url_queue.put(None)
await url_queue.join()
await asyncio.gather(*worker_tasks)
if __name__ == '__main__':
asyncio.set_event_loop_policy(asyncio.WindowsSelectorEventLoopPolicy())
asyncio.run(fetch_all(SOME_URL, range(680_842, 840_423)))
print(worker_responses)
I used aiohttp instead of httpx and used asyncio.Queue to reduce RAM usage and it worked for me.

count successful and unsuccessful post requests for asynchronous post call/request

I need help in implementing the logic to count number of successful post calls which are asynchronous in nature (status_code=200) as well as failed_calls (status_code != 200)
I am new to coroutines. Would appreciate if someone can suggest a better way of making a post asynchronous call which can be retried, polled for status, and that can emit metrics for successful post requests as well.
Following is my code:
asyncio.get_event_loop().run_in_executor(
None,
self.publish_actual,
event_name,
custom_payload,
event_message_params,
)
which calls publish_actual:
def publish_actual(
self,
event_name: str,
custom_payload={},
event_message_params=[],
):
"""Submits a post request using the request library
:param event_name: name of the event
:type event_name: str
:param key: key for a particular application
:param custom_payload: custom_payload, defaults to {}
:type custom_payload: dict, optional
:param event_message_params: event_message_params, defaults to []
:type event_message_params: list, optional
"""
json_data = {}
path = f"/some/path"
self.request(path, "POST", json=json_data)
which calls following request function
def request(self, api_path, method="GET", **kwargs):
try:
self._validate_configuration()
headers = {}
api_endpoint = self.service_uri.to_url(api_path)
logger.debug(api_endpoint)
if "headers" in kwargs and kwargs["headers"]:
headers.update(kwargs["headers"])
headers = {"Content-Type": "application/json"}
begin = datetime.now()
def build_success_metrics(response, *args, **kwargs):
tags = {
"name": "success_metrics",
"domain": api_endpoint,
"status_code": 200,
}
build_metrics(tags)
def check_for_errors(response, *args, **kwargs):
response.raise_for_status()
response = self.session.request(
method=method,
url=api_endpoint,
headers=headers,
timeout=self.timeout,
hooks={"response": [build_success_metrics, check_for_errors]},
**kwargs,
)
end = datetime.now()
logger.debug(
f"'{method}' request against endpoint '{api_endpoint}' took {round((end - begin).total_seconds() * 1000, 3)} ms"
)
logger.debug(f"response: {response}")
except RequestException as e:
tags = {
"name": "error_metrics",
"domain": api_endpoint,
"exception_class": e.__class__.__name__,
}
build_metrics(tags)
return f"Exception occured: {e}"
Let me know if anything else is required from my end to explain what exactly I have done and what I am trying to achieve.
There is not much await and async in your example so I've just addressed the counting part of your question in general terms in asyncio. asyncio.Queue is good for this because you can separate out the counting from the cause quite simply.
import asyncio
import aiohttp
class Count():
def __init__(self, queue: asyncio.Queue):
self.queue = queue
self.good = 0
self.bad = 0
async def count(self):
while True:
result = await self.queue.get()
if result == 'Exit':
return
if result == 200:
self.good += 1
else:
self.bad += 1
async def request(q: asyncio.Queue):
async with aiohttp.ClientSession() as session:
for _ in range(5): # just poll 30 times in this instance
await asyncio.sleep(0.1)
async with session.get(
'https://httpbin.org/status/200%2C500', ssl=False
) as response:
q.put_nowait(response.status)
q.put_nowait('Exit')
async def main():
q = asyncio.Queue()
cnt = Count(q)
tasks = [cnt.count(), request(q)]
await asyncio.gather(*[asyncio.create_task(t) for t in tasks])
print(cnt.good, cnt.bad)
if __name__ == "__main__":
asyncio.run(main())
Output is random given httpbin response. Should add to 5.
4 1

Run slow background blocking task from asyncio loop

I have asyncio crawler, that visits URLs and collects new URLs from HTML responses. I was inspired that great tool: https://github.com/aio-libs/aiohttp/blob/master/examples/legacy/crawl.py
Here is a very simplified piece of workflow, how it works:
import asyncio
import aiohttp
class Requester:
def __init__(self):
self.sem = asyncio.BoundedSemaphore(1)
async def fetch(self, url, client):
async with client.get(url) as response:
data = (await response.read()).decode('utf-8', 'replace')
print("URL:", url, " have code:", response.status)
return response, data
async def run(self, urls):
async with aiohttp.ClientSession() as client:
for url in urls:
await self.sem.acquire()
task = asyncio.create_task(self.fetch(url, client))
task.add_done_callback(lambda t: self.sem.release())
def http_crawl(self, _urls_list):
loop = asyncio.get_event_loop()
crawl_loop = asyncio.ensure_future(self.run(_urls_list))
loop.run_until_complete(crawl_loop)
r = Requester()
_url_list = ['https://www.google.com','https://images.google.com','https://maps.google.com','https://mail.google.com','https://news.google.com','https://video.google.com','https://books.google.com']
r.http_crawl(_url_list)
What I need now is to add some very slow beautifulsoap based function. I need that function do not block main loop and work as background process. For instance, I will handle HTTP responses.
I read python docs about it and found that: https://docs.python.org/3/library/asyncio-eventloop.html#asyncio.loop.run_in_executor
I tried to add it to my code, but it does not work as should (I use cpu_bound only for demo):
import asyncio
import aiohttp
import concurrent.futures
def cpu_bound():
return sum(i * i for i in range(10 ** 7))
class Requester:
def __init__(self):
self.sem = asyncio.BoundedSemaphore(1)
async def fetch(self, url, client):
async with client.get(url) as response:
data = (await response.read()).decode('utf-8', 'replace')
print("URL:", url, " have code:", response.status)
####### Blocking operation #######
loop = asyncio.get_running_loop()
with concurrent.futures.ProcessPoolExecutor() as pool:
result = await loop.run_in_executor(pool, cpu_bound)
print('custom process pool', result)
#################################
return response, data
async def run(self, urls):
async with aiohttp.ClientSession() as client:
for url in urls:
await self.sem.acquire()
task = asyncio.create_task(self.fetch(url, client))
task.add_done_callback(lambda t: self.sem.release())
def http_crawl(self, _urls_list):
loop = asyncio.get_event_loop()
crawl_loop = asyncio.ensure_future(self.run(_urls_list))
loop.run_until_complete(crawl_loop)
r = Requester()
_url_list = ['https://www.google.com','https://images.google.com','https://maps.google.com','https://mail.google.com','https://news.google.com','https://video.google.com','https://books.google.com']
r.http_crawl(_url_list)
For now, it doesn't work as expected, it blocks HTTP requests every time:
URL: https://www.google.com have code: 200
custom process pool 333333283333335000000
URL: https://images.google.com have code: 200
custom process pool 333333283333335000000
URL: https://maps.google.com have code: 200
custom process pool 333333283333335000000
URL: https://mail.google.com have code: 200
custom process pool 333333283333335000000
URL: https://news.google.com have code: 200
custom process pool 333333283333335000000
URL: https://video.google.com have code: 200
custom process pool 333333283333335000000
How to correctly put the task in the background inside the main asyncio process?
Are there best practices on how to do that in a simple way, or I should use Redis for task planning?
I believe that since you are setting your BoundedSemaphore to 1 it is only allowing one instance of your task to run at a time.
You can use the ratelimiter package to limit the number of concurrent requests in a certain amount of time.
I would also upload code that works for me. It is two independent async queues, and one of them spawn high-CPU consumption process in a separate loop:
import asyncio
import functools
import aiohttp
import concurrent.futures
def cpu_bound(num):
return sum(i * i for i in range(10 ** num))
class Requester:
def __init__(self):
self.threads = 3
self.threads2 = 10
self.pool = concurrent.futures.ProcessPoolExecutor()
async def fetch(self, url):
try:
timeout = aiohttp.ClientTimeout(total=10)
async with self.client.get(url, allow_redirects=False, verify_ssl=False, timeout=timeout) as response:
data = (await response.read()).decode('utf-8', 'replace')
print("URL:", url, " have code:", response.status)
resp_list = {'url': str(response.real_url), 'data': str(data), 'headers': dict(response.headers)}
return resp_list
except Exception as err:
print(err)
return {}
async def heavy_worker(self, a):
while True:
resp_list = await a.get()
if resp_list.keys():
####### Blocking operation #######
try:
loop = asyncio.get_event_loop()
result = await loop.run_in_executor(self.pool, functools.partial(cpu_bound, num=5))
print('wappalazer', result)
except Exception as err:
print(err)
#################################
a.task_done()
else:
a.task_done()
async def fetch_worker(self, q, a):
while True:
url = await q.get()
resp_list = await self.fetch(url)
q.task_done()
await a.put(resp_list)
async def main(self, urls):
# Create an queues those we will use to store our "workload".
q = asyncio.Queue()
a = asyncio.Queue()
# Create workers tasks to process the queue concurrently.
workers_fetch = [asyncio.create_task(self.fetch_worker(q, a)) for _ in range(self.threads)]
workers_heavy = [asyncio.create_task(self.heavy_worker(a)) for _ in range(self.threads2)]
for url in urls:
await q.put(url)
# wait for all tasks to be processed
await q.join()
await a.join()
# Cancel our worker tasks.
for worker in workers_fetch:
worker.cancel()
await asyncio.gather(*workers_fetch , return_exceptions=True)
for worker in workers_heavy:
worker.cancel()
await asyncio.gather(*workers_heavy , return_exceptions=True)
async def run(self, _urls_list):
async with aiohttp.ClientSession() as self.client:
task_for_first_run = asyncio.create_task(self.main(_urls_list))
await asyncio.sleep(1)
await task_for_first_run
print("All tasks completed")
def http_crawl(self, _urls_list):
asyncio.run(self.run(_urls_list))
r = Requester()
_url_list = ['http://aaaaaaaaaaaaaaaa.aaaaaaaaaaaaaaaaaaa.aa', 'https://www.google.com','https://images.google.com','https://maps.google.com','https://mail.google.com',
'https://news.google.com','https://video.google.com','https://books.google.com', 'https://www.google.com',
'https://images.google.com','https://maps.google.com','https://mail.google.com','https://news.google.com',
'https://video.google.com','https://books.google.com', 'https://www.google.com','https://images.google.com',
'https://maps.google.com','https://mail.google.com','https://news.google.com','https://video.google.com',
'https://books.google.com', 'https://www.google.com','https://images.google.com','https://maps.google.com',
'https://mail.google.com','https://news.google.com','https://video.google.com','https://books.google.com',
'https://www.google.com','https://images.google.com','https://maps.google.com','https://mail.google.com',
'https://news.google.com','https://video.google.com','https://books.google.com']
r.http_crawl(_url_list)

aiohttp and asyncio how to get response from http request and websocket in concurrent way?

I try to receive data from two endpoints in same time. But if websocket stop to send messages I won't receive data from request from "https://www.blabla.com". What is the best way for solving this problem?
import asyncio
import aiohttp
URL = 'wss://www.some_web_socket.io'
async def get_some_data(session):
url = "https://www.blabla.com"
async with session.get(url) as response:
data = await response.text()
return data
async def ws_handler(url):
async with aiohttp.ClientSession() as session:
async with session.ws_connect(url) as ws:
msg = await ws.receive()
while True:
some_data_from_get_request = await get_some_data(session)
msg_from_websocket = await ws.receive()
if msg.type == aiohttp.WSMsgType.TEXT:
print(stream_data)
print(some_data_from_get_request)
def _main():
asyncio.run(ws_handler(URL))
if __name__ == "__main__":
_main()
This code serializes the return values of HTTP and websocket communication:
while True:
some_data_from_get_request = await get_some_data(session)
msg_from_websocket = await ws.receive()
To be able to detect either of the two coroutines returning, you can use asyncio.wait(..., return_when=asyncio.FIRST_COMPLETED):
http_fut = asyncio.ensure_future(get_some_data(session))
ws_fut = asyncio.ensure_future(ws.receive())
pending = {http_fut, ws_fut}
while pending:
_done, pending = await asyncio.wait(pending, return_when=asyncio.FIRST_COMPLETED)
if http_fut.done():
some_data_from_get_request = http_fut.result()
...
if ws_fut.done():
msg_from_websocket = ws_fut.result()
...

Fetching multiple urls with aiohttp in python

In a previous question, a user suggested the following approach for fetching multiple urls (API calls) with aiohttp:
import asyncio
import aiohttp
url_list = ['https://api.pushshift.io/reddit/search/comment/?q=Nestle&size=30&after=1530396000&before=1530436000', 'https://api.pushshift.io/reddit/search/comment/?q=Nestle&size=30&after=1530436000&before=1530476000']
async def fetch(session, url):
async with session.get(url) as response:
return await response.json()['data']
async def fetch_all(session, urls, loop):
results = await asyncio.gather(*[loop.create_task(fetch(session, url)) for url in urls], return_exceptions= True)
return results
if __name__=='__main__':
loop = asyncio.get_event_loop()
urls = url_list
with aiohttp.ClientSession(loop=loop) as session:
htmls = loop.run_until_complete(fetch_all(session, urls, loop))
print(htmls)
However, this results in only returning Attribute errors:
[AttributeError('__aexit__',), AttributeError('__aexit__',)]
(which I enabled, otherwhise it would just break). I really hope there is somebody here, who can help with this, it is still kind of hard to find resources for asyncio etc. The returned data is in json format. In the end I would like to put all json dicts in a list.
Working example:
import asyncio
import aiohttp
import ssl
url_list = ['https://api.pushshift.io/reddit/search/comment/?q=Nestle&size=30&after=1530396000&before=1530436000',
'https://api.pushshift.io/reddit/search/comment/?q=Nestle&size=30&after=1530436000&before=1530476000']
async def fetch(session, url):
async with session.get(url, ssl=ssl.SSLContext()) as response:
return await response.json()
async def fetch_all(urls, loop):
async with aiohttp.ClientSession(loop=loop) as session:
results = await asyncio.gather(*[fetch(session, url) for url in urls], return_exceptions=True)
return results
if __name__ == '__main__':
loop = asyncio.get_event_loop()
urls = url_list
htmls = loop.run_until_complete(fetch_all(urls, loop))
print(htmls)

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