Unable to handle ratelimited

[rcsrao]

while True:
  try:
    response = send_slack_message(channel, message)
  except SlackApiError as e:
    if e.response["error"] == "ratelimited":
      # The `Retry-After` header will tell you how long to wait before retrying
      delay = int(e.response.headers['Retry-After'])
      print(f"Rate limited. Retrying in {delay} seconds")
      time.sleep(delay)
      response = send_slack_message(channel, message)
    else:
      # other errors
      raise e

This is helpless it seems,

**During handling of the above exception, another exception occurred:**

Traceback (most recent call last):
  File "/usr/local/Cellar/python@3.8/3.8.5/Frameworks/Python.framework/Versions/3.8/lib/python3.8/threading.py", line 932, in _bootstrap_inner
    self.run()
  File "/usr/local/Cellar/python@3.8/3.8.5/Frameworks/Python.framework/Versions/3.8/lib/python3.8/threading.py", line 870, in run
    self._target(*self._args, **self._kwargs)
  File "dpxbot.py", line 146, in process_message
    self.hello(message) 
  File "dpxbot.py", line 189, in hello
    response = self.send_slack_message(message, slack_ts, user_id, channel_id)
  File "dpxbot.py", line 212, in send_slack_message
    rep = self.web_client.chat_postMessage(
  File "/usr/local/lib/python3.8/site-packages/slack/web/client.py", line 1041, in chat_postMessage
    return self.api_call("chat.postMessage", json=kwargs)
  File "/usr/local/lib/python3.8/site-packages/slack/web/base_client.py", line 150, in api_call
    return self._sync_send(api_url=api_url, req_args=req_args)
  File "/usr/local/lib/python3.8/site-packages/slack/web/base_client.py", line 241, in _sync_send
    return self._urllib_api_call(
  File "/usr/local/lib/python3.8/site-packages/slack/web/base_client.py", line 369, in _urllib_api_call
    return SlackResponse(
  File "/usr/local/lib/python3.8/site-packages/slack/web/slack_response.py", line 194, in validate
    raise e.SlackApiError(message=msg, response=self)
slack.errors.SlackApiError: The request to the Slack API failed.
The server responded with: {'ok': False, 'error': 'ratelimited'}

Any help would be appreciated.

[seratch]

According to the stacktrace, your code seems to be using threading. As ratelimited errors are raised per API endpoint per app per workspace, your app is unable to simultaneously call the same endpoint once after you’ve got the error. This means you app has to completely stop calling the API while waiting for the duration of retry-after. The example in the doc works only when you run it in a single thread.

[rcsrao]

@seratch Makes sense!

Any help in handling multithreading? We would like to test the clients with the maximum load (50 requests at a time for an instance) to design the scalable systems.

[seratch]

A common solution is to have a queue with a good consideration of rate limits. Java SDK’s async client has such a mechanism: https://slack.dev/java-slack-sdk/guides/web-api-basics#rate-limits

[rcsrao]

This block made us better to handle the issue,

attempt = 1
        for _ in range(0,2):
            while True:
                try:
                  print(f"Attempt: {attempt} --- " + str(message['payload']['event']['text']))
                  sleep(1)
                  response = self.send_slack_message(message, slack_ts, user_id, channel_id)
                  attempt += 1
                  break
                except SlackApiError as exception:
                    attempt += 1
                    # The `Retry-After` header will tell you how long to wait before retrying
                    wait_time = float(exception.response.headers["Retry-After"])
                    print(f"Rate limited. Retrying in {wait_time} seconds")
                    time.sleep(wait_time)
                    continue
            attempt = 1
            break

[seratch]

@rcsrao Would you mind closing this issue now? I think your question has been answered.

[seratch]

As I've already provided an answer here, please allow me to close this issue now. Feel free to write in or reopen as necessary.