Return default value when max retries attempted about backoff HOT 5 CLOSED

With the except block, code is not retrying at all because when exception is being raise first time, it is being handled by except block. So, backoff library is not considering the fact that function is throwing any exception in the first place.

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The documentation states:

When a give up event occurs, the exception in question is reraised and so code calling an on_exception-decorated function may still need to do exception handling.

So you should be able to do:

@backoff.on_exception(backoff.expo,
                      requests.exceptions.RequestException,
                      on_backoff=backoff_hdlr)
def get_url(url):
    return requests.get(url)

def get_url_or_default(url, default=None):
    try:
        return get_url(url)
    except requests.exceptions.RequestException:
        return default

Note: Code is an untested draft.

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@PatDue is correct. With on_exception, once the retrying is done, the exception that caused retry is raised and you can handle that exception and do whatever you like.

@sagarr I should note though, that in your code snippet you don't specify any of the keyword args that would cause backoff to give up at all. You need to use max_tries or max_time or giveup to trigger backoff.on_exception to stop trying.

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@mayank-kgp I don't know what you mean. Can you provide example code if you're reporting a bug?

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Hi,

I might be missing something here, I tried looking into docs and all issues, but didn't get anything..

Here what I want, I want to return default value once all the retrying is done, like

def backoff_hdlr(details):
   return None # tried getting value from URL, now just return None

@backoff.on_exception(backoff.expo,
                      requests.exceptions.RequestException,
                      on_backoff=backoff_hdlr)
def get_url(url):
    return requests.get(url)

Hi, I am facing the same problem as well. Were you able to solve this issue?
Is there a way for backoff decorator to return the value of backoff_hdlr as value of get_url function?

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