Make your functions more tenace in Python

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There are many situations where we want to retry specific operations in case of errors. This is often the case in distributed systems (calling an external API, saving data in a remote data store, etc…). Here, I will present a nice Python library to do that.

Installation

The library is called tenacity. To install it, you will need Python 3.7 or higher.

$ pip install tenacity
# or with poetry
$ poetry add tenacity

If you don’t know poetry, I have a nice introduction to it here:

What is new in poetry 1.2

Usage

The simplest usage is to use the retry decorator it provides without parameters.

from tenacity import retry


@retry
def retry_without_limit():
    print('retrying forever and ever!')
    raise Exception


if __name__ == '__main__':
    retry_without_limit()

Notes:

• If you run the previous code, it will run indefinitely since there is no stop condition. 😜
• In the next examples, I will omit the if…