{"id":6181,"date":"2020-07-02T15:13:54","date_gmt":"2020-07-02T13:13:54","guid":{"rendered":"https:\/\/www.codemotion.com\/magazine\/?p=6181"},"modified":"2023-06-19T12:33:13","modified_gmt":"2023-06-19T10:33:13","slug":"logging-in-python-a-broad-gentle-introduction","status":"publish","type":"post","link":"https:\/\/www.codemotion.com\/magazine\/ai-ml\/big-data\/logging-in-python-a-broad-gentle-introduction\/","title":{"rendered":"Logging in Python: a broad, gentle introduction"},"content":{"rendered":"\t\t\t\t
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\n\t\t\t\t\t\t\tTable Of Contents\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t
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  1. Why Logging<\/a>
  2. Logging module: intro and main actors<\/a>
  3. Logger class methods<\/a>
  4. Handler class method<\/a>
  5. Formatter class methods<\/a>
  6. From theory and dummy examples to the real word<\/a>
  7. Conclusion<\/a><\/ol>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\n\n\n

    Not all data scientists<\/a> have a computer science<\/span> background – I received my bachelor\u2019s degree in Statistics<\/span>, for example. As I moved into data<\/span>, I noticed that I was good at scripting<\/span>, but was not able to create a \u2018production-quality\u2019 code. A fundamental step in writing production-quality code is the ability to log properly. In this article, I will explain how to log in Python<\/span>.<\/p>\n\n\n\n

    First, we will explore why logging is a fundamental part of any real-world application<\/span>. Next, we will look at the main actors in Python<\/span>\u2019s logging module. Each actor is introduced in both a theoretical and a practical way. We will become familiar with each of these actors by writing simple code examples.<\/p>\n\n\n\n

    At the end of the article, an example of how to embed the logging library in a structured data<\/span> science project is shown. All the examples used in the article are available in my GitHub repo<\/a>. You can clone this and play with the examples.<\/p>\n\n\n\n

    Why Logging<\/h2>\n\n\n\n

    Logging<\/span> is the key to enabling <\/em><\/strong>diagnostic auditing<\/strong>. With a proper log file<\/span>, it\u2019s possible to know what has happened in the application<\/span>. Has the application<\/span> run smoothly? Has a weird error<\/span> occurred? Does the model perform as expected?<\/p>\n\n\n\n

    Let\u2019s make these questions more practical by defining an example that we will carry through this article.<\/p>\n\n\n\n

    We have just developed an application<\/span> that makes weather forecasts.<\/p>\n\n\n\n

    Our application<\/span> works as follows:<\/p>\n\n\n\n