Articles

Restarting uvicorn Workers with the SIGHUP Signal

Learn about process management in Python's uvicorn web server and how to use signals to restart workers and to increment/decrement the number of workers.

By Christoph Schiessl on Python

Using the If-Match Header to Avoid Collisions

Prevent lost updates in HTTP APIs using ETag and If-Match headers to block conflicting updates and ensure data integrity.

By Christoph Schiessl on Python and FastAPI

Showcasing Weak and Strong ETag Headers with FastAPI

Comparison of strong and weak ETag headers in HTTP caching, with an example using FastAPI to demonstrate their behavior.

By Christoph Schiessl on Python and FastAPI

The Built-In sorted() Function

Python's sorted() function makes sorting easy and performant, guaranteeing stability and allowing descending order and custom mapping.

By Christoph Schiessl on Python

Starting and Stopping uvicorn in the Background

Learn how to start and stop uvicorn in the background using a randomly selected free port number. Useful for running test suites that require live-webservers.

By Christoph Schiessl on Python

The Built-in chr() and ord() Functions

Discover Python's built-in functions chr() and ord() for handling Unicode characters and converting between integers and characters.

By Christoph Schiessl on Python

Disabling 304 Not Modified in FastAPI's StaticFiles

Dealing with caching issues in FastAPI's StaticFiles sub-application and a monkey patching workaround to disable caching.

By Christoph Schiessl on Python and FastAPI

The Built-in bin(), oct() and hex() Functions

Learn about the Python built-in functions bin(), oct(), and hex() functions for converting integers to binary, octal, and hexadecimal representations.

By Christoph Schiessl on Python

Function Overloading with the @overload Decorator

Python doesn't support true function overloading, but can fake it using the typing module's @overload decorator.

By Christoph Schiessl on Python

How To Validate Word Counts for SEO

Learn how to validate the word count of your pages for SEO purposes. It uses JavaScript to parse your sitemap.xml and count the words on all mentioned pages.

By Christoph Schiessl on JavaScript

The Built-in min() and max() Functions

Python's min() and max() functions can take an iterable or multiple positional parameters, and support a key parameter for custom comparisons.

By Christoph Schiessl on Python

How to Avoid Conflicts and Let Your OS Select a Random Port

Learn how to have your OS randomly select a port number for your web server to get around the issue of hard-coded ports during development.

By Christoph Schiessl on Python, FastAPI, and DevOps

The Built-in sum() Function

In this article, we explore Python's built-in sum() function, its parameters, and some extreme use cases it wasn't even designed for.

By Christoph Schiessl on Python

HTTP Caching with Last-Modified and If-Modified-Since Headers

Learn about timestamp-based caching in HTTP using the Last-Modified and If-Modified-Since headers, with Python's FastAPI as an example.

By Christoph Schiessl on Python and FastAPI

How to Validate your Page Titles and Descriptions for SEO

Learn how to use JavaScript to programmatically check the meta information of all pages listed in your sitemap.xml to potentially rank better on Google.

By Christoph Schiessl on JavaScript

Extracting all URLs of your sitemap.xml with JavaScript

Learn JavaScript techniques needed to parse your sitemap.xml in order to obtain a list of all pages making up your website.

By Christoph Schiessl on JavaScript

Date/Time Formatting According to RFC 5322

Learn about the custom date/time formatting rules defined in legacy standards like RFC 5322 and how to work with them using Python's datetime module.

By Christoph Schiessl on Python

How to Format all JSON Files in a Git Repository

Do you struggle with inconsistent JSON formatting across your Git repository? Learn how to reformat everything using Python with this step-by-step guide.

By Christoph Schiessl on DevOps, Git, and Python

HTTP Caching with ETag and If-None-Match Headers

Learn how to use ETag and If-None-Match headers to limit your web application's resource consumption by preventing data retransfers.

By Christoph Schiessl on Python and FastAPI

Word Level Levenshtein Distance

This article explains how to use the Levenshtein algorithm to compare sentences by looking for word differences instead of character differences.

By Christoph Schiessl on Python

Encapsulation: Public, Protected, and Private Members

Learn about encapsulation in Python. This article explains public, protected, and private members and the conventions used to implement them.

By Christoph Schiessl on Python

Function Definition with Catch-All Parameters

Learn how to use catch-all parameters in Python functions with this guide. Capture excess positional and keyword arguments to make your functions more flexible.

By Christoph Schiessl on Python

Why JavaScript’s undefined Isn’t What You Think It Is

In this informative article, you learn that undefined is not a keyword in JavaScript, and it's up to you to ensure it refers to the value its name suggests.

By Christoph Schiessl on JavaScript

Repairing Corrupted Indexes with REINDEXing

This article outlines how to rebuild indexes with REINDEX. As an example, we will deliberately corrupt an index for a column that uses a custom ENUM column.

By Christoph Schiessl on PostgreSQL

Generating Random Numbers According to a Probability Distribution

Learn how to generate random numbers in PostgreSQL whose distribution follows the uniform, exponential, or normal probability distribution.

By Christoph Schiessl on PostgreSQL

Custom ENUM Type Columns and ORDER BY

Learn how custom ENUM types in PostgreSQL can affect SELECT queries and ORDER BY clauses. Be mindful of indexing and typecasting.

By Christoph Schiessl on PostgreSQL

Force Index Usage by Manipulating the Query Planner

Learn how to manipulate PostgreSQL's query planner to force it to use your indexes while working on optimizing the performance of your queries.

By Christoph Schiessl on PostgreSQL

Telling Docker Who You Are

Learn how to avoid permission issues when creating files on a Docker bind-mount volume from within a container and manage user IDs and group IDs on Linux.

By Christoph Schiessl on DevOps and Docker

Boolean Operators and Short-Circuiting

Fully understand Python's boolean operators for negation, conjunction, and disjunction. Master operator precedence and short-circuiting.

By Christoph Schiessl on Python

The Built-in any() Function

Learn how to use the built-in any() function in Python to determine if any element in an iterable is True, with implementation and performance insights.

By Christoph Schiessl on Python

The Built-in id() Function

Learn about object identities and comparisons in Python. Discover the built-in id() function, the is and is not operators, and more.

By Christoph Schiessl on Python

How to Find the First/Last Day of a Month from a given Date

Learn how to calculate a month's first and last days using Python's built-in datetime module, with step-by-step explanations and code examples.

By Christoph Schiessl on Python

The Built-in bool() Class

Learn about boolean values in Python and the standard truth testing procedure. Understand how objects are converted to True or False.

By Christoph Schiessl on Python

How to Find the First/Last Day of a Year from a given Date

Learn how to find the first and last day of a year with Python's datetime module. This article explains step by step what you need to know.

By Christoph Schiessl on Python

Serving Websites with FastAPI's StaticFiles

Learn how to serve a static site using FastAPI. Perfect for locally testing statically generated websites, for instance, with httpie.

By Christoph Schiessl on Python and FastAPI

Comparing Strings using Levenshtein Distance

Learn about the Levenshtein distance algorithm, a popular and easy-to-implement way to measure the similarity between two strings.

By Christoph Schiessl on Python

Function Definition with Keyword-Only Parameters

Learn about keyword-only parameters in Python, how to define them, and their interplay with position-only parameters.

By Christoph Schiessl on Python

Function Definition with Position-Only Parameters

Learn about positional parameters in Python and a special syntax that allows functions to declare certain parameters as position-only.

By Christoph Schiessl on Python

Function Definition with Default Parameters

Learn about Python functions with default parameters. Understand how default parameters work and some essential restrictions and evaluation rules.

By Christoph Schiessl on Python

The Built-in callable() Function

Learn about the callable() function in Python. This article explains how everything in Python is potentially callable, including classes and instances.

By Christoph Schiessl on Python

Function Definition with Simple Parameters

Learn about functions with simple parameters in Python, including how the called can decide to use positional or keyword notation.

By Christoph Schiessl on Python

Function Definition Basics

Explore Python's function definition statement and discover its features with this series of articles. Get started with this simple introduction.

By Christoph Schiessl on Python

Portability via Static Linking of libpq

Learn how to remove LDAP support from PostgreSQL packages to remove indirect dependencies, thereby making your programs more portable across systems.

By Christoph Schiessl on DevOps, PostgreSQL, and Docker

The Built-in all() Function

Learn how to use the built-in all() function in Python for boolean logic, with examples and different implementations.

By Christoph Schiessl on Python

Caching Expensive Queries with MATERIALIZED VIEWs

Learn how to use PostgreSQL's MATERIALIZED VIEWs to improve performance of complex queries. Persist query results and refresh them manually or automatically.

By Christoph Schiessl on PostgreSQL

Orphaned Branches in Git

Learn about Git's internal data structure and how orphaned branches can be used to create separate histories with their own root commits.

By Christoph Schiessl on DevOps and Git

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