Learning

💡 The problem Welcome back, it’s been quite a long time since my last ramblings on the D Programming Language! This post is born from a necessity. An old project of mine, the D Koans, was using an external library to simplify unit testing, which is more or less the core of the whole project. Unfortunately, the library started giving some deprecation warnings when compiled with recent D versions. Since the D Language already has an internal unit testing framework, I thought it would be nice to remove the single dependency and rely only on the standard library. Initially, with some global search/replace, I managed to convert all the tests to unittest blocks. ...

💭 What ? Imagine a web server that only starts when someone actually tries to access it. Or a database that spins up only when a query comes in: this is the magic of socket activation. The concept is not new, as old-school sysadmins may are used to see something like inetd or xinetd for on-demand service activation in the past. As some cool projects like cockpit have already started using this little-known feature, in this blog post we’ll see the basics and try to get familiarity with the tooling. ...

In this post we are going to write a new module for python: a very simple function exported from Rust that we can consume in the Python interpreter. We’ll leverage the PyO3 Rust bindings for the Python interpreter. Let’s start with a new Cargo project: $ cargo init --lib demo_rust_lib and insert the required settings in Cargo.toml: [package] name = "rusty" version = "0.1.0" edition = "2021" [lib] name="rusty" crate-type = ["cdylib"] [dependencies.pyo3] version = "*" [features] extension-module = ["pyo3/extension-module"] default = ["extension-module"] now it’s a matter to write our library; luckily the PyO3 library exposes a lot of useful types for python interop; the only thing we need to add is an extra fn named as our module that “exports” the functions we want to make available in the Python layer: ...

Let’s get our feet wet; in this first part I’ll write about a very simple way to interface Rust and Python. First of all let’s build a Rust dynamic library with some basic functions. // this file is: src/lib.rs #[no_mangle] pub extern "C" fn hello() { println!("Hello from the library!"); } #[no_mangle] pub extern "C" fn sum(a: i32, b: i32) -> i32 { a + b } your Cargo.toml should look like this: [package] name = "pyrust" version = "0.1.0" edition = "2018" [dependencies] [lib] crate-type = ["cdylib"] compile the library with cargo build ...