Savant Dev Mode: Reload Parameters Without Restarting Pipeline

Hey guys! Ever been in that situation where you're deep in development mode, tweaking parameters in your config files, and dreading the thought of restarting the entire pipeline just to see your changes take effect? Well, you're not alone! This article addresses a common challenge faced by Savant users: how to reload parameters from a configuration file without interrupting the pipeline's execution during development. Let's dive in and explore the solutions.

The Challenge: Parameter Updates in Dev Mode

In the world of Savant, the development mode is a lifesaver. It allows you to modify your code and see the changes reflected almost instantly, without the need for a full pipeline restart. This drastically speeds up the development process. However, the convenience hits a snag when your components rely on parameters stored in external configuration files, like config.yml. Imagine you're fine-tuning a critical threshold or adjusting a scaling factor. Each time you tweak the yml file, a pipeline restart feels like an eternity, breaking the smooth flow of development.

The core issue stems from how most applications, including Savant-based systems, typically load their configuration parameters. At startup, the application reads the config.yml file and stores these values in memory. Subsequent changes to the file aren't automatically reflected in the running application. This is a common design pattern, as constantly monitoring and reloading configuration files could introduce performance overhead and potential instability in a production environment. However, in development, this behavior becomes a bottleneck, hindering rapid iteration and experimentation. We need a way to signal the running components to refresh their parameters without bringing the entire system down.

One approach could be to implement a file-watching mechanism. This would involve a component that actively monitors the config.yml file for changes. Upon detecting a modification, it would trigger a reload of the parameters. However, this introduces complexity, as you need to ensure thread safety and handle potential race conditions. Moreover, different components might require different strategies for reloading their parameters. Some might be able to update their internal state on the fly, while others might need to be partially reinitialized. Therefore, a more elegant and centralized solution is often preferred. Another strategy might involve using a dedicated configuration management tool. These tools often provide mechanisms for dynamically updating application configurations without requiring restarts. However, integrating such a tool into a Savant pipeline might add significant overhead and complexity, especially for smaller projects. So, what's the sweet spot? Let's explore some practical solutions that balance simplicity and effectiveness.

Solutions for Parameter Reloading

Fortunately, there are several strategies to tackle this challenge, ranging from simple workarounds to more sophisticated solutions. Let's explore a few options, weighing their pros and cons for different scenarios.

1. Manual Reload via API or Signal

The simplest approach is often the most effective for development. This involves exposing an API endpoint or a signal that your components can listen to, triggering a parameter reload when activated. Think of it as a manual