vessel/README.md

Vessel

vessel::Vessel is a simple, immutable value bag for Rust – inspired by Go's context.Context, but focused solely on storing and propagating context in a simple manner.

✨ Features

• Immutable: setting a value returns a new Vessel.
• Ordered: uses a BTreeMap internally for deterministic iteration.
• Ergonomic: fluent API with zero dependencies (aside from the standard library).
• Useful for threading context-like metadata (e.g., request IDs, tenant info) through application layers.

📦 Example

use vessel::Vessel;

let vessel = Vessel::new();
let vessel = vessel.with_value("request_id", "abc-123");

assert_eq!(vessel.get_value("request_id"), Some(&"abc-123".to_string()));

📚 API

pub fn new() -> Self;
pub fn with_value(&self, key: &str, value: &str) -> Self;
pub fn get_value(&self, key: &str) -> Option<&String>;
pub fn get_values(&self) -> &BTreeMap<String, String>;

• with_value: Adds a key-value pair to the vessel, returning a new instance.
• get_value: Retrieves a value for a given key.
• get_values: Returns all key-value pairs.

🧪 Tests

Run tests with:

cargo test

📜 License

MIT