Crate dynamic_config_actix 

A request-scoped configuration snapshot for Actix Web.

use actix_web::{get, App, HttpServer};
use dynamic_config_actix::{Config, DynamicConfig};
use dynamic_config_web_core::sections;

#[get("/")]
async fn index(server: Config<Server>, features: Config<Features>) -> String {
    // Both came out of one snapshot, taken when the request began.
    // `Sections::take` retries if a reload lands mid-read, so these
    // two cannot be different generations.
    format!("{} {}", server.port, features.cache)
}

HttpServer::new(|| {
    App::new()
        .wrap(DynamicConfig::new(sections![Server, Features]))
        .service(index)
});

What this is for

Actix runs handlers across several worker threads, and Server::current() is an atomic load that every worker can make without a lock. That part is already right. What it does not give you is two sections that agree: a reload landing between two reads lets one response mix generations.

DynamicConfig reads every listed section once, before the handler runs, and puts the result in the request’s extensions. Config<T> reads it back out.

Note what is not here: no web::Data<ServerConfig>. Handing a snapshot to the app factory freezes it at start-up, and each worker then serves the configuration that existed when it was built.

What this is not

It does not load configuration, watch files, or own a WatchHandle. That stays in the startup code that calls init() and holds the handles for the life of the process.

Macros

sections

The sections a request reads, by type.

Structs

Config

One section of this request’s configuration.

ConfigSections

The sections a request reads, and how to read each one.

DynamicConfig

Takes one snapshot per request and puts it in the request’s extensions.

SnapshotMiddleware

The service DynamicConfig wraps an application in.

Enums

OutOfScope

Why a section is not in this request’s snapshot.

SnapshotMissing

Why a Config extractor could not answer.

Functions

snapshot

The snapshot this request began with, for code holding an HttpRequest rather than using the extractor.