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ExecutorConfigEnvExt

nros::env

Trait ExecutorConfigEnvExt 

Source 
pub trait ExecutorConfigEnvExt {
    // Required method
    fn from_env() -> ExecutorConfig<'static>;
}
Expand description

ExecutorConfig::from_env(), as an extension trait.

issue 0687 — this was an inherent method on ExecutorConfig, which is defined in nros-node; an inherent method cannot be moved to another crate and keep its spelling, and the spelling is what ~26 call sites (most of them user-facing native examples) are written against. A trait keeps ExecutorConfig::from_env() working wherever it is in scope — the prelude carries it, so a consumer that already writes use nros::prelude::* changes nothing at all.

Required Methods§

Source

fn from_env() -> ExecutorConfig<'static>

Create a configuration from environment variables.

Reads:

  • NROS_LOCATOR — Middleware locator. Unset ⇒ empty (issue 0330: the active RMW backend applies its own default; e.g. zenoh dials nros_rmw_zenoh::DEFAULT_LOCATOR). Legacy name ZENOH_LOCATOR is accepted with a deprecation warning.
  • ROS_DOMAIN_ID — ROS 2 domain ID (default: 0).
  • NROS_SESSION_MODE — "client" or "peer" (default: "client"). Legacy name ZENOH_MODE is accepted with a deprecation warning.
  • NROS_RMW — the backend selector, through rmw_selector. issue 0687: Executor::open used to read this itself; it now takes ExecutorConfig::rmw, so a config built here still selects the backend the user named.

String values are cached in a process-global OnceLock on the first call and reused for the process lifetime — repeated calls do NOT accrete memory, and the returned &'static str fields point into that cache. Presence and the domain id are read live, so a caller that changes the environment between calls sees the change.

Panics on a malformed or out-of-range $ROS_DOMAIN_ID, like resolve_hosted and the C / C++ entries. A boot identity that cannot be resolved is a configuration error; the alternative is a node silently running on domain 0, which is what issue #206 removed everywhere else.

Dyn Compatibility§

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors§