Struct ExecutorConfig 

pub struct ExecutorConfig<'a> {
    pub locator: &'a str,
    pub mode: SessionMode,
    pub domain_id: u32,
    pub node_name: &'a str,
    pub namespace: &'a str,
    pub epoch_us: Option<fn() -> u64>,
}

Configuration for opening an embedded executor session.

Provides a backend-agnostic builder for configuring the middleware connection. The active Cargo feature (rmw-zenoh, rmw-xrce, or rmw-cffi) determines which backend is used.

Example

use nros::prelude::*;

let config = ExecutorConfig::new("tcp/127.0.0.1:7447")
    .node_name("talker")
    .domain_id(0);
let mut executor: Executor = Executor::open(&config)?;

Fields

locator: &'a str

Middleware-specific connection string.

mode: SessionMode

Session mode (client or peer).

domain_id: u32

ROS 2 domain ID.

node_name: &'a str

Node name.

namespace: &'a str

Node namespace.

epoch_us: Option<fn() -> u64>

RFC-0052 / phase-296 W3b.2 — wall-clock µs since the UNIX epoch, for now - header.stamp age monitors. Distinct from the monotonic clock_us: header.stamp is ROS (wall) time. None = no epoch source on this target — a baked max_age_ms contract with no epoch source is a BAKE-time error (fail-loud, never a silently-dead monitor). On std targets the executor falls back to SystemTime::now() when unset.

Implementations

impl<'a> ExecutorConfig<'a>

pub const fn new(locator: &'a str) -> ExecutorConfig<'a>

Create a new configuration with the given locator.

Defaults: Client mode, domain 0, node name "node", empty namespace.

pub const fn default_const() -> ExecutorConfig<'a>

Phase 104.C.3.3.b — Default-style constructor with an empty locator. Most users want ExecutorConfig::from_env() to pick up ZENOH_LOCATOR / ROS_DOMAIN_ID; this is the rclcpp-NodeOptions{} shape for callers that set every field explicitly via the chaining setters.

impl<'a> ExecutorConfig<'a>

pub const fn domain_id(self, id: u32) -> ExecutorConfig<'a>

Set the ROS 2 domain ID.

pub const fn node_name(self, name: &'a str) -> ExecutorConfig<'a>

Set the node name.

pub const fn namespace(self, ns: &'a str) -> ExecutorConfig<'a>

Set the node namespace.

pub const fn mode(self, mode: SessionMode) -> ExecutorConfig<'a>

Set the session mode.

pub const fn epoch_us(self, epoch: fn() -> u64) -> ExecutorConfig<'a>

RFC-0052 W3b.2 — set the wall-clock (epoch µs) source.

impl ExecutorConfig<'static>

pub fn from_env() -> ExecutorConfig<'static>

Create a configuration from environment variables.

Reads:

• NROS_LOCATOR — Middleware locator (default: "tcp/127.0.0.1:7447"). Legacy name ZENOH_LOCATOR is accepted with a deprecation warning.
• ROS_DOMAIN_ID — ROS 2 domain ID (default: 0).
• NROS_SESSION_MODE — Session mode: "client" or "peer" (default: "client"). Legacy name ZENOH_MODE is accepted with a deprecation warning.

Env-var values are cached in a process-global OnceLock on the first call and reused for the process lifetime — repeated calls do NOT re-read the environment and do NOT accrete memory. The returned &'static str fields point into the cache.

impl<'a> ExecutorConfig<'a>

pub fn resolve(baked: BootConfig<'a>, hosted_env: bool) -> ExecutorConfig<'a>

Resolve boot config under precedence model A (RFC-0045).

Per-field precedence (evaluated independently): env (hosted_env && var set) > baked > compiled default.

hosted_env=true enables the env-override layer (std only). Embedded callers always pass false; the env layer compiles out on no_std regardless of the flag value.

When hosted_env=true the env layer is queried fresh from the process environment at call time; string storage for env-derived fields comes from the process-global [EnvCache] (same backing store as ExecutorConfig::from_env). Passing BootConfig::default() with hosted_env=true is therefore equivalent to calling from_env() directly.

Note on env coupling: The env-presence checks below (NROS_LOCATOR/ZENOH_LOCATOR/ROS_DOMAIN_ID) must stay in sync with the env vars that [env_cache()] reads. If a new locator or domain env var is added there, add the corresponding presence check here too.

pub fn try_resolve( baked: BootConfig<'a>, hosted_env: bool, ) -> Result<ExecutorConfig<'a>, BootConfigError>

RFC-0045 / issue #206 — fallible resolve. Same precedence model A as resolve; returns BootConfigError instead of panicking on malformed / out-of-range identity input, so the C / C++ FFI shims can surface a return code. Validation is uniform across languages:

• ROS_DOMAIN_ID set but non-numeric → DomainIdParse (the pre-#206 C++ header silently collapsed this to domain 0; this resolver silently ignored it — both were wrong).
• any resolved domain id > DOMAIN_ID_MAX → DomainIdRange (including a BAKED value — the DDS backend would only fail later).
• NROS_NODE_NAME joins the hosted env rung (model A parity).

Trait Implementations

impl Default for ExecutorConfig<'_>

fn default() -> ExecutorConfig<'_>

Returns the “default value” for a type.