marque-config

Layered configuration loading for Marque.

marque-config resolves a single, validated Config from up to four sources and hard-fails fast on misuse. The engine never reads files itself — it takes the resolved Config as a constructor argument.

Role in Marque

.marque.toml ─┐
.marque.local.toml ─┼─→ marque-config ─→ Config ─→ marque-engine
env vars ─┘            (validates, merges)
CLI flags ─────────────┘ (caller-applied)

Precedence

Highest wins:

CLI flags  >  env vars  >  .marque.local.toml  >  .marque.toml

load(start_dir) walks upward from start_dir and stops at the first .marque.toml, .git/, or filesystem root. load_with_explicit_config(path) short-circuits the walk and uses path directly.

Usage

use marque_config::load;

let cwd = std::env::current_dir()?;
let config = load(&cwd)?;

println!("threshold = {}", config.confidence_threshold());
# Ok::<(), Box<dyn std::error::Error>>(())

Config files

.marque.toml — committed, project/org policy:

[capco]
version = "ISM-v2022-DEC"

[rules]
E001 = "fix"                    # portion-mark-in-banner; off | info | warn | error | fix
E002 = "warn"                   # missing-usa-trigraph
"missing-usa-trigraph" = "warn" # equivalent — rule names are accepted as aliases

[corrections]
"SERCET" = "SECRET"

.marque.local.toml — gitignored, per-user identity. Never commit:

[user]
classifier_id = "TEST-12345"
classification_authority = "EO 13526"
default_reason = "1.4(c)"              # optional
derived_from_default = "Multiple Sources"  # optional

Rule keys: IDs or names

The [rules] section accepts either the canonical rule ID (E001) or the rule name (portion-mark-in-banner) as the key. Both forms resolve to the same rule at engine construction time. Using the name form makes configs more self-documenting; the ID form is shorter and stable across renames.

Writing both forms with different severities for the same rule is rejected at engine construction time — one form would have silently won the HashMap iteration race and the other would have been dropped. Writing both forms with the same severity is accepted silently.

Hard-fail validators

The loader (or engine constructor) refuses to produce a Config / Engine (exit code in parens) when:

• .marque.toml contains a [user] section — identity must live only in .marque.local.toml or env vars (FR-010, exit 65).
• [capco] version does not match the compiled marque_ism::SCHEMA_VERSION (FR-011, exit 65).
• confidence_threshold is outside [0.0, 1.0] (exit 65).
• A rule severity string is not one of off, info, warn, error, fix (exit 65).
• The config file cannot be read (exit 74).
• A [rules] key is not a registered rule ID or name — the engine emits EngineConstructionError::UnknownRuleOverride with a best-effort "did you mean…" suggestion (exit 65).
• A [rules] section specifies the same rule two different ways with conflicting severities — the engine emits EngineConstructionError::ConflictingRuleOverride (exit 65).

ConfigError::exit_code() and EngineConstructionError::exit_code() return the appropriate code for the CLI.

Public types

License

Marque License 1.0 (LicenseRef-MarqueLicense-1.0). See LICENSE.md.