Examples

The repository ships two runnable applications under examples/. Both use the real adapter surface (with_guard applied to axum routers with Router::layer).

The example crates are workspace members and build against the in-repository path dependencies, so building them locally requires sibling tower-guard-rs and guard-core-rs checkouts (see the repository README).

simple_app

A minimal guarded axum application (examples/simple_app):

Route	Guard	Behavior
GET /health	excluded	200 ok
GET /	guarded	200 greeting
GET /search?q=...	guarded	200 search ok, or 400 when the query trips the engine
POST /echo	guarded	echoes the body; 400 for a threat, 413 over the body cap

The excluded path is expressed with axum composition: the guarded routes live on a router carrying the guard layer, and Router::merge combines it with an unguarded /health router.

Run it:

cargo run -p axum-guard-simple-app

advanced_app

A production-shaped guarded application (examples/advanced_app) that demonstrates the two knobs a real deployment tunes: environment-driven engine configuration and route-scoped guard configuration. The /admin sub-router is screened by a second, stricter GuardLayer (threat-score threshold halved by default), while general routes use the default-derived configuration, and GET /health lives on the unguarded router (nest plus merge keep the two guard trees and the health route apart).

Configuration

Variable	Meaning	Default
APP_ADDR	Listen address	0.0.0.0:8080
GUARD_MAX_CONTENT_LENGTH	Engine max_content_length	10000
GUARD_MAX_FULL_SCAN_BYTES	Engine max_full_scan_bytes (also the default body cap)	262144
GUARD_PRESERVE_ATTACK_PATTERNS	Engine preserve_attack_patterns	true
GUARD_SEMANTIC_THRESHOLD	Engine semantic_threshold	0.7
GUARD_THREAT_SCORE_THRESHOLD	Engine threat_score_threshold (general routes)	1.0
GUARD_BODY_CAP	Adapter body buffering cap	GUARD_MAX_FULL_SCAN_BYTES
GUARD_ADMIN_THREAT_SCORE_THRESHOLD	Threat-score threshold for the /admin guard tree	half the general threshold

Routes

Route	Guard tree	Behavior
GET /health	excluded	200 ok
GET /	general	200, greeting text
GET /search?q=...	general	200, or 400 on a threat
POST /echo	general	echoes the body; 400/413 from the guard
GET /admin/stats	stricter admin guard	screened by a second GuardLayer with a lower threat-score threshold

Run it directly or with the provided Docker setup:

cargo run -p axum-guard-advanced-app

cd examples/advanced_app
docker compose up