Auth (lexigram-auth)

Authentication and authorization for the Lexigram Framework — JWT, OAuth2, SAML, RBAC, and multi-tenancy.

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Overview

Complete authentication and authorization stack for Lexigram — JWT, OAuth2, RBAC, SAML, passkeys, and MFA. Provides a production-ready auth layer with multiple authentication strategies, policy-based access control, session management, and seamless integration with lexigram-web middleware.

Use AuthModule.configure() to register the auth bundle and protect routes with @require_auth, @require_roles, and @require_permissions decorators.

Full documentation: docs.lexigram.dev

Install

uv add lexigram-auth
# Optional extras
uv add "lexigram-auth[oauth2,saml]"

Quick Start

from lexigram import Application
from lexigram.di.module import Module, module
from lexigram.auth import AuthModule, AuthConfig, JWTConfig

@module(imports=[
    AuthModule.configure(
        config=AuthConfig(
            secret_key="your-secret-key",
            token=JWTConfig(secret_key="your-jwt-secret"),
        )
    )
])
class AppModule(Module):
    pass


async def main() -> None:
    async with Application.boot(modules=[AppModule]) as app:
        # app is running — resolve services from app.container
        ...


if __name__ == "__main__":
    import asyncio

    asyncio.run(main())

Configuration

Note: AuthConfig requires both secret_key and token.secret_key — pass an explicit config via AuthModule.configure().

Option 1 — YAML file

application.yaml

auth:
  secret_key: "your-secret-key"
  token:
    secret_key: "your-jwt-secret"
    algorithm: "HS256"
    access_token_expire: "30m"
  rbac:
    enabled: true
    default_role: "viewer"

Option 2 — Profiles + Environment Variables (recommended)

export LEX_AUTH__SECRET_KEY=your-secret-key
export LEX_AUTH__TOKEN__SECRET_KEY=your-jwt-secret
export LEX_AUTH__TOKEN__ALGORITHM=HS256
export LEX_AUTH__RBAC__DEFAULT_ROLE=viewer

Option 3 — Python

from lexigram.auth import AuthModule, AuthConfig, JWTConfig
from lexigram.contracts.core import Duration

config = AuthConfig(
    secret_key="your-secret-key",
    token=JWTConfig(
        secret_key="your-jwt-secret",
        algorithm="HS256",
        access_token_expire=Duration.minutes(30),
    ),
)
AuthModule.configure(config)

Config reference

Field	Default	Env var	Description
secret_key	—	LEX_AUTH__SECRET_KEY	Top-level signing secret (required)
token.secret_key	—	LEX_AUTH__TOKEN__SECRET_KEY	JWT signing secret (required)
token.algorithm	HS256	LEX_AUTH__TOKEN__ALGORITHM	JWT algorithm: HS256, RS256, ES256
token.access_token_expire	30m	LEX_AUTH__TOKEN__ACCESS_TOKEN_EXPIRE	Access token lifetime (duration string, e.g. 30m, 1h30m)
rbac.enabled	True	LEX_AUTH__RBAC__ENABLED	Enable RBAC
rbac.default_role	viewer	LEX_AUTH__RBAC__DEFAULT_ROLE	Default role for new users

Module Factory Methods

Method	Description
AuthModule.configure(...)	Configure with explicit AuthConfig
AuthModule.stub()	Minimal config for testing

Key Features

• JWT authentication — HS256/RS256, key rotation, token blacklisting
• OAuth2 / OIDC — authlib-backed: Google, GitHub, custom providers
• SAML 2.0 — Enterprise SSO via pysaml2
• Passkeys (WebAuthn) — FIDO2 device-based authentication
• MFA (TOTP) — Time-based one-time passwords
• RBAC — Role/permission inheritance with policy expressions
• Session management — Device-aware sessions with concurrency limits
• Token binding — IP address binding to prevent token theft

Testing

async with Application.boot(modules=[AuthModule.stub()]) as app:
    # your test code
    ...

Key Source Files

File	What it contains
src/lexigram/auth/module.py	AuthModule definition
src/lexigram/auth/config.py	AuthConfig, JWTConfig (+ allow_unverified_dev), RBACConfig
src/lexigram/auth/di/bundle_provider.py	AuthBundleProvider wiring
src/lexigram/auth/di/sub_providers/token_provider.py	TokenProvider (boots policy)
src/lexigram/auth/authn/jwt.py	JWTTokenManager implementation
src/lexigram/auth/authn/_jwt_lifecycle.py	verify_token (enforces policy)
src/lexigram/auth/authz/service.py	AuthorizationService

JWT verification policy

lexigram-auth enforces verified-only JWT decoding by default.

Environment	Secret present	allow_unverified_dev	Behaviour
PRODUCTION / STAGING	yes	any	Verified-only. Boot succeeds.
PRODUCTION / STAGING	no	any	Raises ConfigurationError at boot. Flag ignored.
DEVELOPMENT	yes	any	Verified-only. Boot succeeds.
DEVELOPMENT	no	False (default)	Raises ConfigurationError at boot.
DEVELOPMENT	no	True	Boots. Single warning logged. Tokens decoded without signature verification.

Enable the dev opt-in

Via environment variable:

export LEX_AUTH__TOKEN__ALLOW_UNVERIFIED_DEV=true

Via Python config:

from lexigram.auth.config import AuthConfig, JWTConfig

config = AuthConfig(
    secret_key="any-placeholder",
    token=JWTConfig(
        secret_key="any-placeholder",
        allow_unverified_dev=True,
    ),
)

The allow_unverified_dev flag is silently ignored in PRODUCTION and STAGING; the service always rejects the flag in those environments and raises if no real secret is configured. This prevents the Piccolina-style mistake of silently trusting unverified tokens in production when a secret env-var is missing.