backend/rate_limiting/__init__.py

"""Rate limiting module for Portfolio Intelligence Platform.

Provides comprehensive rate limiting capabilities:
- Thread-safe and async token bucket implementations
- Redis-backed distributed rate limiting with in-memory fallback
- Multi-tier rate limiting (anonymous, authenticated, premium)
- Gradio-specific middleware for easy integration

Example usage:
    from backend.rate_limiting import (
        TieredRateLimiter,
        GradioRateLimitMiddleware,
        UserTier
    )
    from backend.config import settings

    # Create tiered limiter
    limiter = TieredRateLimiter(
        tier_limits={
            UserTier.ANONYMOUS: (10, 0.1),  # 10 requests, refill at 0.1/sec
            UserTier.AUTHENTICATED: (50, 0.5),
            UserTier.PREMIUM: (200, 2.0),
        },
        redis_url=settings.redis_url
    )

    # Create middleware
    middleware = GradioRateLimitMiddleware(limiter)

    # In Gradio handler
    def analysis_handler(portfolio_text: str, request: gr.Request):
        middleware.enforce(request)  # Raises gr.Error if limit exceeded
        # ... rest of handler
"""

from backend.rate_limiting.limiter import (
    ThreadSafeTokenBucket,
    AsyncTokenBucket,
    HybridRateLimiter,
    TieredRateLimiter,
    GradioRateLimitMiddleware,
    UserTier,
    RateLimitInfo,
)
from backend.rate_limiting.fixed_window import (
    FixedWindowRateLimiter,
    TieredFixedWindowLimiter,
)

__all__ = [
    "ThreadSafeTokenBucket",
    "AsyncTokenBucket",
    "HybridRateLimiter",
    "TieredRateLimiter",
    "GradioRateLimitMiddleware",
    "UserTier",
    "RateLimitInfo",
    "FixedWindowRateLimiter",
    "TieredFixedWindowLimiter",
]