Files
routstr-core/routstr/payment/helpers.py
T

318 lines
10 KiB
Python

import json
import math
from typing import Mapping
from fastapi import HTTPException, Response
from fastapi.requests import Request
from sqlmodel import select
from sqlmodel.ext.asyncio.session import AsyncSession
from ..core import get_logger
from ..core.db import ModelRow
from ..core.settings import settings
from ..wallet import deserialize_token_from_string
from .models import Pricing
logger = get_logger(__name__)
def check_token_balance(headers: dict, body: dict, max_cost_for_model: int) -> None:
if x_cashu := headers.get("x-cashu", None):
cashu_token = x_cashu
logger.debug(
"Using X-Cashu token",
extra={
"token_preview": cashu_token[:20] + "..."
if len(cashu_token) > 20
else cashu_token
},
)
elif auth := headers.get("authorization", None):
cashu_token = auth.split(" ")[1] if len(auth.split(" ")) > 1 else ""
logger.debug(
"Using Authorization header token",
extra={
"token_preview": cashu_token[:20] + "..."
if len(cashu_token) > 20
else cashu_token
},
)
else:
logger.error("No authentication token provided")
raise HTTPException(status_code=401, detail="Unauthorized")
# Handle empty token
if not cashu_token:
logger.error("Empty token provided")
raise HTTPException(
status_code=401,
detail={
"error": {
"message": "API key or Cashu token required",
"type": "invalid_request_error",
"code": "missing_api_key",
}
},
)
# Handle regular API keys (sk-*)
if cashu_token.startswith("sk-"):
return
try:
token_obj = deserialize_token_from_string(cashu_token)
except Exception:
# Invalid token format - let the auth system handle it
raise HTTPException(
status_code=401,
detail="Invalid authentication token format",
)
amount_msat = (
token_obj.amount if token_obj.unit == "msat" else token_obj.amount * 1000
)
if max_cost_for_model > amount_msat:
raise HTTPException(
status_code=413,
detail={
"reason": "Insufficient balance",
"amount_required_msat": max_cost_for_model,
"model": body.get("model", "unknown"),
"type": "minimum_balance_required",
},
)
async def get_max_cost_for_model(
model: str, session: AsyncSession | None = None
) -> int:
"""Get the maximum cost for a specific model."""
logger.debug(
"Getting max cost for model",
extra={
"model": model,
"fixed_pricing": settings.fixed_pricing,
"has_models": True,
},
)
# Fixed pricing: always use fixed_cost_per_request
if settings.fixed_pricing:
default_cost_msats = settings.fixed_cost_per_request * 1000
logger.debug(
"Using fixed cost pricing",
extra={"cost_msats": default_cost_msats, "model": model},
)
return max(settings.min_request_msat, default_cost_msats)
if session is None:
# Without a DB session, we can't resolve model pricing; fall back to fixed cost
fallback_msats = settings.fixed_cost_per_request * 1000
logger.warning(
"No DB session provided for model pricing; using fixed cost",
extra={"requested_model": model, "using_default_cost": fallback_msats},
)
return max(settings.min_request_msat, fallback_msats)
result = await session.exec(select(ModelRow.id)) # type: ignore
available_ids = [row[0] if isinstance(row, tuple) else row for row in result.all()]
if model not in available_ids:
# If no models or unknown model, fall back to fixed cost if provided, else minimal default
fallback_msats = settings.fixed_cost_per_request * 1000
logger.warning(
"Model not found in available models",
extra={
"requested_model": model,
"available_models": available_ids,
"using_default_cost": fallback_msats,
},
)
return max(settings.min_request_msat, fallback_msats)
row = await session.get(ModelRow, model)
if row and row.sats_pricing:
try:
sats = Pricing(**json.loads(row.sats_pricing)) # type: ignore
max_cost = sats.max_cost * 1000 * (1 - settings.tolerance_percentage / 100)
logger.debug(
"Found model-specific max cost",
extra={"model": model, "max_cost_msats": max_cost},
)
calculated_msats = int(max_cost)
return max(settings.min_request_msat, calculated_msats)
except Exception:
pass
logger.warning(
"Model pricing not found, using fixed cost",
extra={
"model": model,
"default_cost_msats": settings.fixed_cost_per_request * 1000,
},
)
return max(settings.min_request_msat, settings.fixed_cost_per_request * 1000)
async def calculate_discounted_max_cost(
max_cost_for_model: int, body: dict, session: AsyncSession | None = None
) -> int:
"""Calculate the discounted max cost for a request using model pricing when available."""
if settings.fixed_pricing or session is None:
return max_cost_for_model
model = body.get("model", "unknown")
model_pricing = await get_model_cost_info(model, session=session)
if not model_pricing:
return max_cost_for_model
tol = settings.tolerance_percentage
tol_factor = max(0.0, 1 - float(tol) / 100.0)
max_prompt_allowed_sats = model_pricing.max_prompt_cost * tol_factor
max_completion_allowed_sats = model_pricing.max_completion_cost * tol_factor
adjusted = max_cost_for_model
if messages := body.get("messages"):
prompt_tokens = estimate_tokens(messages)
estimated_prompt_delta_sats = (
max_prompt_allowed_sats - prompt_tokens * model_pricing.prompt
)
if estimated_prompt_delta_sats >= 0:
adjusted = adjusted - math.floor(estimated_prompt_delta_sats * 1000)
else:
adjusted = adjusted + math.ceil(-estimated_prompt_delta_sats * 1000)
max_tokens_raw = body.get("max_tokens", None)
if max_tokens_raw is not None:
try:
max_tokens_int = int(max_tokens_raw)
except (TypeError, ValueError):
logger.warning(
"Invalid max_tokens; ignoring in cost adjustment",
extra={"max_tokens": str(max_tokens_raw)[:64], "model": model},
)
else:
estimated_completion_delta_sats = (
max_completion_allowed_sats - max_tokens_int * model_pricing.completion
)
if estimated_completion_delta_sats >= 0:
adjusted = adjusted - math.floor(estimated_completion_delta_sats * 1000)
else:
adjusted = adjusted + math.ceil(-estimated_completion_delta_sats * 1000)
logger.debug(
"Discounted max cost computed",
extra={
"model": model,
"original_msats": max_cost_for_model,
"adjusted_msats": adjusted,
"tolerance_pct": tol,
},
)
return max(0, adjusted)
def estimate_tokens(messages: list) -> int:
return len(str(messages)) // 3
async def get_model_cost_info(
model_id: str, session: AsyncSession | None = None
) -> Pricing | None:
if not model_id or model_id == "unknown":
return None
if session is None:
return None
row = await session.get(ModelRow, model_id)
if row and row.sats_pricing:
try:
return Pricing(**json.loads(row.sats_pricing)) # type: ignore
except Exception:
return None
return None
def create_error_response(
error_type: str,
message: str,
status_code: int,
request: Request,
token: str | None = None,
) -> Response:
"""Create a standardized error response."""
return Response(
content=json.dumps(
{
"error": {
"message": message,
"type": error_type,
"code": status_code,
},
"request_id": getattr(request.state, "request_id", "unknown"),
}
),
status_code=status_code,
media_type="application/json",
headers={"X-Cashu": token} if token else {},
)
def prepare_upstream_headers(request_headers: dict) -> dict:
"""Prepare headers for upstream request, removing sensitive/problematic ones."""
upstream_api_key = settings.upstream_api_key
logger.debug(
"Preparing upstream headers",
extra={
"original_headers_count": len(request_headers),
"has_upstream_api_key": bool(upstream_api_key),
},
)
headers = dict(request_headers)
# Remove headers that shouldn't be forwarded
removed_headers = []
for header in [
"host",
"content-length",
"refund-lnurl",
"key-expiry-time",
"x-cashu",
]:
if headers.pop(header, None) is not None:
removed_headers.append(header)
# Handle authorization
if upstream_api_key:
headers["Authorization"] = f"Bearer {upstream_api_key}"
if headers.pop("authorization", None) is not None:
removed_headers.append("authorization (replaced with upstream key)")
else:
for auth_header in ["Authorization", "authorization"]:
if headers.pop(auth_header, None) is not None:
removed_headers.append(auth_header)
logger.debug(
"Headers prepared for upstream",
extra={
"final_headers_count": len(headers),
"removed_headers": removed_headers,
"added_upstream_auth": bool(upstream_api_key),
},
)
return headers
def prepare_upstream_params(
path: str, query_params: Mapping[str, str] | None
) -> dict[str, str]:
"""Prepare query params for upstream request, optionally adding api-version for chat/completions."""
params: dict[str, str] = dict(query_params or {})
chat_api_version = settings.chat_completions_api_version
if path.endswith("chat/completions") and chat_api_version:
params["api-version"] = chat_api_version
return params