From a69d199fab9a230fd5cd1bd546ab6471ef69eb2e Mon Sep 17 00:00:00 2001
From: jwinterm <johnwmurphy@gmail.com>
Date: Mon, 9 Mar 2026 10:27:47 -0400
Subject: [PATCH] Switch rate provider from CoinGecko to Kraken

Kraken public API is free and doesn't require an API key.
Supports XMR/USD and XMR/EUR pairs.
---
 .env.example       |  2 +-
 api/.env.example   |  2 +-
 api/app/config.py  |  2 +-
 api/app/rates.py   | 44 +++++++++++++++++++++++---------------------
 docker-compose.yml |  2 +-
 5 files changed, 27 insertions(+), 25 deletions(-)

diff --git a/.env.example b/.env.example
index f8f0120..8564495 100644
--- a/.env.example
+++ b/.env.example
@@ -10,7 +10,7 @@ BACKUP_RETENTION_DAYS=7
 # API authentication
 API_KEYS=dev-key-1
 API_KEY_ENCRYPTION_KEY=replace-with-fernet-key
-COINGECKO_API_KEY=
+RATE_PROVIDER=kraken
 INVOICE_RECONCILE_INTERVAL_SECONDS=30
 
 # Founder donation wallet (view-only)
diff --git a/api/.env.example b/api/.env.example
index 13f58b5..e82e3af 100644
--- a/api/.env.example
+++ b/api/.env.example
@@ -1,6 +1,6 @@
 DATABASE_URL=postgresql://xmrcheckout:xmrcheckout@localhost:5432/xmrcheckout
 API_KEYS=change-me-1,change-me-2
-COINGECKO_API_KEY=
+RATE_PROVIDER=kraken
 INVOICE_RECONCILE_INTERVAL_SECONDS=30
 FOUNDER_PAYMENT_ADDRESS=
 FOUNDER_VIEW_KEY=
diff --git a/api/app/config.py b/api/app/config.py
index d2be15e..b64812f 100644
--- a/api/app/config.py
+++ b/api/app/config.py
@@ -29,7 +29,7 @@ INVOICE_DEFAULT_EXPIRY_HOURS = int(os.getenv("INVOICE_DEFAULT_EXPIRY_HOURS", "1"
 LATE_PAYMENT_LOOKBACK_HOURS = int(os.getenv("LATE_PAYMENT_LOOKBACK_HOURS", "48"))
 DONATION_EXPIRY_MINUTES = int(os.getenv("DONATION_EXPIRY_MINUTES", "30"))
 DONATION_ACTIVE_INVOICE_LIMIT = int(os.getenv("DONATION_ACTIVE_INVOICE_LIMIT", "25"))
-COINGECKO_API_KEY = os.getenv("COINGECKO_API_KEY", "")
+RATE_PROVIDER = os.getenv("RATE_PROVIDER", "kraken")
 DONATIONS_ENABLED = _get_bool_env("DONATIONS_ENABLED", False)
 
 MONERO_WALLET_RPC_URLS = [
diff --git a/api/app/rates.py b/api/app/rates.py
index ae969e0..ce14e59 100644
--- a/api/app/rates.py
+++ b/api/app/rates.py
@@ -9,12 +9,16 @@ from typing import Any
 
 import requests
 
-from .config import COINGECKO_API_KEY
-
-COINGECKO_URL = "https://api.coingecko.com/api/v3/simple/price"
-COINGECKO_SOURCE = "coingecko"
+KRAKEN_TICKER_URL = "https://api.kraken.com/0/public/Ticker"
+KRAKEN_SOURCE = "kraken"
 RATE_TTL_SECONDS = 60
 
+# Kraken pair names for XMR against common fiat currencies
+_KRAKEN_PAIRS: dict[str, str] = {
+    "usd": "XXMRZUSD",
+    "eur": "XXMRZEUR",
+}
+
 
 @dataclass(frozen=True)
 class QuoteResult:
@@ -32,34 +36,32 @@ _cached_at: float | None = None
 def get_xmr_rate(currency: str) -> QuoteResult:
     global _cached_quote, _cached_at
     normalized_currency = currency.strip().lower()
-    if not COINGECKO_API_KEY:
-        raise RuntimeError("CoinGecko API key is not configured")
+
+    pair = _KRAKEN_PAIRS.get(normalized_currency)
+    if pair is None:
+        raise ValueError(f"Unsupported fiat currency: {currency} (supported: {', '.join(_KRAKEN_PAIRS)})")
 
     with _cache_lock:
         if _cached_quote and _cached_at:
             if time.monotonic() - _cached_at < RATE_TTL_SECONDS:
                 return _cached_quote
 
-    params = {
-        "vs_currencies": normalized_currency,
-        "ids": "monero",
-        "x_cg_demo_api_key": COINGECKO_API_KEY,
-    }
-    response = requests.get(COINGECKO_URL, params=params, timeout=5)
+    response = requests.get(KRAKEN_TICKER_URL, params={"pair": pair}, timeout=5)
     response.raise_for_status()
     data: dict[str, Any] = response.json()
-    rate_value = (
-        data.get("monero", {}).get(normalized_currency)
-        if isinstance(data, dict)
-        else None
-    )
-    if rate_value is None:
-        raise ValueError("Unsupported fiat currency at this time")
-    rate = Decimal(str(rate_value))
+    if data.get("error"):
+        raise RuntimeError(f"Kraken API error: {data['error']}")
+    result = data.get("result", {})
+    ticker = result.get(pair, {})
+    # 'c' is the last trade closed: [price, lot-volume]
+    last_price = ticker.get("c", [None])[0]
+    if last_price is None:
+        raise ValueError("Could not get XMR rate from Kraken")
+    rate = Decimal(str(last_price))
     quote = QuoteResult(
         rate=rate,
         currency=normalized_currency.upper(),
-        source=COINGECKO_SOURCE,
+        source=KRAKEN_SOURCE,
         quoted_at=datetime.now(timezone.utc),
     )
     with _cache_lock:
diff --git a/docker-compose.yml b/docker-compose.yml
index d5b0aa1..e9fd0b9 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -22,7 +22,7 @@ services:
       DATABASE_URL: ${DATABASE_URL}
       API_KEYS: ${API_KEYS}
       API_KEY_ENCRYPTION_KEY: ${API_KEY_ENCRYPTION_KEY}
-      COINGECKO_API_KEY: ${COINGECKO_API_KEY}
+      RATE_PROVIDER: ${RATE_PROVIDER:-kraken}
       FOUNDER_PAYMENT_ADDRESS: ${FOUNDER_PAYMENT_ADDRESS}
       FOUNDER_VIEW_KEY: ${FOUNDER_VIEW_KEY}
       DONATIONS_ENABLED: ${DONATIONS_ENABLED:-false}