btcusd price fetcher

proxy/price.py

@@ -0,0 +1,35 @@
+import os
+import httpx
+import asyncio
+
+# artifical spread to cover conversion fees
+EXCHANGE_FEE = os.environ.get("EXCHANGE_FEE", 1.005)  # 0.5% default
+
+
+async def kraken_btc_usd(client: httpx.AsyncClient) -> int:
+    api = "https://api.kraken.com/0/public/Ticker?pair=XBTUSD"
+    return int(float((await client.get(api)).json()["result"]["XXBTZUSD"]["c"][0]))
+
+
+async def coinbase_btc_usd(client: httpx.AsyncClient) -> int:
+    api = "https://api.coinbase.com/v2/prices/BTC-USD/spot"
+    return int(float((await client.get(api)).json()["data"]["amount"]))
+
+
+async def binance_btc_usdt(client: httpx.AsyncClient) -> int:
+    api = "https://api.binance.com/api/v3/ticker/price?symbol=BTCUSDT"
+    return int(float((await client.get(api)).json()["price"]))
+
+
+async def btc_usd_ask_price() -> int:
+    async with httpx.AsyncClient() as client:
+        return int(
+            max(
+                await asyncio.gather(
+                    kraken_btc_usd(client),
+                    coinbase_btc_usd(client),
+                    binance_btc_usdt(client),
+                )
+            )
+            * EXCHANGE_FEE
+        )