feat: rework handle of ETH price

eth_validator_watcher/coinbase.py

@@ -1,33 +1,31 @@
-"""Contains the Coinbase class, which is responsible for fetching the ETH/USD"""
+"""Helper to fetch the ETH/USD"""
 
-from prometheus_client import Gauge
+from cachetools import func
 from pydantic import parse_obj_as
 from requests import Session
 
 from .models import CoinbaseTrade
 
+
 URL = "https://api.pro.coinbase.com/products/ETH-USD/trades"
-metric_eth_usd_gauge = Gauge("eth_usd", "ETH/USD conversion rate")
-
-
-class Coinbase:
-    """Coinbase abstraction."""
-
-    def __init__(self) -> None:
-        """Coinbase"""
-        self.__http = Session()
-
-    def emit_eth_usd_conversion_rate(self) -> None:
-        """Emit the ETH/USD conversion rate to Prometheus Gauge.
-
-        If any error, fails silently.
-        """
-        try:
-            response = self.__http.get(URL, params=dict(limit=1))
-            trades_dict = response.json()
-            trades = parse_obj_as(list[CoinbaseTrade], trades_dict)
-            trade, *_ = trades
-            metric_eth_usd_gauge.set(trade.price)
-        except:
-            # This feature is totally optional, so if it fails, we just return 0
-            pass
+
+
+@func.ttl_cache(ttl=600)
+def get_current_eth_price() -> float:
+    """Get the current ETH price in USD.
+
+    Returns:
+    --------
+    float
+    """
+    try:
+        response = Session().get(URL, params=dict(limit=1))
+        trades_dict = response.json()
+        trades = parse_obj_as(list[CoinbaseTrade], trades_dict)
+        trade, *_ = trades
+    except:
+        # This feature is totally optional, so if it fails, we just
+        # return 0.0.
+        return 0.0
+
+    return trade.price

eth_validator_watcher/entrypoint_v2.py

@@ -12,6 +12,7 @@
 import typer
 import time
 
+from .coinbase import  get_current_eth_price
 from .beacon import Beacon
 from .config import load_config, WatchedKeyConfig
 from .metrics import get_prometheus_metrics
@@ -156,6 +157,7 @@ def _update_metrics(self, watched_validators: WatchedValidators, epoch: int, slo
         """
         self._metrics.eth_epoch.set(epoch)
         self._metrics.eth_slot.set(slot)
+        self._metrics.eth_current_price.set(get_current_eth_price())
 
         # We iterate once on the validator set to optimize CPU as
         # there is a log of entries here, this makes code here a bit

eth_validator_watcher/metrics.py

@@ -14,6 +14,7 @@ class PrometheusMetrics:
     """
     eth_slot: Gauge
     eth_epoch: Gauge
+    eth_current_price: Gauge
 
     eth_validator_status_count: Gauge
     eth_suboptimal_sources_rate: Gauge
@@ -39,6 +40,7 @@ def get_prometheus_metrics() -> PrometheusMetrics:
         _metrics = PrometheusMetrics(
             eth_slot=Gauge("eth_slot", "Current slot"),
             eth_epoch=Gauge("eth_epoch", "Current epoch"),
+            eth_current_price=Gauge("eth_current_price", "Current price of ETH in USD"),
             eth_validator_status_count=Gauge("eth_validator_status_count", "Validator status count", ['scope', 'status']),
             eth_suboptimal_sources_rate=Gauge("eth_suboptimal_sources_rate", "Suboptimal sources rate", ['scope']),
             eth_suboptimal_targets_rate=Gauge("eth_suboptimal_targets_rate", "Suboptimal targets rate", ['scope']),

pyproject.toml

@@ -18,6 +18,7 @@ tenacity = "^8.2.2"
 pyyaml = "^6.0.1"
 pydantic-yaml = "^1.2.0"
 pydantic-settings = "^2.1.0"
+cachetools = "^5.3.3"
 
 [tool.poetry.group.dev.dependencies]
 mypy = "^1.2.0"