Move instrumented gas estimator into shared (#413)

* Convert gas estimator metrics to MetricStorage

* Move InstrumentedGasPriceEstimator into shared

crates/orderbook/src/lib.rs

@@ -2,7 +2,6 @@ pub mod api;
 pub mod arguments;
 pub mod database;
 pub mod fee_subsidy;
-pub mod gas_price;
 pub mod metrics;
 pub mod order_quoting;
 pub mod order_validation;

crates/orderbook/src/main.rs

@@ -10,7 +10,6 @@ use orderbook::{
     fee_subsidy::{
         config::FeeSubsidyConfiguration, cow_token::CowSubsidy, FeeSubsidies, FeeSubsidizing,
     },
-    gas_price::InstrumentedGasEstimator,
     metrics::Metrics,
     order_quoting::{Forget, OrderQuoter, QuoteHandler, QuoteStoring},
     order_validation::{OrderValidator, SignatureConfiguration},
@@ -35,6 +34,7 @@ use shared::{
     balancer_sor_api::DefaultBalancerSorApi,
     baseline_solver::BaseTokens,
     current_block::current_block_stream,
+    gas_price::InstrumentedGasEstimator,
     http_solver::{DefaultHttpSolverApi, Objective, SolverConfig},
     maintenance::ServiceMaintenance,
     metrics::{serve_metrics, DEFAULT_METRICS_PORT},
@@ -163,7 +163,6 @@ async fn main() {
         )
         .await
         .expect("failed to create gas price estimator"),
-        metrics.clone(),
     ));
 
     let baseline_sources = args.shared.baseline_sources.unwrap_or_else(|| {

crates/orderbook/src/metrics.rs

@@ -1,10 +1,7 @@
 use anyhow::Result;
-use gas_estimation::GasPrice1559;
-use prometheus::{Gauge, IntCounter, IntCounterVec, IntGauge, Opts};
+use prometheus::{IntCounter, IntCounterVec, IntGauge, Opts};
 
 pub struct Metrics {
-    /// Gas estimate metrics
-    gas_price: Gauge,
     native_price_cache: IntCounterVec,
     // auction metrics
     auction_creations: IntCounter,
@@ -18,10 +15,6 @@ impl Metrics {
     pub fn new() -> Result<Self> {
         let registry = global_metrics::get_metrics_registry();
 
-        let opts = Opts::new("gas_price", "Gas price estimate over time.");
-        let gas_price = Gauge::with_opts(opts).unwrap();
-        registry.register(Box::new(gas_price.clone()))?;
-
         let native_price_cache = IntCounterVec::new(
             Opts::new("native_price_cache", "Native price cache hit/miss counter."),
             &["result"],
@@ -59,7 +52,6 @@ impl Metrics {
         registry.register(Box::new(auction_price_estimate_timeouts.clone()))?;
 
         Ok(Self {
-            gas_price,
             native_price_cache,
             auction_creations,
             auction_solvable_orders,
@@ -89,12 +81,6 @@ impl crate::solvable_orders::AuctionMetrics for Metrics {
     }
 }
 
-impl crate::gas_price::Metrics for Metrics {
-    fn gas_price(&self, estimate: GasPrice1559) {
-        self.gas_price.set(estimate.effective_gas_price() / 1e9);
-    }
-}
-
 impl shared::price_estimation::native_price_cache::Metrics for Metrics {
     fn native_price_cache(&self, misses: usize, hits: usize) {
         self.native_price_cache

crates/orderbook/src/gas_price.rs → crates/shared/src/gas_price.rs

@@ -6,20 +6,23 @@
 
 use anyhow::Result;
 use gas_estimation::{GasPrice1559, GasPriceEstimating};
-use std::{sync::Arc, time::Duration};
+use std::time::Duration;
 
 /// An instrumented gas price estimator that wraps an inner one.
 pub struct InstrumentedGasEstimator<T> {
     inner: T,
-    metrics: Arc<dyn Metrics>,
+    metrics: &'static Metrics,
 }
 
 impl<T> InstrumentedGasEstimator<T>
 where
     T: GasPriceEstimating,
 {
-    pub fn new(inner: T, metrics: Arc<dyn Metrics>) -> Self {
-        Self { inner, metrics }
+    pub fn new(inner: T) -> Self {
+        Self {
+            inner,
+            metrics: Metrics::instance(global_metrics::get_metric_storage_registry()).unwrap(),
+        }
     }
 }
 
@@ -40,12 +43,15 @@ where
 
     async fn estimate(&self) -> Result<GasPrice1559> {
         let estimate = self.inner.estimate().await?;
-        self.metrics.gas_price(estimate);
+        self.metrics
+            .gas_price
+            .set(estimate.effective_gas_price() / 1e9);
         Ok(estimate)
     }
 }
 
-/// Gas estimator metrics.
-pub trait Metrics: Send + Sync + 'static {
-    fn gas_price(&self, estimate: GasPrice1559);
+#[derive(prometheus_metric_storage::MetricStorage)]
+struct Metrics {
+    /// Last measured gas price in gwei
+    gas_price: prometheus::Gauge,
 }

crates/shared/src/lib.rs

@@ -11,6 +11,7 @@ pub mod conversions;
 pub mod current_block;
 pub mod ethcontract_error;
 pub mod event_handling;
+pub mod gas_price;
 pub mod gas_price_estimation;
 pub mod http_client;
 pub mod http_solver;