feat: Refactor metrics/make API use binaries (#2735)

## What ❔

Add metric-emitting middleware for ExternalProofIntegrationAPI
Make API return binaries/allow uploading binaries for verification

## Why ❔

For better UX

## Checklist

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<!-- For draft PRs check the boxes as you complete them. -->

- [ ] PR title corresponds to the body of PR (we generate changelog
entries from PRs).
- [ ] Tests for the changes have been added / updated.
- [ ] Documentation comments have been added / updated.
- [ ] Code has been formatted via `zk fmt` and `zk lint`.

core/lib/prover_interface/src/api.rs

@@ -65,9 +65,6 @@ pub enum SubmitProofRequest {
     SkippedProofGeneration,
 }
 
-#[derive(Debug, Serialize, Deserialize)]
-pub struct OptionalProofGenerationDataRequest(pub Option<L1BatchNumber>);
-
 #[derive(Debug, Serialize, Deserialize)]
 pub struct VerifyProofRequest(pub Box<L1BatchProofForL1>);
 

core/node/external_proof_integration_api/Cargo.toml

@@ -11,7 +11,7 @@ keywords.workspace = true
 categories.workspace = true
 
 [dependencies]
-axum.workspace = true
+axum = { workspace = true, features = ["multipart"] }
 tracing.workspace = true
 zksync_prover_interface.workspace = true
 zksync_basic_types.workspace = true

core/node/external_proof_integration_api/src/lib.rs

@@ -1,19 +1,28 @@
 mod error;
 mod metrics;
+mod middleware;
 mod processor;
 
 use std::{net::SocketAddr, sync::Arc};
 
 use anyhow::Context;
-use axum::{extract::Path, routing::post, Json, Router};
+use axum::{
+    extract::{Multipart, Path, Request},
+    middleware::Next,
+    routing::{get, post},
+    Router,
+};
 use tokio::sync::watch;
 use zksync_basic_types::commitment::L1BatchCommitmentMode;
 use zksync_config::configs::external_proof_integration_api::ExternalProofIntegrationApiConfig;
 use zksync_dal::{ConnectionPool, Core};
 use zksync_object_store::ObjectStore;
-use zksync_prover_interface::api::{OptionalProofGenerationDataRequest, VerifyProofRequest};
 
-use crate::processor::Processor;
+use crate::{
+    metrics::{CallOutcome, Method},
+    middleware::MetricsMiddleware,
+    processor::Processor,
+};
 
 pub async fn run_server(
     config: ExternalProofIntegrationApiConfig,
@@ -23,7 +32,7 @@ pub async fn run_server(
     mut stop_receiver: watch::Receiver<bool>,
 ) -> anyhow::Result<()> {
     let bind_address = SocketAddr::from(([0, 0, 0, 0], config.http_port));
-    tracing::debug!("Starting external prover API server on {bind_address}");
+    tracing::info!("Starting external prover API server on {bind_address}");
     let app = create_router(blob_store, connection_pool, commitment_mode).await;
 
     let listener = tokio::net::TcpListener::bind(bind_address)
@@ -50,25 +59,45 @@ async fn create_router(
     let mut processor =
         Processor::new(blob_store.clone(), connection_pool.clone(), commitment_mode);
     let verify_proof_processor = processor.clone();
+    let specific_proof_processor = processor.clone();
+
+    let middleware_factory = |method: Method| {
+        axum::middleware::from_fn(move |req: Request, next: Next| async move {
+            let middleware = MetricsMiddleware::new(method);
+            let response = next.run(req).await;
+            let outcome = match response.status().is_success() {
+                true => CallOutcome::Success,
+                false => CallOutcome::Failure,
+            };
+            middleware.observe(outcome);
+            response
+        })
+    };
+
     Router::new()
         .route(
             "/proof_generation_data",
-            post(
-                // we use post method because the returned data is not idempotent,
-                // i.e we return different result on each call.
-                move |payload: Json<OptionalProofGenerationDataRequest>| async move {
-                    processor.get_proof_generation_data(payload).await
-                },
-            ),
+            get(move || async move { processor.get_proof_generation_data().await })
+                .layer(middleware_factory(Method::GetLatestProofGenerationData)),
+        )
+        .route(
+            "/proof_generation_data/:l1_batch_number",
+            get(move |l1_batch_number: Path<u32>| async move {
+                specific_proof_processor
+                    .proof_generation_data_for_existing_batch(l1_batch_number)
+                    .await
+            })
+            .layer(middleware_factory(Method::GetSpecificProofGenerationData)),
         )
         .route(
             "/verify_proof/:l1_batch_number",
             post(
-                move |l1_batch_number: Path<u32>, payload: Json<VerifyProofRequest>| async move {
+                move |l1_batch_number: Path<u32>, multipart: Multipart| async move {
                     verify_proof_processor
-                        .verify_proof(l1_batch_number, payload)
+                        .verify_proof(l1_batch_number, multipart)
                         .await
                 },
-            ),
+            )
+            .layer(middleware_factory(Method::VerifyProof)),
         )
 }

core/node/external_proof_integration_api/src/metrics.rs

@@ -1,6 +1,5 @@
 use std::time::Duration;
 
-use tokio::time::Instant;
 use vise::{EncodeLabelSet, EncodeLabelValue, Histogram, LabeledFamily, Metrics};
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, EncodeLabelSet, EncodeLabelValue)]
@@ -25,31 +24,5 @@ pub(crate) struct ProofIntegrationApiMetrics {
     pub call_latency: LabeledFamily<(Method, CallOutcome), Histogram<Duration>, 2>,
 }
 
-pub(crate) struct MethodCallGuard {
-    method_type: Method,
-    outcome: CallOutcome,
-    started_at: Instant,
-}
-
-impl MethodCallGuard {
-    pub(crate) fn new(method_type: Method) -> Self {
-        MethodCallGuard {
-            method_type,
-            outcome: CallOutcome::Failure,
-            started_at: Instant::now(),
-        }
-    }
-
-    pub(crate) fn mark_successful(&mut self) {
-        self.outcome = CallOutcome::Success;
-    }
-}
-
-impl Drop for MethodCallGuard {
-    fn drop(&mut self) {
-        METRICS.call_latency[&(self.method_type, self.outcome)].observe(self.started_at.elapsed());
-    }
-}
-
 #[vise::register]
 pub(crate) static METRICS: vise::Global<ProofIntegrationApiMetrics> = vise::Global::new();

core/node/external_proof_integration_api/src/middleware.rs

@@ -0,0 +1,22 @@
+use tokio::time::Instant;
+
+use crate::metrics::{CallOutcome, Method, METRICS};
+
+#[derive(Debug)]
+pub(crate) struct MetricsMiddleware {
+    method: Method,
+    started_at: Instant,
+}
+
+impl MetricsMiddleware {
+    pub fn new(method: Method) -> MetricsMiddleware {
+        MetricsMiddleware {
+            method,
+            started_at: Instant::now(),
+        }
+    }
+
+    pub fn observe(&self, outcome: CallOutcome) {
+        METRICS.call_latency[&(self.method, outcome)].observe(self.started_at.elapsed());
+    }
+}