refactor: add inject attestation signer

Signed-off-by: Gustavo Inacio <[email protected]>

Author: gusinacio

crates/service/src/middleware.rs

@@ -3,6 +3,7 @@
 
 pub mod auth;
 mod inject_allocation;
+mod inject_attestation_signer;
 mod inject_context;
 mod inject_deployment;
 mod inject_labels;

crates/service/src/middleware/inject_attestation_signer.rs

@@ -0,0 +1,36 @@
+// Copyright 2023-, Edge & Node, GraphOps, and Semiotic Labs.
+// SPDX-License-Identifier: Apache-2.0
+
+use alloy::primitives::Address;
+use axum::{
+    extract::{Request, State},
+    middleware::Next,
+    response::Response,
+};
+use indexer_attestation::AttestationSigner;
+use std::collections::HashMap;
+use tokio::sync::watch;
+
+use super::Allocation;
+
+#[derive(Clone)]
+pub struct AttestationState {
+    pub attestation_signers: watch::Receiver<HashMap<Address, AttestationSigner>>,
+}
+
+/// injects the attestation signer to be used in the attestation
+///
+/// Needs Allocation Extension
+pub async fn signer_middleware(
+    State(state): State<AttestationState>,
+    mut request: Request,
+    next: Next,
+) -> Response {
+    if let Some(Allocation(allocation_id)) = request.extensions().get::<Allocation>() {
+        if let Some(signer) = state.attestation_signers.borrow().get(allocation_id) {
+            request.extensions_mut().insert(signer.clone());
+        }
+    }
+
+    next.run(request).await
+}