docs: add comment on why we dont fail in absense

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

Author: gusinacio

crates/service/src/middleware/inject_receipt.rs

@@ -8,6 +8,10 @@ use crate::service::TapReceipt;
 
 /// Injects tap receipts in the extensions
 ///
+/// A request won't always have a receipt because they might be
+/// free queries.
+/// That's why we don't fail with 400.
+///
 /// This is useful to not deserialize multiple times the same receipt
 pub async fn receipt_middleware(mut request: Request, next: Next) -> Response {
     if let Ok(TypedHeader(receipt)) = request.extract_parts::<TypedHeader<TapReceipt>>().await {

crates/service/src/middleware/inject_sender.rs

@@ -34,6 +34,10 @@ impl From<Sender> for String {
 
 /// Injects the sender found from the signer in the receipt
 ///
+/// A request won't always have a receipt because they might be
+/// free queries.
+/// That's why we don't fail with 400.
+///
 /// Requires Receipt extension
 pub async fn sender_middleware(
     State(state): State<SenderState>,