add into_v3_payload

crates/payload/builder/src/payload.rs

@@ -63,6 +63,13 @@ impl BuiltPayload {
 
     /// Converts the type into the response expected by `engine_getPayloadV2`
     pub fn into_v2_payload(self) -> ExecutionPayloadEnvelope {
+        let mut envelope: ExecutionPayloadEnvelope = self.into();
+        envelope.blobs_bundle = None;
+        envelope
+    }
+
+    /// Converts the type into the response expected by `engine_getPayloadV2`
+    pub fn into_v3_payload(self) -> ExecutionPayloadEnvelope {
         self.into()
     }
 }
@@ -75,6 +82,10 @@ impl From<BuiltPayload> for ExecutionPayload {
 }
 
 // V2 engine_getPayloadV2 response
+// TODO(rjected): we could improve this by wrapping envelope / payload types by version, so we can
+// have explicitly versioned return types for getPayload. Then BuiltPayload could essentially be a
+// builder for those types, and it would not be possible to e.g. return cancun fields for a
+// pre-cancun endpoint.
 impl From<BuiltPayload> for ExecutionPayloadEnvelope {
     fn from(value: BuiltPayload) -> Self {
         let BuiltPayload { block, fees, sidecars, .. } = value;

crates/rpc/rpc-engine-api/src/engine_api.rs

@@ -180,7 +180,7 @@ where
     ///
     /// Note:
     /// > Provider software MAY stop the corresponding build process after serving this call.
-    async fn get_payload_v2(
+    pub async fn get_payload_v2(
         &self,
         payload_id: PayloadId,
     ) -> EngineApiResult<ExecutionPayloadEnvelope> {
@@ -193,6 +193,26 @@ where
             .map(|payload| (*payload).clone().into_v2_payload())?)
     }
 
+    /// Returns the most recent version of the payload that is available in the corresponding
+    /// payload build process at the time of receiving this call.
+    ///
+    /// See also <https://github.com/ethereum/execution-apis/blob/fe8e13c288c592ec154ce25c534e26cb7ce0530d/src/engine/cancun.md#engine_getpayloadv3>
+    ///
+    /// Note:
+    /// > Provider software MAY stop the corresponding build process after serving this call.
+    pub async fn get_payload_v3(
+        &self,
+        payload_id: PayloadId,
+    ) -> EngineApiResult<ExecutionPayloadEnvelope> {
+        Ok(self
+            .inner
+            .payload_store
+            .resolve(payload_id)
+            .await
+            .ok_or(EngineApiError::UnknownPayload)?
+            .map(|payload| (*payload).clone().into_v3_payload())?)
+    }
+
     /// Returns the execution payload bodies by the range starting at `start`, containing `count`
     /// blocks.
     ///