DO NOT MERGE: Test RPC method for object fetching

crates/sc-consensus-subspace-rpc/Cargo.toml

@@ -16,6 +16,7 @@ targets = ["x86_64-unknown-linux-gnu"]
 async-oneshot = "0.5.9"
 futures = "0.3.29"
 futures-timer = "3.0.3"
+hex = "0.4.3"
 jsonrpsee = { version = "0.23.2", features = ["server", "macros"] }
 parity-scale-codec = "3.6.12"
 parking_lot = "0.12.2"
@@ -25,6 +26,7 @@ sc-consensus-subspace = { version = "0.1.0", path = "../sc-consensus-subspace" }
 sc-rpc = { git = "https://github.com/subspace/polkadot-sdk", rev = "5626154d0781ac9a6ffd5a6207ed237f425ae631" }
 sc-rpc-api = { git = "https://github.com/subspace/polkadot-sdk", rev = "5626154d0781ac9a6ffd5a6207ed237f425ae631" }
 sc-utils = { git = "https://github.com/subspace/polkadot-sdk", rev = "5626154d0781ac9a6ffd5a6207ed237f425ae631" }
+serde = "1.0.206"
 sp-api = { git = "https://github.com/subspace/polkadot-sdk", rev = "5626154d0781ac9a6ffd5a6207ed237f425ae631" }
 sp-consensus = { git = "https://github.com/subspace/polkadot-sdk", rev = "5626154d0781ac9a6ffd5a6207ed237f425ae631" }
 sp-consensus-subspace = { version = "0.1.0", path = "../sp-consensus-subspace" }
@@ -37,6 +39,7 @@ subspace-core-primitives = { version = "0.1.0", path = "../subspace-core-primiti
 subspace-erasure-coding = { version = "0.1.0", path = "../subspace-erasure-coding" }
 subspace-farmer-components = { version = "0.1.0", path = "../subspace-farmer-components" }
 subspace-networking = { version = "0.1.0", path = "../subspace-networking" }
+subspace-object-fetching = { version = "0.1.0", path = "../subspace-object-fetching" }
 subspace-rpc-primitives = { version = "0.1.0", path = "../subspace-rpc-primitives" }
 thiserror = "1.0.63"
 tracing = "0.1.40"

crates/sc-consensus-subspace-rpc/src/lib.rs

@@ -113,6 +113,23 @@ impl From<Error> for ErrorObjectOwned {
     }
 }
 
+/// Hex-encoded object data.
+#[derive(
+    Debug,
+    Clone,
+    PartialEq,
+    Eq,
+    Ord,
+    PartialOrd,
+    Hash,
+    Encode,
+    Decode,
+    serde::Serialize,
+    serde::Deserialize,
+)]
+#[serde(transparent)]
+pub struct HexData(#[serde(with = "hex")] pub Vec<u8>);
+
 /// Provides rpc methods for interacting with Subspace.
 #[rpc(client, server)]
 pub trait SubspaceRpcApi {
@@ -186,6 +203,12 @@ pub trait SubspaceRpcApi {
         item = GlobalObjectMapping,
     )]
     fn subscribe_filtered_object_mappings(&self, hashes: Vec<Blake3HashHex>);
+
+    #[method(name = "subspace_fetchArchivedObject")]
+    async fn fetch_archived_object(
+        &self,
+        mapping: subspace_core_primitives::objects::GlobalObject,
+    ) -> Result<HexData, Error>;
 }
 
 #[derive(Default)]
@@ -249,6 +272,9 @@ where
     pub kzg: Kzg,
     /// Erasure coding instance
     pub erasure_coding: ErasureCoding,
+    /// DSN object piece getter
+    pub object_piece_getter:
+        Arc<dyn subspace_object_fetching::ObjectPieceGetter + Send + Sync + 'static>,
 }
 
 /// Implements the [`SubspaceRpcApiServer`] trait for interacting with Subspace.
@@ -280,6 +306,7 @@ where
     erasure_coding: ErasureCoding,
     deny_unsafe: DenyUnsafe,
     _block: PhantomData<Block>,
+    object_fetcher: subspace_object_fetching::ObjectFetcher,
 }
 
 /// [`SubspaceRpc`] is used for notifying subscribers about arrival of new slots and for
@@ -338,6 +365,9 @@ where
             erasure_coding: config.erasure_coding,
             deny_unsafe: config.deny_unsafe,
             _block: PhantomData,
+            object_fetcher: subspace_object_fetching::ObjectFetcher {
+                piece_getter: config.object_piece_getter,
+            },
         })
     }
 }
@@ -930,4 +960,22 @@ where
             pipe_from_stream(pending, mapping_stream).boxed(),
         );
     }
+
+    async fn fetch_archived_object(
+        &self,
+        mapping: subspace_core_primitives::objects::GlobalObject,
+    ) -> Result<HexData, Error> {
+        self.deny_unsafe.check_if_safe()?;
+
+        let object = self
+            .object_fetcher
+            .fetch_object(mapping)
+            .await
+            .map_err(|error| {
+                error!("Failed to fetch object: {}", error);
+                Error::StringError(format!("Failed to fetch object: {error}"))
+            })?;
+
+        Ok(HexData(object))
+    }
 }

crates/subspace-service/Cargo.toml

@@ -87,6 +87,7 @@ subspace-archiving = { version = "0.1.0", path = "../subspace-archiving" }
 subspace-core-primitives = { version = "0.1.0", path = "../subspace-core-primitives" }
 subspace-erasure-coding = { version = "0.1.0", path = "../subspace-erasure-coding" }
 subspace-networking = { version = "0.1.0", path = "../subspace-networking" }
+subspace-object-fetching = { version = "0.1.0", path = "../subspace-object-fetching" }
 subspace-proof-of-space = { version = "0.1.0", path = "../subspace-proof-of-space" }
 subspace-runtime-primitives = { version = "0.1.0", path = "../subspace-runtime-primitives" }
 substrate-frame-rpc-system = { git = "https://github.com/subspace/polkadot-sdk", rev = "5626154d0781ac9a6ffd5a6207ed237f425ae631" }

crates/subspace-service/src/lib.rs

@@ -1199,6 +1199,15 @@ where
     // We replace the Substrate implementation of metrics server with our own.
     config.base.prometheus_config.take();
 
+    let object_piece_getter = Arc::new(PieceProvider::new(
+        node.clone(),
+        Some(SegmentCommitmentPieceValidator::new(
+            node.clone(),
+            subspace_link.kzg().clone(),
+            segment_headers_store.clone(),
+        )),
+    ));
+
     let rpc_handlers = task_spawner::spawn_tasks(SpawnTasksParams {
         network: network_service.clone(),
         client: client.clone(),
@@ -1231,6 +1240,7 @@ where
                     kzg: subspace_link.kzg().clone(),
                     erasure_coding: subspace_link.erasure_coding().clone(),
                     backend: backend.clone(),
+                    object_piece_getter: object_piece_getter.clone(),
                 };
 
                 rpc::create_full(deps).map_err(Into::into)

crates/subspace-service/src/rpc.rs

@@ -85,6 +85,9 @@ where
     pub erasure_coding: ErasureCoding,
     /// Backend used by the node.
     pub backend: Arc<B>,
+    /// DSN object piece getter
+    pub object_piece_getter:
+        Arc<dyn subspace_object_fetching::ObjectPieceGetter + Send + Sync + 'static>,
 }
 
 /// Instantiate all full RPC extensions.
@@ -127,6 +130,7 @@ where
         kzg,
         erasure_coding,
         backend,
+        object_piece_getter,
     } = deps;
 
     let chain_name = chain_spec.name().to_string();
@@ -150,6 +154,7 @@ where
             kzg,
             erasure_coding,
             deny_unsafe,
+            object_piece_getter,
         })?
         .into_rpc(),
     )?;