change(rpc): Adds ignored jsonrequestobject argument to the getblocktemplate RPC (#5772)

* Adds ignored jsonrequestobject argument

* adds docs

returns an error for unsupported options

* returns an error when longpollid is provided

* comments out capabilities enum and uses Vec<String> instead

* fixes spelling mistake

* uncomments GetBlockTemplateCapability enum and uses allow(dead_code) instead

* adds UnknownCapability

* Apply suggestions from code review

Co-authored-by: teor <teor@riseup.net>

* adds derived traits.

* removes unused [allow(dead_code)]

* test invalid params error for block data

* add capablity to gbt vectors test

* reverts passing in default options to getblocktemplate request in vectors test

* adds a jsonrequestobject with an unknown capability to gbt acceptance test

Co-authored-by: teor <teor@riseup.net>

zebra-rpc/src/methods/get_block_template_rpcs.rs

@@ -33,8 +33,9 @@ use zebra_state::{ReadRequest, ReadResponse};
 use crate::methods::{
     best_chain_tip_height,
     get_block_template_rpcs::types::{
-        default_roots::DefaultRoots, get_block_template::GetBlockTemplate, hex_data::HexData,
-        submit_block, transaction::TransactionTemplate,
+        default_roots::DefaultRoots, get_block_template::GetBlockTemplate,
+        get_block_template_opts::GetBlockTemplateRequestMode, hex_data::HexData, submit_block,
+        transaction::TransactionTemplate,
     },
     GetBlockHash, MISSING_BLOCK_ERROR_CODE,
 };
@@ -42,7 +43,7 @@ use crate::methods::{
 pub mod config;
 pub mod constants;
 
-pub(crate) mod types;
+pub mod types;
 pub(crate) mod zip317;
 
 /// The max estimated distance to the chain tip for the getblocktemplate method.
@@ -113,7 +114,10 @@ pub trait GetBlockTemplateRpc {
     ///
     /// This rpc method is available only if zebra is built with `--features getblocktemplate-rpcs`.
     #[rpc(name = "getblocktemplate")]
-    fn get_block_template(&self) -> BoxFuture<Result<GetBlockTemplate>>;
+    fn get_block_template(
+        &self,
+        options: Option<types::get_block_template_opts::JsonParameters>,
+    ) -> BoxFuture<Result<GetBlockTemplate>>;
 
     /// Submits block to the node to be validated and committed.
     /// Returns the [`submit_block::Response`] for the operation, as a JSON string.
@@ -292,7 +296,10 @@ where
         .boxed()
     }
 
-    fn get_block_template(&self) -> BoxFuture<Result<GetBlockTemplate>> {
+    fn get_block_template(
+        &self,
+        options: Option<types::get_block_template_opts::JsonParameters>,
+    ) -> BoxFuture<Result<GetBlockTemplate>> {
         let network = self.network;
         let miner_address = self.miner_address;
 
@@ -303,6 +310,24 @@ where
 
         // Since this is a very large RPC, we use separate functions for each group of fields.
         async move {
+            if let Some(options) = options {
+                if options.data.is_some() || options.mode == GetBlockTemplateRequestMode::Proposal {
+                    return Err(Error {
+                        code: ErrorCode::InvalidParams,
+                        message: "\"proposal\" mode is currently unsupported by Zebra".to_string(),
+                        data: None,
+                    })
+                }
+
+                if options.longpollid.is_some() {
+                    return Err(Error {
+                        code: ErrorCode::InvalidParams,
+                        message: "long polling is currently unsupported by Zebra".to_string(),
+                        data: None,
+                    })
+                }
+            }
+
             let miner_address = miner_address.ok_or_else(|| Error {
                 code: ErrorCode::ServerError(0),
                 message: "configure mining.miner_address in zebrad.toml \

zebra-rpc/src/methods/get_block_template_rpcs/types.rs

@@ -1,7 +1,8 @@
 //! Types used in mining RPC methods.
 
-pub(crate) mod default_roots;
-pub(crate) mod get_block_template;
-pub(crate) mod hex_data;
-pub(crate) mod submit_block;
-pub(crate) mod transaction;
+pub mod default_roots;
+pub mod get_block_template;
+pub mod get_block_template_opts;
+pub mod hex_data;
+pub mod submit_block;
+pub mod transaction;

zebra-rpc/src/methods/get_block_template_rpcs/types/get_block_template_opts.rs

@@ -0,0 +1,91 @@
+//! Parameter types for the `getblocktemplate` RPC.
+
+use super::hex_data::HexData;
+
+/// Defines whether the RPC method should generate a block template or attempt to validate a block proposal.
+/// `Proposal` mode is currently unsupported and will return an error.
+#[derive(Clone, Debug, serde::Deserialize, PartialEq, Eq)]
+#[serde(rename_all = "lowercase")]
+pub enum GetBlockTemplateRequestMode {
+    /// Indicates a request for a block template.
+    Template,
+
+    /// Indicates a request to validate block data.
+    /// Currently unsupported and will return an error.
+    Proposal,
+}
+
+impl Default for GetBlockTemplateRequestMode {
+    fn default() -> Self {
+        Self::Template
+    }
+}
+
+/// Valid `capabilities` values that indicate client-side support.
+#[derive(Clone, Debug, serde::Deserialize, PartialEq, Eq)]
+#[serde(rename_all = "lowercase")]
+pub enum GetBlockTemplateCapability {
+    /// Long Polling support.
+    /// Currently ignored by zebra.
+    LongPoll,
+
+    /// Information for coinbase transaction, default template data with the `coinbasetxn` field.
+    /// Currently ignored by zebra.
+    CoinbaseTxn,
+
+    /// Coinbase value, template response provides a `coinbasevalue` field and omits `coinbasetxn` field.
+    /// Currently ignored by zebra.
+    CoinbaseValue,
+
+    /// Components of the coinbase transaction.
+    /// Currently ignored by zebra.
+    CoinbaseAux,
+
+    /// Currently ignored by zcashd and zebra.
+    Proposal,
+
+    /// Currently ignored by zcashd and zebra.
+    ServerList,
+
+    /// Currently ignored by zcashd and zebra.
+    WorkId,
+
+    /// Unknown capability to fill in for mutations.
+    // TODO: Fill out valid mutations capabilities.
+    #[serde(other)]
+    UnknownCapability,
+}
+
+/// Optional argument `jsonrequestobject` for `getblocktemplate` RPC request.
+///
+/// The `data` field must be provided in `proposal` mode, and must be omitted in `template` mode.
+/// All other fields are optional.
+#[derive(Clone, Debug, PartialEq, Eq, serde::Deserialize, Default)]
+pub struct JsonParameters {
+    /// Must be set to "template" or omitted, as "proposal" mode is currently unsupported.
+    ///
+    /// Defines whether the RPC method should generate a block template or attempt to
+    /// validate block data, checking against all of the server's usual acceptance rules
+    /// (excluding the check for a valid proof-of-work).
+    // TODO: Support `proposal` mode.
+    #[serde(default)]
+    pub mode: GetBlockTemplateRequestMode,
+
+    /// Must be omitted as "proposal" mode is currently unsupported.
+    ///
+    /// Hex-encoded block data to be validated and checked against the server's usual acceptance rules
+    /// (excluding the check for a valid proof-of-work) when `mode` is set to `proposal`.
+    pub data: Option<HexData>,
+
+    /// A list of client-side supported capability features
+    // TODO: Fill out valid mutations capabilities.
+    #[serde(default)]
+    pub capabilities: Vec<GetBlockTemplateCapability>,
+
+    /// An id to wait for, in zcashd this is the tip hash and an internal counter.
+    ///
+    /// If provided, the RPC response is delayed until the mempool or chain tip block changes.
+    ///
+    /// Currently unsupported and ignored by Zebra.
+    pub longpollid: Option<String>,
+}

zebra-rpc/src/methods/get_block_template_rpcs/types/hex_data.rs

@@ -2,5 +2,5 @@
 //! for the `submitblock` RPC method.
 
 /// Deserialize hex-encoded strings to bytes.
-#[derive(Debug, PartialEq, Eq, serde::Deserialize)]
+#[derive(Clone, Debug, PartialEq, Eq, serde::Deserialize)]
 pub struct HexData(#[serde(with = "hex")] pub Vec<u8>);

zebra-rpc/src/methods/get_block_template_rpcs/types/submit_block.rs

@@ -7,9 +7,23 @@ use crate::methods::get_block_template_rpcs::GetBlockTemplateRpc;
 /// Optional argument `jsonparametersobject` for `submitblock` RPC request
 ///
 /// See notes for [`GetBlockTemplateRpc::submit_block`] method
-#[derive(Debug, serde::Deserialize)]
+#[derive(Clone, Debug, PartialEq, Eq, serde::Deserialize)]
 pub struct JsonParameters {
-    pub(crate) _work_id: Option<String>,
+    /// The workid for the block template.
+    ///
+    /// > If the server provided a workid, it MUST be included with submissions,
+    /// currently unused.
+    ///
+    /// Rationale:
+    ///
+    /// > If servers allow all mutations, it may be hard to identify which job it is based on.
+    /// > While it may be possible to verify the submission by its content, it is much easier
+    /// > to compare it to the job issued. It is very easy for the miner to keep track of this.
+    /// > Therefore, using a "workid" is a very cheap solution to enable more mutations.
+    ///
+    /// <https://en.bitcoin.it/wiki/BIP_0022#Rationale>
+    #[serde(rename = "workid")]
+    pub _work_id: Option<String>,
 }
 
 /// Response to a `submitblock` RPC request.

zebra-rpc/src/methods/tests/snapshot/get_block_template_rpcs.rs

@@ -163,7 +163,7 @@ pub async fn test_responses<State, ReadState>(
             })));
     });
 
-    let get_block_template = tokio::spawn(get_block_template_rpc.get_block_template());
+    let get_block_template = tokio::spawn(get_block_template_rpc.get_block_template(None));
 
     mempool
         .expect_request(mempool::Request::FullTransactions)

zebra-rpc/src/methods/tests/vectors.rs

@@ -865,7 +865,7 @@ async fn rpc_getblocktemplate() {
             })));
     });
 
-    let get_block_template = tokio::spawn(get_block_template_rpc.get_block_template());
+    let get_block_template = tokio::spawn(get_block_template_rpc.get_block_template(None));
 
     mempool
         .expect_request(mempool::Request::FullTransactions)
@@ -921,7 +921,7 @@ async fn rpc_getblocktemplate() {
 
     mock_chain_tip_sender.send_estimated_distance_to_network_chain_tip(Some(200));
     let get_block_template_sync_error = get_block_template_rpc
-        .get_block_template()
+        .get_block_template(None)
         .await
         .expect_err("needs an error when estimated distance to network chain tip is far");
 
@@ -934,7 +934,7 @@ async fn rpc_getblocktemplate() {
 
     mock_chain_tip_sender.send_estimated_distance_to_network_chain_tip(Some(0));
     let get_block_template_sync_error = get_block_template_rpc
-        .get_block_template()
+        .get_block_template(None)
         .await
         .expect_err("needs an error when syncer is not close to tip");
 
@@ -945,7 +945,7 @@ async fn rpc_getblocktemplate() {
 
     mock_chain_tip_sender.send_estimated_distance_to_network_chain_tip(Some(200));
     let get_block_template_sync_error = get_block_template_rpc
-        .get_block_template()
+        .get_block_template(None)
         .await
         .expect_err("needs an error when syncer is not close to tip or estimated distance to network chain tip is far");
 
@@ -953,6 +953,39 @@ async fn rpc_getblocktemplate() {
         get_block_template_sync_error.code,
         ErrorCode::ServerError(-10)
     );
+    let get_block_template_sync_error = get_block_template_rpc
+        .get_block_template(Some(get_block_template_rpcs::types::get_block_template_opts::JsonParameters {
+            mode: get_block_template_rpcs::types::get_block_template_opts::GetBlockTemplateRequestMode::Proposal,
+            ..Default::default()
+        }))
+        .await
+        .expect_err("needs an error when using unsupported mode");
+
+    assert_eq!(get_block_template_sync_error.code, ErrorCode::InvalidParams);
+
+    let get_block_template_sync_error = get_block_template_rpc
+        .get_block_template(Some(
+            get_block_template_rpcs::types::get_block_template_opts::JsonParameters {
+                data: Some(get_block_template_rpcs::types::hex_data::HexData("".into())),
+                ..Default::default()
+            },
+        ))
+        .await
+        .expect_err("needs an error when passing in block data");
+
+    assert_eq!(get_block_template_sync_error.code, ErrorCode::InvalidParams);
+
+    let get_block_template_sync_error = get_block_template_rpc
+        .get_block_template(Some(
+            get_block_template_rpcs::types::get_block_template_opts::JsonParameters {
+                longpollid: Some("".to_string()),
+                ..Default::default()
+            },
+        ))
+        .await
+        .expect_err("needs an error when using unsupported option");
+
+    assert_eq!(get_block_template_sync_error.code, ErrorCode::InvalidParams);
 }
 
 #[cfg(feature = "getblocktemplate-rpcs")]

zebrad/tests/common/get_block_template_rpcs/get_block_template.rs

@@ -63,7 +63,11 @@ pub(crate) async fn run() -> Result<()> {
          with a mempool that is likely empty...",
     );
     let getblocktemplate_response = RPCRequestClient::new(rpc_address)
-        .call("getblocktemplate", "[]".to_string())
+        .call(
+            "getblocktemplate",
+            // test that unknown capabilities are parsed as valid input
+            "[{\"capabilities\": [\"generation\"]}]".to_string(),
+        )
         .await?;
 
     let is_response_success = getblocktemplate_response.status().is_success();