client invalidateheader and resetchainhead (#3618)

* wip - "reset_head" via owner api functionality

* jsonrpc pass hash in as a string

* sort of works

* not a reorg if we simply accept several blocks at once

* remember to reset header MMR separately
as it is readonly when interacting with txhashset extension

* basic client integration
needs error handling etc.

* reset sync status when reset chain head

* track "denylist" (todo) and validate headers against this via the ctx

* track denylist (header hashes) in chain itself

* header denylist in play

* expose invalidateheader as client cmd

* rework reset_chain_head - rewind txhashset then header MMR

api/src/handlers/chain_api.rs

@@ -14,7 +14,7 @@
 
 use super::utils::{get_output, get_output_v2, w};
 use crate::chain;
-use crate::core::core::hash::Hashed;
+use crate::core::core::hash::{Hash, Hashed};
 use crate::rest::*;
 use crate::router::{Handler, ResponseFuture};
 use crate::types::*;
@@ -72,6 +72,29 @@ impl Handler for ChainValidationHandler {
 	}
 }
 
+pub struct ChainResetHandler {
+	pub chain: Weak<chain::Chain>,
+	pub sync_state: Weak<chain::SyncState>,
+}
+
+impl ChainResetHandler {
+	pub fn reset_chain_head(&self, hash: Hash) -> Result<(), Error> {
+		let chain = w(&self.chain)?;
+		let header = chain.get_block_header(&hash)?;
+		chain.reset_chain_head(&header)?;
+
+		// Reset the sync status and clear out any sync error.
+		w(&self.sync_state)?.reset();
+		Ok(())
+	}
+
+	pub fn invalidate_header(&self, hash: Hash) -> Result<(), Error> {
+		let chain = w(&self.chain)?;
+		chain.invalidate_header(hash)?;
+		Ok(())
+	}
+}
+
 /// Chain compaction handler. Trigger a compaction of the chain state to regain
 /// storage space.
 /// POST /v1/chain/compact
@@ -81,9 +104,9 @@ pub struct ChainCompactHandler {
 
 impl ChainCompactHandler {
 	pub fn compact_chain(&self) -> Result<(), Error> {
-		w(&self.chain)?
-			.compact()
-			.map_err(|_| ErrorKind::Internal("chain error".to_owned()).into())
+		let chain = w(&self.chain)?;
+		chain.compact()?;
+		Ok(())
 	}
 }
 

api/src/owner.rs

@@ -15,7 +15,8 @@
 //! Owner API External Definition
 
 use crate::chain::{Chain, SyncState};
-use crate::handlers::chain_api::{ChainCompactHandler, ChainValidationHandler};
+use crate::core::core::hash::Hash;
+use crate::handlers::chain_api::{ChainCompactHandler, ChainResetHandler, ChainValidationHandler};
 use crate::handlers::peers_api::{PeerHandler, PeersConnectedHandler};
 use crate::handlers::server_api::StatusHandler;
 use crate::p2p::types::PeerInfoDisplay;
@@ -107,6 +108,26 @@ impl Owner {
 		chain_compact_handler.compact_chain()
 	}
 
+	pub fn reset_chain_head(&self, hash: String) -> Result<(), Error> {
+		let hash = Hash::from_hex(&hash)
+			.map_err(|_| ErrorKind::RequestError("invalid header hash".into()))?;
+		let handler = ChainResetHandler {
+			chain: self.chain.clone(),
+			sync_state: self.sync_state.clone(),
+		};
+		handler.reset_chain_head(hash)
+	}
+
+	pub fn invalidate_header(&self, hash: String) -> Result<(), Error> {
+		let hash = Hash::from_hex(&hash)
+			.map_err(|_| ErrorKind::RequestError("invalid header hash".into()))?;
+		let handler = ChainResetHandler {
+			chain: self.chain.clone(),
+			sync_state: self.sync_state.clone(),
+		};
+		handler.invalidate_header(hash)
+	}
+
 	/// Retrieves information about stored peers.
 	/// If `None` is provided, will list all stored peers.
 	///

api/src/owner_rpc.rs

@@ -132,6 +132,10 @@ pub trait OwnerRpc: Sync + Send {
 	 */
 	fn compact_chain(&self) -> Result<(), ErrorKind>;
 
+	fn reset_chain_head(&self, hash: String) -> Result<(), ErrorKind>;
+
+	fn invalidate_header(&self, hash: String) -> Result<(), ErrorKind>;
+
 	/**
 	Networked version of [Owner::get_peers](struct.Owner.html#method.get_peers).
 
@@ -363,6 +367,14 @@ impl OwnerRpc for Owner {
 		Owner::validate_chain(self).map_err(|e| e.kind().clone())
 	}
 
+	fn reset_chain_head(&self, hash: String) -> Result<(), ErrorKind> {
+		Owner::reset_chain_head(self, hash).map_err(|e| e.kind().clone())
+	}
+
+	fn invalidate_header(&self, hash: String) -> Result<(), ErrorKind> {
+		Owner::invalidate_header(self, hash).map_err(|e| e.kind().clone())
+	}
+
 	fn compact_chain(&self) -> Result<(), ErrorKind> {
 		Owner::compact_chain(self).map_err(|e| e.kind().clone())
 	}
@@ -391,7 +403,7 @@ macro_rules! doctest_helper_json_rpc_owner_assert_response {
 		// create temporary grin server, run jsonrpc request on node api, delete server, return
 		// json response.
 
-		{
+			{
 			/*use grin_servers::test_framework::framework::run_doctest;
 			use grin_util as util;
 			use serde_json;
@@ -425,6 +437,6 @@ macro_rules! doctest_helper_json_rpc_owner_assert_response {
 					serde_json::to_string_pretty(&expected_response).unwrap()
 				);
 				}*/
-		}
+			}
 	};
 }