implement debug_setHead

nimbus/db/db_chain.nim

@@ -180,6 +180,13 @@ proc setAsCanonicalChainHead(self: BaseChainDB; headerHash: Hash256): seq[BlockH
 
   return newCanonicalHeaders
 
+proc setHead*(self: BaseChainDB, header: BlockHeader, writeHeader = false) =
+  var headerHash = rlpHash(header)
+  if writeHeader:
+    self.db.put(genericHashKey(headerHash).toOpenArray, rlp.encode(header))
+  self.addBlockNumberToHashLookup(header)
+  self.db.put(canonicalHeadHashKey().toOpenArray, rlp.encode(headerHash))
+
 proc headerExists*(self: BaseChainDB; blockHash: Hash256): bool =
   ## Returns True if the header with the given block hash is in our DB.
   self.db.contains(genericHashKey(blockHash).toOpenArray)

nimbus/rpc/debug.nim

@@ -113,3 +113,11 @@ proc setupDebugRpc*(chainDB: BaseChainDB, rpcsrv: RpcServer) =
       flags = traceOptionsToFlags(options)
 
     traceBlock(chainDB, header, body, flags)
+
+  rpcsrv.rpc("debug_setHead") do(quantityTag: string):
+    ## Sets the current head of the local chain by block number.
+    ## Note, this is a destructive action and may severely damage your chain.
+    ## Use with extreme caution.
+    let
+      header = chainDB.headerFromTag(quantityTag)
+    chainDB.setHead(header)

tests/persistBlockTestGen.nim

@@ -4,12 +4,6 @@ import
   ../nimbus/[tracer, vm_types, config],
   ../nimbus/p2p/chain
 
-proc putCanonicalHead(chainDB: BaseChainDB, header: BlockHeader) =
-  var headerHash = rlpHash(header)
-  chainDB.db.put(genericHashKey(headerHash).toOpenArray, rlp.encode(header))
-  chainDB.addBlockNumberToHashLookup(header)
-  chainDB.db.put(canonicalHeadHashKey().toOpenArray, rlp.encode(headerHash))
-
 proc dumpTest(chainDB: BaseChainDB, blockNumber: int) =
   let
     blockNumber = blockNumber.u256
@@ -30,7 +24,7 @@ proc dumpTest(chainDB: BaseChainDB, blockNumber: int) =
     headers = @[header]
     bodies = @[blockBody]
 
-  captureChainDB.putCanonicalHead(parent)
+  captureChainDB.setHead(parent, true)
   discard chain.persistBlocks(headers, bodies)
 
   var metaData = %{

tests/test_persistblock_json.nim

@@ -16,12 +16,6 @@ proc testFixture(node: JsonNode, testStatusIMPL: var TestStatus)
 suite "persist block json tests":
   jsonTest("PersistBlockTests", testFixture)
 
-proc putCanonicalHead(chainDB: BaseChainDB, header: BlockHeader) =
-  var headerHash = rlpHash(header)
-  chainDB.db.put(genericHashKey(headerHash).toOpenArray, rlp.encode(header))
-  chainDB.addBlockNumberToHashLookup(header)
-  chainDB.db.put(canonicalHeadHashKey().toOpenArray, rlp.encode(headerHash))
-
 # use tracerTestGen.nim to generate additional test data
 proc testFixture(node: JsonNode, testStatusIMPL: var TestStatus) =
   var
@@ -45,6 +39,6 @@ proc testFixture(node: JsonNode, testStatusIMPL: var TestStatus) =
     headers = @[header]
     bodies = @[blockBody]
 
-  chainDB.putCanonicalHead(parent)
+  chainDB.setHead(parent, true)
   let validationResult = chain.persistBlocks(headers, bodies)
   check validationResult == ValidationResult.OK