Slashing protection updates (#2333)

* Fix slashing protection always try to migrate at startup
* Add CLI option for dual DB

beacon_chain/conf.nim

@@ -120,6 +120,13 @@ type
       desc: "Subscribe to all attestation subnet topics when gossiping"
       name: "subscribe-all-subnets" }: bool
 
+    # Can we use a set[enum]?
+    testDualSlashingProtectionDBs* {.
+      hidden
+      defaultValue: false
+      desc: "Use the the 2 slashing protection implementation at the same time to ensure no regression."
+      name: "slashing-test-dual-db" }: bool
+
     case cmd* {.
       command
       defaultValue: noCommand }: BNStartUpCmd
@@ -664,4 +671,3 @@ func defaultAdminListenAddress*(conf: BeaconNodeConf|ValidatorClientConf): Valid
 template writeValue*(writer: var JsonWriter,
                      value: TypedInputFile|InputFile|InputDir|OutPath|OutDir|OutFile) =
   writer.writeValue(string value)
-

beacon_chain/nimbus_beacon_node.nim

@@ -320,6 +320,17 @@ proc init*(T: type BeaconNode,
         topics &= getAttestationTopic(enrForkId.forkDigest, subnet)
       topics)
 
+  if conf.testDualSlashingProtectionDBs:
+    info "Loading slashing protection database (dual DB mode)", path = conf.validatorsDir()
+    res.attachedValidators = ValidatorPool.init(
+      SlashingProtectionDB.init(
+        chainDag.headState.data.data.genesis_validators_root,
+        conf.validatorsDir(), "slashing_protection",
+        modes = {kCompleteArchiveV1, kCompleteArchiveV2},
+        disagreementBehavior = kChooseV2
+      )
+    )
+  else:
     info "Loading slashing protection database", path = conf.validatorsDir()
     res.attachedValidators = ValidatorPool.init(
       SlashingProtectionDB.init(

beacon_chain/validator_protection/slashing_protection.nim

@@ -67,29 +67,6 @@ func version*(_: type SlashingProtectionDB): static int =
   # The highest DB version supported
   2
 
-# DB Migration
-# -------------------------------------------------------------
-
-proc requiresMigrationFromDB_v1(db: SlashingProtectionDB_v2): bool =
-  ## Migrate a v1 DB to v2.
-  # Check if we have v2 data:
-  let rawdb = kvstore db.getRawDBHandle()
-
-  let v1Root = rawdb.getMetadataTable_DbV1()
-  if v1Root.isNone():
-    return false
-
-  let v2Root = db.getMetadataTable_DbV2()
-  if v2Root.isNone():
-    return true
-
-  if v1Root != v2Root:
-    fatal "Trying to merge-migrate slashing databases from different chains",
-      v1Root = shortLog(v1Root.get()),
-      v2Root = shortLog(v2Root.get())
-    quit 1
-  return true
-
 # Resource Management
 # -------------------------------------------------------------
 
@@ -113,12 +90,11 @@ proc init*(
   result.modes = modes
   result.disagreementBehavior = disagreementBehavior
 
-  result.db_v2 = SlashingProtectionDB_v2.initCompatV1(
+  let (db, requiresMigration) = SlashingProtectionDB_v2.initCompatV1(
     genesis_validators_root,
     basePath, dbname
   )
-
-  let requiresMigration = result.db_v2.requiresMigrationFromDB_v1()
+  result.db_v2 = db
 
   let rawdb = kvstore result.db_v2.getRawDBHandle()
   if not rawdb.checkOrPutGenesis_DbV1(genesis_validators_root):
@@ -433,10 +409,4 @@ proc inclSPDIR*(db: SlashingProtectionDB, spdir: SPDIR): SlashingImportStatus
 # Sanity check
 # --------------------------------------------------------------
 
-proc foo(db: SlashingProtectionDB_Concept) =
-  discard
-
-var x: SlashingProtectionDB
-foo(x) {.explain.}
-
 static: doAssert SlashingProtectionDB is SlashingProtectionDB_Concept

beacon_chain/validator_protection/slashing_protection_v2.nim

@@ -594,24 +594,30 @@ proc getMetadataTable_DbV2*(db: SlashingProtectionDB_v2): Option[Eth2Digest] =
 proc initCompatV1*(T: type SlashingProtectionDB_v2,
            genesis_validators_root: Eth2Digest,
            basePath: string,
-           dbname: string): T =
+           dbname: string
+     ): tuple[db: SlashingProtectionDB_v2, requiresMigration: bool] =
   ## Initialize a new slashing protection database
   ## or load an existing one with matching genesis root
   ## `dbname` MUST not be ending with .sqlite3
 
   let alreadyExists = fileExists(basepath/dbname&".sqlite3")
 
-  result = T(backend: SqStoreRef.init(
+  result.db = T(backend: SqStoreRef.init(
       basePath, dbname,
       keyspaces = ["kvstore"] # The key compat part
     ).get())
-  if alreadyExists and result.getMetadataTable_DbV2().isSome():
-    result.checkDB(genesis_validators_root)
+  if alreadyExists and result.db.getMetadataTable_DbV2().isSome():
+    result.db.checkDB(genesis_validators_root)
+    result.requiresMigration = false
+  elif alreadyExists:
+    result.db.setupDB(genesis_validators_root)
+    result.requiresMigration = true
   else:
-    result.setupDB(genesis_validators_root)
+    result.db.setupDB(genesis_validators_root)
+    result.requiresMigration = false
 
   # Cached queries
-  result.setupCachedQueries()
+  result.db.setupCachedQueries()
 
 # Resource Management
 # -------------------------------------------------------------