db: use kvstore from nim-eth

.gitmodules

@@ -98,11 +98,6 @@
   url = https://github.com/status-im/nim-libp2p.git
   ignore = dirty
   branch = master
-[submodule "vendor/nim-result"]
-  path = vendor/nim-result
-  url = https://github.com/arnetheduck/nim-result.git
-  ignore = dirty
-  branch = master
 [submodule "vendor/nim-nat-traversal"]
   path = vendor/nim-nat-traversal
   url = https://github.com/status-im/nim-nat-traversal.git
@@ -168,3 +163,6 @@
 	url = https://github.com/status-im/nim-testutils.git
 	ignore = dirty
 	branch = master
+[submodule "vendor/nim-sqlite3-abi"]
+	path = vendor/nim-sqlite3-abi
+	url = https://github.com/arnetheduck/nim-sqlite3-abi.git

nimbus/db/select_backend.nim

@@ -1,4 +1,10 @@
-import strutils
+import strutils, eth/db/kvstore
+
+export kvstore
+
+# Database access layer that turns errors in the database into Defects as the
+# code that uses it isn't equipped to handle errors of that kind - this should
+# be reconsidered when making more changes here.
 
 type DbBackend = enum
   sqlite,
@@ -9,11 +15,44 @@ const
   nimbus_db_backend* {.strdefine.} = "rocksdb"
   dbBackend = parseEnum[DbBackend](nimbus_db_backend)
 
+type
+  ChainDB* = ref object of RootObj
+    kv: KvStoreRef
+
+# TODO KvStore is a virtual interface and TrieDB is a virtual interface - one
+#      will be enough eventually - unless the TrieDB interface gains operations
+#      that are not typical to KvStores
+proc get*(db: ChainDB, key: openArray[byte]): seq[byte] =
+  var res: seq[byte]
+  proc onData(data: openArray[byte]) = res = @data
+  if db.kv.get(key, onData).expect("working database"):
+    return res
+
+proc put*(db: ChainDB, key, value: openArray[byte]) =
+  db.kv.put(key, value).expect("working database")
+
+proc contains*(db: ChainDB, key: openArray[byte]): bool =
+  db.kv.contains(key).expect("working database")
+
+proc del*(db: ChainDB, key: openArray[byte]) =
+  db.kv.del(key).expect("working database")
+
 when dbBackend == sqlite:
-  import eth/trie/backends/sqlite_backend as database_backend
+  import eth/db/kvstore_sqlite as database_backend
+  proc newChainDB*(path: string): ChainDB =
+    ChainDB(kv: kvStore SqKvStore.init(path, "nimbus").tryGet())
 elif dbBackend == rocksdb:
-  import eth/trie/backends/rocksdb_backend as database_backend
+  import eth/db/kvstore_rocksdb as database_backend
+  proc newChainDB*(path: string): ChainDB =
+    ChainDB(kv: kvStore RocksStoreRef.init(path, "nimbus").tryGet())
 elif dbBackend == lmdb:
-  import eth/trie/backends/lmdb_backend as database_backend
+  # TODO This implementation has several issues on restricted platforms, possibly
+  #      due to mmap restrictions - see:
+  #      https://github.com/status-im/nim-beacon-chain/issues/732
+  #      https://github.com/status-im/nim-beacon-chain/issues/688
+  # It also has other issues, including exception safety:
+  #      https://github.com/status-im/nim-beacon-chain/pull/809
+
+  {.error: "lmdb deprecated, needs reimplementing".}
 
 export database_backend

vendor/nim-chronicles

@@ -1 +1 @@
-Subproject commit 114cdccaa087c54abcc4dad9ed3366af247de79e
+Subproject commit 3e7f422f11754732df673ed280389024e1ed3cb1

vendor/nim-eth

@@ -1 +1 @@
-Subproject commit 5bb6ee64512cd8db1c52d10145e548860aa938e7
+Subproject commit fab4f9bb1e830cc742105d4c80fd7917ed10717f

vendor/nim-result

@@ -1 +0,0 @@
-Subproject commit bdc585bf9f3ad0acaad18c7d12deab172373b5f4

vendor/nim-rocksdb

@@ -1 +1 @@
-Subproject commit 8da2f119514d933f24efc009182cdea24a5fe107
+Subproject commit e528ee949a753c7c6644da26a4a83197e55a9e35

vendor/nim-sqlite3-abi

@@ -0,0 +1 @@
+Subproject commit fc2028746d367e259d55ba41fdf5587a0683ee59

vendor/nim-stew

@@ -1 +1 @@
-Subproject commit 2a1df5d2dd4963369f2dbae583ab714a1601a8cd
+Subproject commit 8065e36c5af31f2f3f3b0d9ea242ae4eef193a30