p2p/simulations: add mocker functionality (#15207)

This commit adds mocker functionality to p2p/simulations. A
mocker allows to starting/stopping of nodes via the HTTP API.

p2p/simulations/adapters/state.go

@@ -0,0 +1,35 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+package adapters
+
+type SimStateStore struct {
+	m map[string][]byte
+}
+
+func (self *SimStateStore) Load(s string) ([]byte, error) {
+	return self.m[s], nil
+}
+
+func (self *SimStateStore) Save(s string, data []byte) error {
+	self.m[s] = data
+	return nil
+}
+
+func NewSimStateStore() *SimStateStore {
+	return &SimStateStore{
+		make(map[string][]byte),
+	}
+}