1 files changed, 108 insertions, 0 deletions
diff --git a/p2p/simulations/events.go b/p2p/simulations/events.go
new file mode 100644
index 000000000..f17958c68
--- /dev/null
+++ b/p2p/simulations/events.go
@@ -0,0 +1,108 @@
+// 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 simulations
+
+import (
+	"fmt"
+	"time"
+)
+
+// EventType is the type of event emitted by a simulation network
+type EventType string
+
+const (
+	// EventTypeNode is the type of event emitted when a node is either
+	// created, started or stopped
+	EventTypeNode EventType = "node"
+
+	// EventTypeConn is the type of event emitted when a connection is
+	// is either established or dropped between two nodes
+	EventTypeConn EventType = "conn"
+
+	// EventTypeMsg is the type of event emitted when a p2p message it
+	// sent between two nodes
+	EventTypeMsg EventType = "msg"
+)
+
+// Event is an event emitted by a simulation network
+type Event struct {
+	// Type is the type of the event
+	Type EventType `json:"type"`
+
+	// Time is the time the event happened
+	Time time.Time `json:"time"`
+
+	// Control indicates whether the event is the result of a controlled
+	// action in the network
+	Control bool `json:"control"`
+
+	// Node is set if the type is EventTypeNode
+	Node *Node `json:"node,omitempty"`
+
+	// Conn is set if the type is EventTypeConn
+	Conn *Conn `json:"conn,omitempty"`
+
+	// Msg is set if the type is EventTypeMsg
+	Msg *Msg `json:"msg,omitempty"`
+}
+
+// NewEvent creates a new event for the given object which should be either a
+// Node, Conn or Msg.
+//
+// The object is copied so that the event represents the state of the object
+// when NewEvent is called.
+func NewEvent(v interface{}) *Event {
+	event := &Event{Time: time.Now()}
+	switch v := v.(type) {
+	case *Node:
+		event.Type = EventTypeNode
+		node := *v
+		event.Node = &node
+	case *Conn:
+		event.Type = EventTypeConn
+		conn := *v
+		event.Conn = &conn
+	case *Msg:
+		event.Type = EventTypeMsg
+		msg := *v
+		event.Msg = &msg
+	default:
+		panic(fmt.Sprintf("invalid event type: %T", v))
+	}
+	return event
+}
+
+// ControlEvent creates a new control event
+func ControlEvent(v interface{}) *Event {
+	event := NewEvent(v)
+	event.Control = true
+	return event
+}
+
+// String returns the string representation of the event
+func (e *Event) String() string {
+	switch e.Type {
+	case EventTypeNode:
+		return fmt.Sprintf("<node-event> id: %s up: %t", e.Node.ID().TerminalString(), e.Node.Up)
+	case EventTypeConn:
+		return fmt.Sprintf("<conn-event> nodes: %s->%s up: %t", e.Conn.One.TerminalString(), e.Conn.Other.TerminalString(), e.Conn.Up)
+	case EventTypeMsg:
+		return fmt.Sprintf("<msg-event> nodes: %s->%s proto: %s, code: %d, received: %t", e.Msg.One.TerminalString(), e.Msg.Other.TerminalString(), e.Msg.Protocol, e.Msg.Code, e.Msg.Received)
+	default:
+		return ""
+	}
+}