aboutsummaryrefslogtreecommitdiffstats
path: root/p2p/simulations/adapters/inproc.go
blob: 48d7c1730159cd3247293e9e7e26908b47077f6e (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
// 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

import (
    "errors"
    "fmt"
    "math"
    "net"
    "sync"

    "github.com/ethereum/go-ethereum/event"
    "github.com/ethereum/go-ethereum/log"
    "github.com/ethereum/go-ethereum/node"
    "github.com/ethereum/go-ethereum/p2p"
    "github.com/ethereum/go-ethereum/p2p/discover"
    "github.com/ethereum/go-ethereum/rpc"
)

// SimAdapter is a NodeAdapter which creates in-memory simulation nodes and
// connects them using in-memory net.Pipe connections
type SimAdapter struct {
    mtx      sync.RWMutex
    nodes    map[discover.NodeID]*SimNode
    services map[string]ServiceFunc
}

// NewSimAdapter creates a SimAdapter which is capable of running in-memory
// simulation nodes running any of the given services (the services to run on a
// particular node are passed to the NewNode function in the NodeConfig)
func NewSimAdapter(services map[string]ServiceFunc) *SimAdapter {
    return &SimAdapter{
        nodes:    make(map[discover.NodeID]*SimNode),
        services: services,
    }
}

// Name returns the name of the adapter for logging purposes
func (s *SimAdapter) Name() string {
    return "sim-adapter"
}

// NewNode returns a new SimNode using the given config
func (s *SimAdapter) NewNode(config *NodeConfig) (Node, error) {
    s.mtx.Lock()
    defer s.mtx.Unlock()

    // check a node with the ID doesn't already exist
    id := config.ID
    if _, exists := s.nodes[id]; exists {
        return nil, fmt.Errorf("node already exists: %s", id)
    }

    // check the services are valid
    if len(config.Services) == 0 {
        return nil, errors.New("node must have at least one service")
    }
    for _, service := range config.Services {
        if _, exists := s.services[service]; !exists {
            return nil, fmt.Errorf("unknown node service %q", service)
        }
    }

    n, err := node.New(&node.Config{
        P2P: p2p.Config{
            PrivateKey:      config.PrivateKey,
            MaxPeers:        math.MaxInt32,
            NoDiscovery:     true,
            Dialer:          s,
            EnableMsgEvents: true,
        },
        NoUSB:  true,
        Logger: log.New("node.id", id.String()),
    })
    if err != nil {
        return nil, err
    }

    simNode := &SimNode{
        ID:      id,
        config:  config,
        node:    n,
        adapter: s,
        running: make(map[string]node.Service),
    }
    s.nodes[id] = simNode
    return simNode, nil
}

// Dial implements the p2p.NodeDialer interface by connecting to the node using
// an in-memory net.Pipe connection
func (s *SimAdapter) Dial(dest *discover.Node) (conn net.Conn, err error) {
    node, ok := s.GetNode(dest.ID)
    if !ok {
        return nil, fmt.Errorf("unknown node: %s", dest.ID)
    }
    srv := node.Server()
    if srv == nil {
        return nil, fmt.Errorf("node not running: %s", dest.ID)
    }
    pipe1, pipe2 := net.Pipe()
    go srv.SetupConn(pipe1, 0, nil)
    return pipe2, nil
}

// DialRPC implements the RPCDialer interface by creating an in-memory RPC
// client of the given node
func (s *SimAdapter) DialRPC(id discover.NodeID) (*rpc.Client, error) {
    node, ok := s.GetNode(id)
    if !ok {
        return nil, fmt.Errorf("unknown node: %s", id)
    }
    handler, err := node.node.RPCHandler()
    if err != nil {
        return nil, err
    }
    return rpc.DialInProc(handler), nil
}

// GetNode returns the node with the given ID if it exists
func (s *SimAdapter) GetNode(id discover.NodeID) (*SimNode, bool) {
    s.mtx.RLock()
    defer s.mtx.RUnlock()
    node, ok := s.nodes[id]
    return node, ok
}

// SimNode is an in-memory simulation node which connects to other nodes using
// an in-memory net.Pipe connection (see SimAdapter.Dial), running devp2p
// protocols directly over that pipe
type SimNode struct {
    lock         sync.RWMutex
    ID           discover.NodeID
    config       *NodeConfig
    adapter      *SimAdapter
    node         *node.Node
    running      map[string]node.Service
    client       *rpc.Client
    registerOnce sync.Once
}

// Addr returns the node's discovery address
func (self *SimNode) Addr() []byte {
    return []byte(self.Node().String())
}

// Node returns a discover.Node representing the SimNode
func (self *SimNode) Node() *discover.Node {
    return discover.NewNode(self.ID, net.IP{127, 0, 0, 1}, 30303, 30303)
}

// Client returns an rpc.Client which can be used to communicate with the
// underlying services (it is set once the node has started)
func (self *SimNode) Client() (*rpc.Client, error) {
    self.lock.RLock()
    defer self.lock.RUnlock()
    if self.client == nil {
        return nil, errors.New("node not started")
    }
    return self.client, nil
}

// ServeRPC serves RPC requests over the given connection by creating an
// in-memory client to the node's RPC server
func (self *SimNode) ServeRPC(conn net.Conn) error {
    handler, err := self.node.RPCHandler()
    if err != nil {
        return err
    }
    handler.ServeCodec(rpc.NewJSONCodec(conn), rpc.OptionMethodInvocation|rpc.OptionSubscriptions)
    return nil
}

// Snapshots creates snapshots of the services by calling the
// simulation_snapshot RPC method
func (self *SimNode) Snapshots() (map[string][]byte, error) {
    self.lock.RLock()
    services := make(map[string]node.Service, len(self.running))
    for name, service := range self.running {
        services[name] = service
    }
    self.lock.RUnlock()
    if len(services) == 0 {
        return nil, errors.New("no running services")
    }
    snapshots := make(map[string][]byte)
    for name, service := range services {
        if s, ok := service.(interface {
            Snapshot() ([]byte, error)
        }); ok {
            snap, err := s.Snapshot()
            if err != nil {
                return nil, err
            }
            snapshots[name] = snap
        }
    }
    return snapshots, nil
}

// Start registers the services and starts the underlying devp2p node
func (self *SimNode) Start(snapshots map[string][]byte) error {
    newService := func(name string) func(ctx *node.ServiceContext) (node.Service, error) {
        return func(nodeCtx *node.ServiceContext) (node.Service, error) {
            ctx := &ServiceContext{
                RPCDialer:   self.adapter,
                NodeContext: nodeCtx,
                Config:      self.config,
            }
            if snapshots != nil {
                ctx.Snapshot = snapshots[name]
            }
            serviceFunc := self.adapter.services[name]
            service, err := serviceFunc(ctx)
            if err != nil {
                return nil, err
            }
            self.running[name] = service
            return service, nil
        }
    }

    // ensure we only register the services once in the case of the node
    // being stopped and then started again
    var regErr error
    self.registerOnce.Do(func() {
        for _, name := range self.config.Services {
            if err := self.node.Register(newService(name)); err != nil {
                regErr = err
                return
            }
        }
    })
    if regErr != nil {
        return regErr
    }

    if err := self.node.Start(); err != nil {
        return err
    }

    // create an in-process RPC client
    handler, err := self.node.RPCHandler()
    if err != nil {
        return err
    }

    self.lock.Lock()
    self.client = rpc.DialInProc(handler)
    self.lock.Unlock()

    return nil
}

// Stop closes the RPC client and stops the underlying devp2p node
func (self *SimNode) Stop() error {
    self.lock.Lock()
    if self.client != nil {
        self.client.Close()
        self.client = nil
    }
    self.lock.Unlock()
    return self.node.Stop()
}

// Services returns a copy of the underlying services
func (self *SimNode) Services() []node.Service {
    self.lock.RLock()
    defer self.lock.RUnlock()
    services := make([]node.Service, 0, len(self.running))
    for _, service := range self.running {
        services = append(services, service)
    }
    return services
}

// Server returns the underlying p2p.Server
func (self *SimNode) Server() *p2p.Server {
    return self.node.Server()
}

// SubscribeEvents subscribes the given channel to peer events from the
// underlying p2p.Server
func (self *SimNode) SubscribeEvents(ch chan *p2p.PeerEvent) event.Subscription {
    srv := self.Server()
    if srv == nil {
        panic("node not running")
    }
    return srv.SubscribeEvents(ch)
}

// NodeInfo returns information about the node
func (self *SimNode) NodeInfo() *p2p.NodeInfo {
    server := self.Server()
    if server == nil {
        return &p2p.NodeInfo{
            ID:    self.ID.String(),
            Enode: self.Node().String(),
        }
    }
    return server.NodeInfo()
}