aboutsummaryrefslogtreecommitdiffstats
path: root/app/scripts/controllers/transactions/nonce-tracker.js
blob: 490118c893831c70078b8e9db1830d9e4b3ac043 (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
const EthQuery = require('ethjs-query')
const assert = require('assert')
const Mutex = require('await-semaphore').Mutex
/**
  @param opts {Object}
    @param {Object} opts.provider a ethereum provider
    @param {Function} opts.getPendingTransactions a function that returns an array of txMeta
    whosee status is `submitted`
    @param {Function} opts.getConfirmedTransactions a function that returns an array of txMeta
    whose status is `confirmed`
  @class
*/
class NonceTracker {

  constructor ({ provider, blockTracker, getPendingTransactions, getConfirmedTransactions }) {
    this.provider = provider
    this.blockTracker = blockTracker
    this.ethQuery = new EthQuery(provider)
    this.getPendingTransactions = getPendingTransactions
    this.getConfirmedTransactions = getConfirmedTransactions
    this.lockMap = {}
  }

  /**
    @returns {Promise<Object>} with the key releaseLock (the gloabl mutex)
  */
  async getGlobalLock () {
    const globalMutex = this._lookupMutex('global')
    // await global mutex free
    const releaseLock = await globalMutex.acquire()
    return { releaseLock }
  }

  /**
   * @typedef NonceDetails
   * @property {number} highestLocallyConfirmed - A hex string of the highest nonce on a confirmed transaction.
   * @property {number} nextNetworkNonce - The next nonce suggested by the eth_getTransactionCount method.
   * @property {number} highetSuggested - The maximum between the other two, the number returned.
   */

  /**
  this will return an object with the `nextNonce` `nonceDetails` of type NonceDetails, and the releaseLock
  Note: releaseLock must be called after adding a signed tx to pending transactions (or discarding).

  @param address {string} the hex string for the address whose nonce we are calculating
  @returns {Promise<NonceDetails>}
  */
  async getNonceLock (address) {
    // await global mutex free
    await this._globalMutexFree()
    // await lock free, then take lock
    const releaseLock = await this._takeMutex(address)
    // evaluate multiple nextNonce strategies
    const nonceDetails = {}
    const networkNonceResult = await this._getNetworkNextNonce(address)
    const highestLocallyConfirmed = this._getHighestLocallyConfirmed(address)
    const nextNetworkNonce = networkNonceResult.nonce
    const highestSuggested = Math.max(nextNetworkNonce, highestLocallyConfirmed)

    const pendingTxs = this.getPendingTransactions(address)
    const localNonceResult = this._getHighestContinuousFrom(pendingTxs, highestSuggested) || 0

    nonceDetails.params = {
      highestLocallyConfirmed,
      highestSuggested,
      nextNetworkNonce,
    }
    nonceDetails.local = localNonceResult
    nonceDetails.network = networkNonceResult

    const nextNonce = Math.max(networkNonceResult.nonce, localNonceResult.nonce)
    assert(Number.isInteger(nextNonce), `nonce-tracker - nextNonce is not an integer - got: (${typeof nextNonce}) "${nextNonce}"`)

    // return nonce and release cb
    return { nextNonce, nonceDetails, releaseLock }
  }

  async _getCurrentBlock () {
    const currentBlock = this.blockTracker.getCurrentBlock()
    if (currentBlock) return currentBlock
    return await new Promise((reject, resolve) => {
      this.blockTracker.once('latest', resolve)
    })
  }

  async _globalMutexFree () {
    const globalMutex = this._lookupMutex('global')
    const release = await globalMutex.acquire()
    release()
  }

  async _takeMutex (lockId) {
    const mutex = this._lookupMutex(lockId)
    const releaseLock = await mutex.acquire()
    return releaseLock
  }

  _lookupMutex (lockId) {
    let mutex = this.lockMap[lockId]
    if (!mutex) {
      mutex = new Mutex()
      this.lockMap[lockId] = mutex
    }
    return mutex
  }

  async _getNetworkNextNonce (address) {
    // calculate next nonce
    // we need to make sure our base count
    // and pending count are from the same block
    const currentBlock = await this._getCurrentBlock()
    const blockNumber = currentBlock.blockNumber
    const baseCountBN = await this.ethQuery.getTransactionCount(address, blockNumber || 'latest')
    const baseCount = baseCountBN.toNumber()
    assert(Number.isInteger(baseCount), `nonce-tracker - baseCount is not an integer - got: (${typeof baseCount}) "${baseCount}"`)
    const nonceDetails = { blockNumber, baseCount }
    return { name: 'network', nonce: baseCount, details: nonceDetails }
  }

  _getHighestLocallyConfirmed (address) {
    const confirmedTransactions = this.getConfirmedTransactions(address)
    const highest = this._getHighestNonce(confirmedTransactions)
    return Number.isInteger(highest) ? highest + 1 : 0
  }

  _reduceTxListToUniqueNonces (txList) {
    const reducedTxList = txList.reduce((reducedList, txMeta, index) => {
      if (!index) return [txMeta]
      const nonceMatches = txList.filter((txData) => {
        return txMeta.txParams.nonce === txData.txParams.nonce
      })
      if (nonceMatches.length > 1) return reducedList
      reducedList.push(txMeta)
      return reducedList
    }, [])
    return reducedTxList
  }

  _getHighestNonce (txList) {
    const nonces = txList.map((txMeta) => {
      const nonce = txMeta.txParams.nonce
      assert(typeof nonce, 'string', 'nonces should be hex strings')
      return parseInt(nonce, 16)
    })
    const highestNonce = Math.max.apply(null, nonces)
    return highestNonce
  }

  /**
    @typedef {object} highestContinuousFrom
    @property {string} - name the name for how the nonce was calculated based on the data used
    @property {number} - nonce the next suggested nonce
    @property {object} - details the provided starting nonce that was used (for debugging)
  */
  /**
    @param txList {array} - list of txMeta's
    @param startPoint {number} - the highest known locally confirmed nonce
    @returns {highestContinuousFrom}
  */
  _getHighestContinuousFrom (txList, startPoint) {
    const nonces = txList.map((txMeta) => {
      const nonce = txMeta.txParams.nonce
      assert(typeof nonce, 'string', 'nonces should be hex strings')
      return parseInt(nonce, 16)
    })

    let highest = startPoint
    while (nonces.includes(highest)) {
      highest++
    }

    return { name: 'local', nonce: highest, details: { startPoint, highest } }
  }
}

module.exports = NonceTracker