linter

.eslintrc.json

@@ -21,23 +21,12 @@
         "SwitchCase": 1
       }
     ],
-    "linebreak-style": [
+    "linebreak-style": ["error", "unix"],
-      "error",
+    "quotes": ["error", "single"],
-      "unix"
+    "semi": ["error", "never"],
-    ],
+    "object-curly-spacing": ["error", "always"],
-    "quotes": [
-      "error",
-      "single"
-    ],
-    "semi": [
-      "error",
-      "never"
-    ],
-    "object-curly-spacing": [
-      "error",
-      "always"
-    ],
     "require-await": "error",
+    "comma-dangle": ["error", "never"],
     "space-before-function-paren": [
       "error",
       {

.prettierrc

@@ -0,0 +1,7 @@
+{
+  "semi": false,
+  "arrowParens": "always",
+  "singleQuote": true,
+  "printWidth": 110,
+  "trailingComma": "none"
+}

README.md

@@ -1,18 +1,21 @@
 # Relayer for Tornado Cash [![Build Status](https://travis-ci.org/tornadocash/relayer.svg?branch=master)](https://travis-ci.org/tornadocash/relayer) [![Docker Cloud Build Status](https://img.shields.io/docker/cloud/build/tornadocash/relayer.svg)](https://hub.docker.com/r/tornadocash/relayer/builds)
 
 ## Run locally
+
 1. `npm i`
 2. `cp .env.example .env`
 3. Modify `.env` as needed
 4. `npm run start`
 5. Go to `http://127.0.0.1:8000`
 6. In order to execute withdraw request, you can run following command
+
 ```bash
 curl -X POST -H 'content-type:application/json' --data '<input data>' http://127.0.0.1:8000/relay
 ```
+
 Relayer should return a transaction hash.
 
-*Note.* If you want to change contracts' addresses go to [config.js](./config.js) file.
+_Note._ If you want to change contracts' addresses go to [config.js](./config.js) file.
 
 ## Deploy with docker-compose
 
@@ -20,11 +23,11 @@ docker-compose.yml contains a stack that will automatically provision SSL certif
 
 1. Download docker-compose.yml
 2. Change environment variables for `kovan` containers as appropriate
-    * add `PRIVATE_KEY` for your relayer address (without 0x prefix)
+   - add `PRIVATE_KEY` for your relayer address (without 0x prefix)
-    * set `VIRTUAL_HOST` and `LETSENCRYPT_HOST` to your domain and add DNS record pointing to your relayer ip address
+   - set `VIRTUAL_HOST` and `LETSENCRYPT_HOST` to your domain and add DNS record pointing to your relayer ip address
-    * customize `RELAYER_FEE`
+   - customize `RELAYER_FEE`
-    * update `RPC_URL` if needed
+   - update `RPC_URL` if needed
-    * update `REDIS_URL` if needed
+   - update `REDIS_URL` if needed
 3. Run `docker-compose up -d`
 
 ## Run as a Docker container
@@ -37,22 +40,22 @@ In that case you will need to add https termination yourself because browsers wi
 tornado.cash UI from submitting your request over http connection
 
 ## Input data example
+
 ```json
 {
-    "proof": "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",
+  "proof": "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",
-    "args": [
+  "args": [
-        "0x1579d41e5290ab5bcec9a7df16705e49b5c0b869095299196c19c5e14462c9e3",
+    "0x1579d41e5290ab5bcec9a7df16705e49b5c0b869095299196c19c5e14462c9e3",
-        "0x0cf7f49c5b35c48b9e1d43713e0b46a75977e3d10521e9ac1e4c3cd5e3da1c5d",
+    "0x0cf7f49c5b35c48b9e1d43713e0b46a75977e3d10521e9ac1e4c3cd5e3da1c5d",
-        "0x03ebd0748aa4d1457cf479cce56309641e0a98f5",
+    "0x03ebd0748aa4d1457cf479cce56309641e0a98f5",
-        "0xbd4369dc854c5d5b79fe25492e3a3cfcb5d02da5",
+    "0xbd4369dc854c5d5b79fe25492e3a3cfcb5d02da5",
-        "0x000000000000000000000000000000000000000000000000058d15e176280000",
+    "0x000000000000000000000000000000000000000000000000058d15e176280000",
-        "0x0000000000000000000000000000000000000000000000000000000000000000"
+    "0x0000000000000000000000000000000000000000000000000000000000000000"
-    ],
+  ],
-    "contract": "0xA27E34Ad97F171846bAf21399c370c9CE6129e0D"
+  "contract": "0xA27E34Ad97F171846bAf21399c370c9CE6129e0D"
 }
 ```
 
-
 Disclaimer:
 
 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

src/Fetcher.js

@@ -30,9 +30,7 @@ class Fetcher {
   }
   async fetchPrices() {
     try {
-      let prices = await this.oracle.methods
+      let prices = await this.oracle.methods.getPricesInETH(this.tokenAddresses, this.oneUintAmount).call()
-        .getPricesInETH(this.tokenAddresses, this.oneUintAmount)
-        .call()
       this.ethPrices = prices.reduce((acc, price, i) => {
         acc[this.currencyLookup[this.tokenAddresses[i]]] = price
         return acc

src/index.js

@@ -34,16 +34,17 @@ app.use(function (req, res, next) {
 
 app.get('/', function (req, res) {
   // just for testing purposes
-  res.send('This is <a href=https://tornado.cash>tornado.cash</a> Relayer service. Check the <a href=/status>/status</a> for settings')
+  res.send(
+    'This is <a href=https://tornado.cash>tornado.cash</a> Relayer service. Check the <a href=/status>/status</a> for settings'
+  )
 })
 
-
 app.get('/status', async function (req, res) {
   let nonce = await redisClient.get('nonce')
   let latestBlock = null
   try {
     latestBlock = await web3.eth.getBlockNumber()
-  } catch(e) {
+  } catch (e) {
     console.error('Problem with RPC', e)
   }
   const { ethPrices } = fetcher
@@ -74,7 +75,12 @@ console.log(`mixers: ${JSON.stringify(mixers)}`)
 console.log(`netId: ${netId}`)
 console.log(`ethPrices: ${JSON.stringify(fetcher.ethPrices)}`)
 
-const { GAS_PRICE_BUMP_PERCENTAGE, ALLOWABLE_PENDING_TX_TIMEOUT, NONCE_WATCHER_INTERVAL, MAX_GAS_PRICE } = process.env
+const {
+  GAS_PRICE_BUMP_PERCENTAGE,
+  ALLOWABLE_PENDING_TX_TIMEOUT,
+  NONCE_WATCHER_INTERVAL,
+  MAX_GAS_PRICE
+} = process.env
 if (!NONCE_WATCHER_INTERVAL) {
   console.log(`NONCE_WATCHER_INTERVAL is not set. Using default value ${watherInterval / 1000} sec`)
 }

src/relayController.js

@@ -1,9 +1,7 @@
 const Queue = require('bull')
 const { numberToHex, toWei, toHex, toBN, toChecksumAddress } = require('web3-utils')
 const mixerABI = require('../abis/mixerABI.json')
-const {
+const { isValidProof, isValidArgs, isKnownContract, isEnoughFee } = require('./utils')
-  isValidProof, isValidArgs, isKnownContract, isEnoughFee
-} = require('./utils')
 const config = require('../config')
 const { redisClient, redisOpts } = require('./redis')
 
@@ -28,14 +26,15 @@ async function relayController(req, resp) {
     return resp.status(400).json({ error: 'Proof format is invalid' })
   }
 
-  ({ valid, reason } = isValidArgs(args))
+  // eslint-disable-next-line no-extra-semi
+  ;({ valid, reason } = isValidArgs(args))
   if (!valid) {
     console.log('Args are invalid:', reason)
     return resp.status(400).json({ error: 'Withdraw arguments are invalid' })
   }
 
   let currency, amount
-  ({ valid, currency, amount } = isKnownContract(contract))
+  ;({ valid, currency, amount } = isKnownContract(contract))
   if (!valid) {
     console.log('Contract does not exist:', contract)
     return resp.status(400).json({ error: 'This relayer does not support the token' })
@@ -59,9 +58,20 @@ async function relayController(req, resp) {
     return resp.status(400).json({ error: 'Relayer address is invalid' })
   }
 
-  requestJob = await withdrawQueue.add({
+  requestJob = await withdrawQueue.add(
-    contract, nullifierHash, root, proof, args, currency, amount, fee: fee.toString(), refund: refund.toString()
+    {
-  }, { removeOnComplete: true })
+      contract,
+      nullifierHash,
+      root,
+      proof,
+      args,
+      currency,
+      amount,
+      fee: fee.toString(),
+      refund: refund.toString()
+    },
+    { removeOnComplete: true }
+  )
   reponseCbs[requestJob.id] = resp
 }
 
@@ -102,7 +112,15 @@ withdrawQueue.process(async function (job, done) {
 
     gas += 50000
     const ethPrices = fetcher.ethPrices
-    const { isEnough, reason } = isEnoughFee({ gas, gasPrices, currency, amount, refund: toBN(refund), ethPrices, fee: toBN(fee) })
+    const { isEnough, reason } = isEnoughFee({
+      gas,
+      gasPrices,
+      currency,
+      amount,
+      refund: toBN(refund),
+      ethPrices,
+      fee: toBN(fee)
+    })
     if (!isEnough) {
       console.log(`Wrong fee: ${reason}`)
       done(null, {

src/sender.js

@@ -38,38 +38,43 @@ class Sender {
     let signedTx = await this.web3.eth.accounts.signTransaction(tx, config.privateKey)
     let result = this.web3.eth.sendSignedTransaction(signedTx.rawTransaction)
 
-    result.once('transactionHash', (txHash) => {
+    result
-      console.log(`A new successfully sent tx ${txHash}`)
+      .once('transactionHash', (txHash) => {
-      if (done) {
+        console.log(`A new successfully sent tx ${txHash}`)
-        done(null, {
+        if (done) {
-          status: 200,
+          done(null, {
-          msg: { txHash }
+            status: 200,
-        })
+            msg: { txHash }
-      }
+          })
-    }).on('error', async (e) => {
-      console.log(`Error for tx with nonce ${tx.nonce}\n${e.message}`)
-      if (e.message === 'Returned error: Transaction gas price supplied is too low. There is another transaction with same nonce in the queue. Try increasing the gas price or incrementing the nonce.'
-        || e.message === 'Returned error: Transaction nonce is too low. Try incrementing the nonce.'
-        || e.message === 'Returned error: nonce too low'
-        || e.message === 'Returned error: replacement transaction underpriced') {
-        console.log('nonce too low, retrying')
-        if (retryAttempt <= 10) {
-          retryAttempt++
-          const newNonce = tx.nonce + 1
-          tx.nonce = newNonce
-          await redisClient.set('nonce', newNonce)
-          await redisClient.set('tx:' + newNonce, JSON.stringify(tx))
-          this.sendTx(tx, done, retryAttempt)
-          return
         }
-      }
+      })
-      if (done) {
+      .on('error', async (e) => {
-        done(null, {
+        console.log(`Error for tx with nonce ${tx.nonce}\n${e.message}`)
-          status: 400,
+        if (
-          msg: { error: 'Internal Relayer Error. Please use a different relayer service' }
+          e.message ===
-        })
+            'Returned error: Transaction gas price supplied is too low. There is another transaction with same nonce in the queue. Try increasing the gas price or incrementing the nonce.' ||
-      }
+          e.message === 'Returned error: Transaction nonce is too low. Try incrementing the nonce.' ||
-    })
+          e.message === 'Returned error: nonce too low' ||
+          e.message === 'Returned error: replacement transaction underpriced'
+        ) {
+          console.log('nonce too low, retrying')
+          if (retryAttempt <= 10) {
+            retryAttempt++
+            const newNonce = tx.nonce + 1
+            tx.nonce = newNonce
+            await redisClient.set('nonce', newNonce)
+            await redisClient.set('tx:' + newNonce, JSON.stringify(tx))
+            this.sendTx(tx, done, retryAttempt)
+            return
+          }
+        }
+        if (done) {
+          done(null, {
+            status: 400,
+            msg: { error: 'Internal Relayer Error. Please use a different relayer service' }
+          })
+        }
+      })
   }
 }
 

src/setupWeb3.js

@@ -8,7 +8,7 @@ function setup() {
     web3.eth.accounts.wallet.add('0x' + privateKey)
     web3.eth.defaultAccount = account.address
     return web3
-  } catch(e) {
+  } catch (e) {
     console.error('web3 failed')
   }
 }

src/utils.js

@@ -4,7 +4,7 @@ const { netId, mixers, relayerServiceFee } = require('../config')
 function isValidProof(proof) {
   // validator expects `websnarkUtils.toSolidityInput(proof)` output
 
-  if (!(proof)) {
+  if (!proof) {
     return { valid: false, reason: 'The proof is empty.' }
   }
 
@@ -16,8 +16,7 @@ function isValidProof(proof) {
 }
 
 function isValidArgs(args) {
-
+  if (!args) {
-  if (!(args)) {
     return { valid: false, reason: 'Args are empty' }
   }
 
@@ -25,18 +24,20 @@ function isValidArgs(args) {
     return { valid: false, reason: 'Length of args is lower than 6' }
   }
 
-  for(let signal of args) {
+  for (let signal of args) {
     if (!isHexStrict(signal)) {
       return { valid: false, reason: `Corrupted signal ${signal}` }
     }
   }
 
-  if (args[0].length !== 66 ||
+  if (
-      args[1].length !== 66 ||
+    args[0].length !== 66 ||
-      args[2].length !== 42 ||
+    args[1].length !== 66 ||
-      args[3].length !== 42 ||
+    args[2].length !== 42 ||
-      args[4].length !== 66 ||
+    args[3].length !== 42 ||
-      args[5].length !== 66) {
+    args[4].length !== 66 ||
+    args[5].length !== 66
+  ) {
     return { valid: false, reason: 'The length one of the signals is incorrect' }
   }
 
@@ -56,7 +57,7 @@ function isKnownContract(contract) {
 }
 
 function sleep(ms) {
-  return new Promise(resolve => setTimeout(resolve, ms))
+  return new Promise((resolve) => setTimeout(resolve, ms))
 }
 
 function fromDecimals(value, decimals) {
@@ -77,9 +78,7 @@ function fromDecimals(value, decimals) {
   // Split it into a whole and fractional part
   const comps = ether.split('.')
   if (comps.length > 2) {
-    throw new Error(
+    throw new Error('[ethjs-unit] while converting number ' + value + ' to wei,  too many decimal points')
-      '[ethjs-unit] while converting number ' + value + ' to wei,  too many decimal points'
-    )
   }
 
   let whole = comps[0]
@@ -92,9 +91,7 @@ function fromDecimals(value, decimals) {
     fraction = '0'
   }
   if (fraction.length > baseLength) {
-    throw new Error(
+    throw new Error('[ethjs-unit] while converting number ' + value + ' to wei, too many decimal places')
-      '[ethjs-unit] while converting number ' + value + ' to wei, too many decimal places'
-    )
   }
 
   while (fraction.length < baseLength) {
@@ -114,9 +111,15 @@ function fromDecimals(value, decimals) {
 
 function isEnoughFee({ gas, gasPrices, currency, amount, refund, ethPrices, fee }) {
   const { decimals } = mixers[`netId${netId}`][currency]
-  const decimalsPoint = Math.floor(relayerServiceFee) === relayerServiceFee ? 0 : relayerServiceFee.toString().split('.')[1].length
+  const decimalsPoint =
+    Math.floor(relayerServiceFee) === relayerServiceFee
+      ? 0
+      : relayerServiceFee.toString().split('.')[1].length
+
   const roundDecimal = 10 ** decimalsPoint
-  const feePercent = toBN(fromDecimals(amount, decimals)).mul(toBN(relayerServiceFee * roundDecimal)).div(toBN(roundDecimal * 100))
+  const feePercent = toBN(fromDecimals(amount, decimals))
+    .mul(toBN(relayerServiceFee * roundDecimal))
+    .div(toBN(roundDecimal * 100))
   const expense = toBN(toWei(gasPrices.fast.toString(), 'gwei')).mul(toBN(gas))
   let desiredFee
   switch (currency) {
@@ -125,15 +128,20 @@ function isEnoughFee({ gas, gasPrices, currency, amount, refund, ethPrices, fee
       break
     }
     default: {
-      desiredFee = 
+      desiredFee = expense
-        expense.add(refund)
+        .add(refund)
-          .mul(toBN(10 ** decimals))
+        .mul(toBN(10 ** decimals))
-          .div(toBN(ethPrices[currency]))
+        .div(toBN(ethPrices[currency]))
       desiredFee = desiredFee.add(feePercent)
       break
     }
   }
-  console.log('sent fee, desired fee, feePercent', fee.toString(), desiredFee.toString(), feePercent.toString())
+  console.log(
+    'sent fee, desired fee, feePercent',
+    fee.toString(),
+    desiredFee.toString(),
+    feePercent.toString()
+  )
   if (fee.lt(desiredFee)) {
     return { isEnough: false, reason: 'Not enough fee' }
   }
@@ -148,11 +156,7 @@ function getArgsForOracle() {
   Object.entries(tokens).map(([currency, data]) => {
     if (currency !== 'eth') {
       tokenAddresses.push(data.tokenAddress)
-      oneUintAmount.push(
+      oneUintAmount.push(toBN('10').pow(toBN(data.decimals.toString())).toString())
-        toBN('10')
-          .pow(toBN(data.decimals.toString()))
-          .toString()
-      )
       currencyLookup[data.tokenAddress] = currency
     }
   })
@@ -163,4 +167,12 @@ function getMixers() {
   return mixers[`netId${netId}`]
 }
 
-module.exports = { isValidProof, isValidArgs, sleep, isKnownContract, isEnoughFee, getMixers, getArgsForOracle }
+module.exports = {
+  isValidProof,
+  isValidArgs,
+  sleep,
+  isKnownContract,
+  isEnoughFee,
+  getMixers,
+  getArgsForOracle
+}