Merge pull request #495 from opengsn/OG-237-acceptance-budget

OG-237 acceptanceBalance protocol

src/cli/CommandsLogic.ts

@@ -101,7 +101,7 @@ export default class CommandsLogic {
 
   async isRelayReady (relayUrl: string): Promise<boolean> {
     const response = await this.httpClient.getPingResponse(relayUrl)
-    return response.Ready
+    return response.ready
   }
 
   async waitForRelay (relayUrl: string): Promise<void> {
@@ -176,8 +176,8 @@ export default class CommandsLogic {
       console.error(`Funding GSN relay at ${options.relayUrl}`)
 
       const response = await this.httpClient.getPingResponse(options.relayUrl)
-      const relayAddress = response.RelayManagerAddress
-      const relayHubAddress = this.config.relayHubAddress ?? response.RelayHubAddress
+      const relayAddress = response.relayManagerAddress
+      const relayHubAddress = this.config.relayHubAddress ?? response.relayHubAddress
 
       const relayHub = await this.contractInteractor._createRelayHub(relayHubAddress)
       const stakeManagerAddress = await relayHub.stakeManager()

src/cli/commands/gsn-status.ts

@@ -50,7 +50,7 @@ const commander = gsnCommander(['n', 'h'])
       res.push(`\tbalance: ${Web3.utils.fromWei(managerBalance)} ETH`)
     }
     const pingResult = statistics.relayPings.get(registeredEvent.relayUrl)
-    const status = pingResult?.pingResponse != null ? pingResult.pingResponse.Ready.toString() : pingResult?.error?.toString() ?? 'unknown'
+    const status = pingResult?.pingResponse != null ? pingResult.pingResponse.ready.toString() : pingResult?.error?.toString() ?? 'unknown'
     res.push(`\tstatus: ${status}`)
     console.log('- ' + res.join(' '))
   })

src/common/PingResponse.ts

@@ -1,12 +1,13 @@
 import { Address, IntString } from '../relayclient/types/Aliases'
 
 export default interface PingResponse {
-  // TODO: this should be 'worker'
-  RelayServerAddress: Address
-  RelayManagerAddress: Address
-  RelayHubAddress: Address
-  MinGasPrice: IntString
-  MaxAcceptanceBudget: IntString
-  Ready: boolean
-  Version: string
+  relayWorkerAddress: Address
+  relayManagerAddress: Address
+  relayHubAddress: Address
+  minGasPrice: IntString
+  maxAcceptanceBudget: IntString
+  networkId?: IntString
+  chainId?: IntString
+  ready: boolean
+  version: string
 }

src/relayclient/HttpClient.ts

@@ -14,8 +14,9 @@ export default class HttpClient {
     this.config = config
   }
 
-  async getPingResponse (relayUrl: string): Promise<PingResponse> {
-    const pingResponse: PingResponse = await this.httpWrapper.sendPromise(relayUrl + '/getaddr', {})
+  async getPingResponse (relayUrl: string, paymaster?: string): Promise<PingResponse> {
+    const paymasterSuffix = paymaster == null ? '' : '?paymaster=' + paymaster
+    const pingResponse: PingResponse = await this.httpWrapper.sendPromise(relayUrl + '/getaddr' + paymasterSuffix, {})
     if (this.config.verbose) {
       console.log('error, body', pingResponse)
     }

src/relayclient/RelayClient.ts

@@ -35,9 +35,9 @@ export const EmptyDataCallback: AsyncDataCallback = async (): Promise<PrefixedHe
 export const GasPricePingFilter: PingFilter = (pingResponse, gsnTransactionDetails) => {
   if (
     gsnTransactionDetails.gasPrice != null &&
-    parseInt(pingResponse.MinGasPrice) > parseInt(gsnTransactionDetails.gasPrice)
+    parseInt(pingResponse.minGasPrice) > parseInt(gsnTransactionDetails.gasPrice)
   ) {
-    throw new Error(`Proposed gas price: ${gsnTransactionDetails.gasPrice}; relay's MinGasPrice: ${pingResponse.MinGasPrice}`)
+    throw new Error(`Proposed gas price: ${gsnTransactionDetails.gasPrice}; relay's MinGasPrice: ${pingResponse.minGasPrice}`)
   }
 }
 
@@ -218,7 +218,7 @@ export class RelayClient {
     if (this.config.verbose) {
       console.log(`attempting relay: ${JSON.stringify(relayInfo)} transaction: ${JSON.stringify(gsnTransactionDetails)}`)
     }
-    const maxAcceptanceBudget = parseInt(relayInfo.pingResponse.MaxAcceptanceBudget)
+    const maxAcceptanceBudget = parseInt(relayInfo.pingResponse.maxAcceptanceBudget)
     const httpRequest = await this._prepareRelayHttpRequest(relayInfo, gsnTransactionDetails)
 
     this.emit(new GsnValidateRequestEvent())
@@ -267,7 +267,7 @@ export class RelayClient {
     const paymaster = gsnTransactionDetails.paymaster ?? this.config.paymasterAddress
 
     const senderNonce = await this.contractInteractor.getSenderNonce(gsnTransactionDetails.from, forwarderAddress)
-    const relayWorker = relayInfo.pingResponse.RelayServerAddress
+    const relayWorker = relayInfo.pingResponse.relayWorkerAddress
     const gasPriceHex = gsnTransactionDetails.gasPrice
     const gasLimitHex = gsnTransactionDetails.gas
     if (gasPriceHex == null || gasLimitHex == null) {

src/relayclient/RelaySelectionManager.ts

@@ -63,7 +63,7 @@ export default class RelaySelectionManager {
       if (isInfoFromEvent(raceResult.winner.relayInfo)) {
         return (raceResult.winner as RelayInfo)
       } else {
-        const managerAddress = raceResult.winner.pingResponse.RelayManagerAddress
+        const managerAddress = raceResult.winner.pingResponse.relayManagerAddress
         if (this.config.verbose) {
           console.log(`finding relay register info for manager address: ${managerAddress}; known info: ${JSON.stringify(raceResult.winner.relayInfo)}`)
         }
@@ -118,9 +118,9 @@ export default class RelaySelectionManager {
     if (this.config.verbose) {
       console.log(`getRelayAddressPing URL: ${relayInfo.relayUrl}`)
     }
-    const pingResponse = await this.httpClient.getPingResponse(relayInfo.relayUrl)
+    const pingResponse = await this.httpClient.getPingResponse(relayInfo.relayUrl, this.gsnTransactionDetails.paymaster)
 
-    if (!pingResponse.Ready) {
+    if (!pingResponse.ready) {
       throw new Error(`Relay not ready ${JSON.stringify(pingResponse)}`)
     }
     this.pingFilter(pingResponse, this.gsnTransactionDetails)

src/relayserver/HttpServer.ts

@@ -76,9 +76,9 @@ export class HttpServer {
   }
 
   pingHandler (req: any, res: any): void {
-    const pingResponse = this.backend.pingHandler()
+    const pingResponse = this.backend.pingHandler(req.query.paymaster)
     res.send(pingResponse)
-    console.log(`address ${pingResponse.RelayServerAddress} sent. ready: ${pingResponse.Ready}`)
+    console.log(`address ${pingResponse.relayWorkerAddress} sent. ready: ${pingResponse.ready}`)
   }
 
   async relayHandler (req: any, res: any): Promise<void> {

src/relayserver/RelayServer.ts

@@ -25,9 +25,10 @@ import { SendTransactionDetails, TransactionManager } from './TransactionManager
 import { configureServer, ServerConfigParams, ServerDependencies } from './ServerConfigParams'
 import { TxStoreManager } from './TxStoreManager'
 import { ServerAction } from './StoredTransaction'
+import { IntString } from '../relayclient/types/Aliases'
 import Timeout = NodeJS.Timeout
 
-const VERSION = '2.0.0-beta.2'
+const VERSION = '2.0.0-beta.3'
 const GAS_RESERVE = 100000
 
 export class RelayServer extends EventEmitter {
@@ -56,6 +57,8 @@ export class RelayServer extends EventEmitter {
   networkId!: number
   relayHubContract!: IRelayHubInstance
 
+  trustedPaymastersGasLimits: Map<String|undefined, PaymasterGasLimits> = new Map<String|undefined, PaymasterGasLimits>()
+
   constructor (config: Partial<ServerConfigParams>, dependencies: ServerDependencies) {
     super()
     this.versionManager = new VersionsManager(VERSION)
@@ -66,22 +69,24 @@ export class RelayServer extends EventEmitter {
     this.managerAddress = this.transactionManager.managerKeyManager.getAddress(0)
     this.workerAddress = this.transactionManager.workersKeyManager.getAddress(0)
     log.setLevel(this.config.logLevel)
-    log.debug('config:', JSON.stringify(this.config))
+    log.debug('server config:', JSON.stringify(this.config, null, 2))
   }
 
   getMinGasPrice (): number {
     return this.gasPrice
   }
 
-  pingHandler (): PingResponse {
+  pingHandler (paymaster?: string): PingResponse {
     return {
-      RelayServerAddress: this.workerAddress,
-      RelayManagerAddress: this.managerAddress,
-      RelayHubAddress: this.relayHubContract?.address ?? '',
-      MinGasPrice: this.getMinGasPrice().toString(),
-      MaxAcceptanceBudget: this.config.maxAcceptanceBudget.toString(),
-      Ready: this.ready,
-      Version: VERSION
+      relayWorkerAddress: this.workerAddress,
+      relayManagerAddress: this.managerAddress,
+      relayHubAddress: this.relayHubContract?.address ?? '',
+      minGasPrice: this.getMinGasPrice().toString(),
+      maxAcceptanceBudget: this._getPaymasterMaxAcceptanceBudget(paymaster),
+      chainId: this.chainId.toString(),
+      networkId: this.networkId.toString(),
+      ready: this.ready,
+      version: VERSION
     }
   }
 
@@ -135,29 +140,36 @@ export class RelayServer extends EventEmitter {
     maxPossibleGas: number
     acceptanceBudget: number
   }> {
-    let gasLimits: PaymasterGasLimits
-    try {
-      const paymasterContract = await this.contractInteractor._createPaymaster(req.relayRequest.relayData.paymaster)
-      gasLimits = await paymasterContract.getGasLimits()
-    } catch (e) {
-      const error = e as Error
-      let message = `unknown paymaster error: ${error.message}`
-      if (error.message.includes('Returned values aren\'t valid, did it run Out of Gas?')) {
-        message = `incompatible paymaster contract: ${req.relayRequest.relayData.paymaster}`
-      } else if (error.message.includes('no code at address')) {
-        message = `'non-existent paymaster contract: ${req.relayRequest.relayData.paymaster}`
+    const paymaster = req.relayRequest.relayData.paymaster
+    let gasLimits = this.trustedPaymastersGasLimits.get(paymaster)
+    let acceptanceBudget: number
+    if (gasLimits == null) {
+      try {
+        const paymasterContract = await this.contractInteractor._createPaymaster(paymaster)
+        gasLimits = await paymasterContract.getGasLimits()
+      } catch (e) {
+        const error = e as Error
+        let message = `unknown paymaster error: ${error.message}`
+        if (error.message.includes('Returned values aren\'t valid, did it run Out of Gas?')) {
+          message = `incompatible paymaster contract: ${paymaster}`
+        } else if (error.message.includes('no code at address')) {
+          message = `'non-existent paymaster contract: ${paymaster}`
+        }
+        throw new Error(message)
       }
-      throw new Error(message)
-    }
-    let acceptanceBudget = this.config.maxAcceptanceBudget
-    const paymasterAcceptanceBudget = parseInt(gasLimits.acceptanceBudget)
-    if (paymasterAcceptanceBudget > acceptanceBudget) {
-      if (!this._isTrustedPaymaster(req.relayRequest.relayData.paymaster)) {
-        throw new Error(
-          `paymaster acceptance budget too high. given: ${paymasterAcceptanceBudget} max allowed: ${this.config.maxAcceptanceBudget}`)
+      acceptanceBudget = this.config.maxAcceptanceBudget
+      const paymasterAcceptanceBudget = parseInt(gasLimits.acceptanceBudget)
+      if (paymasterAcceptanceBudget > acceptanceBudget) {
+        if (!this._isTrustedPaymaster(paymaster)) {
+          throw new Error(
+              `paymaster acceptance budget too high. given: ${paymasterAcceptanceBudget} max allowed: ${this.config.maxAcceptanceBudget}`)
+        }
+        log.debug(`Using trusted paymaster's higher than max acceptance budget: ${paymasterAcceptanceBudget}`)
+        acceptanceBudget = paymasterAcceptanceBudget
       }
-      log.debug(`Using trusted paymaster's higher than max acceptance budget: ${paymasterAcceptanceBudget}`)
-      acceptanceBudget = paymasterAcceptanceBudget
+    } else {
+      // its a trusted paymaster. just use its acceptance budget as-is
+      acceptanceBudget = parseInt(gasLimits.acceptanceBudget)
     }
 
     const hubOverhead = (await this.relayHubContract.gasOverhead()).toNumber()
@@ -168,7 +180,7 @@ export class RelayServer extends EventEmitter {
     })
     const maxCharge =
       await this.relayHubContract.calculateCharge(maxPossibleGas, req.relayRequest.relayData)
-    const paymasterBalance = await this.relayHubContract.balanceOf(req.relayRequest.relayData.paymaster)
+    const paymasterBalance = await this.relayHubContract.balanceOf(paymaster)
 
     if (paymasterBalance.lt(maxCharge)) {
       throw new Error(`paymaster balance too low: ${paymasterBalance.toString()}, maxCharge: ${maxCharge.toString()}`)
@@ -299,12 +311,44 @@ export class RelayServer extends EventEmitter {
     process.exit(1)
   }
 
+  /***
+   * initialize data from trusted paymasters.
+   * "Trusted" paymasters means that:
+   * - we trust their code not to alter the gas limits (getGasLimits returns constants)
+   * - we trust preRelayedCall to be consistent: off-chain call and on-chain calls should either both succeed
+   *    or both revert.
+   * - given that, we agree to give the requested acceptanceBudget (since breaking one of the above two "invariants"
+   *    is the only cases where the relayer will have to pay for this budget)
+   *
+   * @param paymasters list of trusted paymaster addresses
+   */
+  async _initTrustedPaymasters (paymasters: string[] = []): Promise<void> {
+    this.trustedPaymastersGasLimits.clear()
+    for (const paymasterAddress of paymasters) {
+      const paymaster = await this.contractInteractor._createPaymaster(paymasterAddress)
+      const gasLimits = await paymaster.getGasLimits().catch((e: Error) => {
+        throw new Error(`not a valid paymaster address in trustedPaymasters list: ${paymasterAddress}: ${e.message}`)
+      })
+      this.trustedPaymastersGasLimits.set(paymasterAddress.toLowerCase(), gasLimits)
+    }
+  }
+
+  _getPaymasterMaxAcceptanceBudget (paymaster?: string): IntString {
+    const limits = this.trustedPaymastersGasLimits.get(paymaster?.toLocaleLowerCase())
+    if (limits != null) {
+      return limits.acceptanceBudget
+    } else {
+      return this.config.maxAcceptanceBudget.toString()
+    }
+  }
+
   async init (): Promise<void> {
     if (this.initialized) {
       throw new Error('_init was already called')
     }
 
     await this.transactionManager._init()
+    await this._initTrustedPaymasters(this.config.trustedPaymasters)
     this.relayHubContract = await this.contractInteractor.relayHubInstance
 
     const relayHubAddress = this.relayHubContract.address
@@ -540,7 +584,7 @@ export class RelayServer extends EventEmitter {
   }
 
   _isTrustedPaymaster (paymaster: string): boolean {
-    return this.config.trustedPaymasters.map(it => it.toLowerCase()).includes(paymaster.toLowerCase())
+    return this.trustedPaymastersGasLimits.get(paymaster.toLocaleLowerCase()) != null
   }
 
   timeUnit (): number {

test/TestUtils.ts

@@ -100,8 +100,8 @@ export async function startRelay (
   }
   assert.ok(res, 'can\'t ping server')
   // eslint-disable-next-line @typescript-eslint/restrict-template-expressions
-  assert.ok(res.RelayServerAddress, `server returned unknown response ${res.toString()}`)
-  const relayManagerAddress = res.RelayManagerAddress
+  assert.ok(res.relayWorkerAddress, `server returned unknown response ${res.toString()}`)
+  const relayManagerAddress = res.relayManagerAddress
   console.log('Relay Server Address', relayManagerAddress)
   // @ts-ignore
   await web3.eth.sendTransaction({
@@ -124,10 +124,10 @@ export async function startRelay (
   let count = 25
   while (count-- > 0) {
     res = await http.getPingResponse(localhostOne)
-    if (res?.Ready) break
+    if (res?.ready) break
     await sleep(500)
   }
-  assert.ok(res.Ready, 'Timed out waiting for relay to get staked and registered')
+  assert.ok(res.ready, 'Timed out waiting for relay to get staked and registered')
 
   // TODO: this is temporary hack to make helper test work!!!
   // @ts-ignore

test/dummies/BadHttpClient.ts

@@ -23,14 +23,14 @@ export default class BadHttpClient extends HttpClient {
     this.stubPing = stubPing
   }
 
-  async getPingResponse (relayUrl: string): Promise<PingResponse> {
+  async getPingResponse (relayUrl: string, paymaster?: string): Promise<PingResponse> {
     if (this.failPing) {
       throw new Error(BadHttpClient.message)
     }
     if (this.stubPing != null) {
       return this.stubPing
     }
-    return await super.getPingResponse(relayUrl)
+    return await super.getPingResponse(relayUrl, paymaster)
   }
 
   async relayTransaction (relayUrl: string, request: RelayTransactionRequest): Promise<PrefixedHexString> {

test/relayclient/RelayClient.test.ts

@@ -237,7 +237,7 @@ contract('RelayClient', function (accounts) {
 
   describe('#_attemptRelay()', function () {
     const relayUrl = localhostOne
-    const RelayServerAddress = accounts[1]
+    const relayWorkerAddress = accounts[1]
     const relayManager = accounts[2]
     const relayOwner = accounts[3]
     let pingResponse: PingResponse
@@ -250,17 +250,17 @@ contract('RelayClient', function (accounts) {
         value: (2e18).toString()
       })
       await stakeManager.authorizeHubByOwner(relayManager, relayHub.address, { from: relayOwner })
-      await relayHub.addRelayWorkers([RelayServerAddress], { from: relayManager })
+      await relayHub.addRelayWorkers([relayWorkerAddress], { from: relayManager })
       await relayHub.registerRelayServer(2e16.toString(), '10', 'url', { from: relayManager })
       await relayHub.depositFor(paymaster.address, { value: (2e18).toString() })
       pingResponse = {
-        RelayServerAddress,
-        RelayManagerAddress: relayManager,
-        RelayHubAddress: relayManager,
-        MinGasPrice: '',
-        MaxAcceptanceBudget: 1e10.toString(),
-        Ready: true,
-        Version: ''
+        relayWorkerAddress: relayWorkerAddress,
+        relayManagerAddress: relayManager,
+        relayHubAddress: relayManager,
+        minGasPrice: '',
+        maxAcceptanceBudget: 1e10.toString(),
+        ready: true,
+        version: ''
       }
       relayInfo = {
         relayInfo: {