Use ContractKit to get addresses for Blockchain API

packages/blockchain-api/.env

@@ -1,7 +1,5 @@
 EXCHANGE_RATES_API=https://api.exchangeratesapi.io
-BLOCKSCOUT_API=https://alfajoresstaging-blockscout.celo-testnet.org/api
-CELO_GOLD_ADDRESS=0x1313e2f3EBef8f0d869EECEb796D55A066eEA863
-CELO_DOLLAR_ADDRESS=0x2df4dd6bd1b26a8503f763506bdb8e7cf165f69e
-FAUCET_ADDRESS=0xF4314cb9046bECe6AA54bb9533155434d0c76909
+BLOCKSCOUT_API=https://integration-blockscout.celo-testnet.org/api
+FAUCET_ADDRESS=0x47e172F6CfB6c7D01C1574fa3E2Be7CC73269D95
 VERIFICATION_REWARDS_ADDRESS=0xb4fdaf5f3cd313654aa357299ada901b1d2dd3b5
-ATTESTATIONS_ADDRESS=0x8b7649116f169d2d2aebb6ea1a77f0baf31f2811
+WEB3_PROVIDER_URL=https://integration-infura.celo-testnet.org/

packages/blockchain-api/app.alfajores.yaml

@@ -5,9 +5,6 @@ env_variables:
   DEPLOY_ENV: "alfajores"
   EXCHANGE_RATES_API: "https://api.exchangeratesapi.io"
   BLOCKSCOUT_API: "https://alfajores-blockscout.celo-testnet.org/api"
-  # Pull addresses from the build artifacts of the network in protocol/build
-  CELO_GOLD_ADDRESS: "0x11CD75C45638Ec9f41C0e8Df78fc756201E48ff2"
-  CELO_DOLLAR_ADDRESS: "0xd4b4fcaCAc9e23225680e89308E0a4C41Dd9C6B4"
   FAUCET_ADDRESS: "0xCEa3eF8e187490A9d85A1849D98412E5D27D1Bb3"
   VERIFICATION_REWARDS_ADDRESS: "0xb4fdaf5f3cd313654aa357299ada901b1d2dd3b5"
-  ATTESTATIONS_ADDRESS: "0x714f2879A4aa985508537f851FeBCfB26D7aF40D"
+  WEB3_PROVIDER_URL: "https://alfajores-infura.celo-testnet.org/"

packages/blockchain-api/app.alfajoresstaging.yaml

@@ -5,9 +5,6 @@ env_variables:
   DEPLOY_ENV: "alfajoresstaging"
   EXCHANGE_RATES_API: "https://api.exchangeratesapi.io"
   BLOCKSCOUT_API: "https://alfajoresstaging-blockscout.celo-testnet.org/api"
-  # Pull addresses from the build artifacts of the network in protocol/build
-  CELO_GOLD_ADDRESS: "0x1313e2f3EBef8f0d869EECEb796D55A066eEA863"
-  CELO_DOLLAR_ADDRESS: "0x2dF4dD6Bd1b26a8503F763506bdB8e7cf165f69E"
   FAUCET_ADDRESS: "0xF4314cb9046bECe6AA54bb9533155434d0c76909"
   VERIFICATION_REWARDS_ADDRESS: "0xb4fdaf5f3cd313654aa357299ada901b1d2dd3b5"
-  ATTESTATIONS_ADDRESS: "0x8B7649116f169D2D2aeBB6Ea1A77F0baF31F2811"
+  WEB3_PROVIDER_URL: "https://alfajoresstaging-infura.celo-testnet.org/"

packages/blockchain-api/app.integration.yaml

@@ -5,9 +5,6 @@ env_variables:
   DEPLOY_ENV: "integration"
   EXCHANGE_RATES_API: "https://api.exchangeratesapi.io"
   BLOCKSCOUT_API: "https://integration-blockscout.celo-testnet.org/api"
-  # Pull addresses from the build artifacts of the network in protocol/build
-  CELO_GOLD_ADDRESS: "0x9102eCD93ac8D66bAc3D397BF52bc57Ee34Bcb87"
-  CELO_DOLLAR_ADDRESS: "0x47736AB66b892b0FCCb5c7d69B879C6141F6E80c"
   FAUCET_ADDRESS: "0x47e172F6CfB6c7D01C1574fa3E2Be7CC73269D95"
   VERIFICATION_REWARDS_ADDRESS: "0xb4fdaf5f3cd313654aa357299ada901b1d2dd3b5"
-  ATTESTATIONS_ADDRESS: "0xD2C0894D551D4C810Dc5CB55081c0b7BE965A118"
+  WEB3_PROVIDER_URL: "https://integration-infura.celo-testnet.org/"

packages/blockchain-api/app.pilot.yaml

@@ -5,9 +5,6 @@ env_variables:
   DEPLOY_ENV: "pilot"
   EXCHANGE_RATES_API: "https://api.exchangeratesapi.io"
   BLOCKSCOUT_API: "https://pilot-blockscout.celo-testnet.org/api"
-  # Pull addresses from the build artifacts of the network in protocol/build
-  CELO_GOLD_ADDRESS: "0xa69c3D18a74B3FD5F8aDA748428d0bfF8c5387Fe"
-  CELO_DOLLAR_ADDRESS: "0x996e24D7791A182f237635018c49E30cdA8FBa5e"
   FAUCET_ADDRESS: "0x387bCb16Bfcd37AccEcF5c9eB2938E30d3aB8BF2"
   VERIFICATION_REWARDS_ADDRESS: "0xb4fdaf5f3cd313654aa357299ada901b1d2dd3b5"
-  ATTESTATIONS_ADDRESS: "0x2cDEc3af5727dF2d490cF6068980E67dc6c19438"
+  WEB3_PROVIDER_URL: "https://pilot-infura.celo-testnet.org/"

packages/blockchain-api/app.pilotstaging.yaml

@@ -5,9 +5,6 @@ env_variables:
   DEPLOY_ENV: "pilotstaging"
   EXCHANGE_RATES_API: "https://api.exchangeratesapi.io"
   BLOCKSCOUT_API: "https://pilotstaging-blockscout.celo-testnet.org/api"
-  # Pull addresses from the build artifacts of the network in protocol/build
-  CELO_GOLD_ADDRESS: "0x2c9829C36c9D0802f04C6a06c423e132a3Ae1767"
-  CELO_DOLLAR_ADDRESS: "0x21C4A2C97eaE0c0E8c630FB3529F7718Fa37eCC1"
   FAUCET_ADDRESS: "0x545DEBe3030B570731EDab192640804AC8Cf65CA"
   VERIFICATION_REWARDS_ADDRESS: "0xb4fdaf5f3cd313654aa357299ada901b1d2dd3b5"
-  ATTESTATIONS_ADDRESS: "0xE3085194DFf8230EBccd5D6C55C59D52Fd9D5b90"
+  WEB3_PROVIDER_URL: "https://pilotstaging-infura.celo-testnet.org/"

packages/blockchain-api/package.json

@@ -16,6 +16,7 @@
     "deploy": "./deploy.sh"
   },
   "dependencies": {
+    "@celo/contractkit": "0.1.6",
     "apollo-datasource-rest": "^0.3.1",
     "apollo-server-express": "^2.4.2",
     "bignumber.js": "^7.2.0",

packages/blockchain-api/src/blockscout.ts

@@ -1,14 +1,8 @@
 import { RESTDataSource } from 'apollo-datasource-rest'
 import BigNumber from 'bignumber.js'
-import {
-  ATTESTATIONS_ADDRESS,
-  BLOCKSCOUT_API,
-  CONTRACT_SYMBOL_MAPPING,
-  FAUCET_ADDRESS,
-  VERIFICATION_REWARDS_ADDRESS,
-} from './config'
+import { BLOCKSCOUT_API, FAUCET_ADDRESS, VERIFICATION_REWARDS_ADDRESS } from './config'
 import { EventArgs, EventInterface, EventTypes, TransferEvent } from './schema'
-import { formatCommentString } from './utils'
+import { formatCommentString, getContractAddresses } from './utils'
 
 // to get rid of 18 extra 0s in the values
 const WEI_PER_GOLD = Math.pow(10, 18)
@@ -51,6 +45,8 @@ export interface BlockscoutTransaction {
 }
 
 export class BlockscoutAPI extends RESTDataSource {
+  tokenAddressMapping: { [key: string]: string } | undefined
+  attestationsAddress: string | undefined
   constructor() {
     super()
     this.baseURL = BLOCKSCOUT_API
@@ -67,6 +63,43 @@ export class BlockscoutAPI extends RESTDataSource {
     return result
   }
 
+  async ensureTokenAddresses() {
+    if (this.tokenAddressMapping && this.attestationsAddress) {
+      // Already got addresses
+      return
+    } else {
+      const addresses = await getContractAddresses()
+      this.attestationsAddress = addresses.attestationsAddress
+      this.tokenAddressMapping = addresses.tokenAddressMapping
+    }
+  }
+
+  getTokenAtAddress(tokenAddress: string) {
+    if (this.tokenAddressMapping) {
+      const lowerCaseTokenAddress = tokenAddress.toLowerCase()
+      if (lowerCaseTokenAddress in this.tokenAddressMapping) {
+        return this.tokenAddressMapping[lowerCaseTokenAddress]
+      } else {
+        console.info('Token addresses mapping: ' + JSON.stringify(this.tokenAddressMapping))
+        throw new Error(
+          'No token corresponding to ' +
+            lowerCaseTokenAddress +
+            '. Check web3 provider is for correct network.'
+        )
+      }
+    } else {
+      throw new Error('Cannot find tokenAddressMapping')
+    }
+  }
+
+  getAttestationAddress() {
+    if (this.attestationsAddress) {
+      return this.attestationsAddress
+    } else {
+      throw new Error('Cannot find attestation address')
+    }
+  }
+
   // LIMITATION:
   // This function will only return Gold transfers that happened via the GoldToken
   // contract. Any native transfers of Gold will be omitted because of how blockscout
@@ -89,6 +122,7 @@ export class BlockscoutAPI extends RESTDataSource {
       txHashToEventTransactions.set(tx.hash, currentTX)
     }
 
+    await this.ensureTokenAddresses()
     // Generate final events
     txHashToEventTransactions.forEach((transactions: BlockscoutTransaction[], txhash: string) => {
       // Exchange events have two corresponding transactions (in and out)
@@ -106,9 +140,9 @@ export class BlockscoutAPI extends RESTDataSource {
           type: EventTypes.EXCHANGE,
           timestamp: new BigNumber(inEvent.timeStamp).toNumber(),
           block: new BigNumber(inEvent.blockNumber).toNumber(),
-          inSymbol: CONTRACT_SYMBOL_MAPPING[inEvent.contractAddress.toLowerCase()],
+          inSymbol: this.getTokenAtAddress(inEvent.contractAddress),
           inValue: new BigNumber(inEvent.value).dividedBy(WEI_PER_GOLD).toNumber(),
-          outSymbol: CONTRACT_SYMBOL_MAPPING[outEvent.contractAddress.toLowerCase()],
+          outSymbol: this.getTokenAtAddress(outEvent.contractAddress),
           outValue: new BigNumber(outEvent.value).dividedBy(WEI_PER_GOLD).toNumber(),
           hash: txhash,
         })
@@ -122,7 +156,8 @@ export class BlockscoutAPI extends RESTDataSource {
         const [type, address] = resolveTransferEventType(
           userAddress,
           eventToAddress,
-          eventFromAddress
+          eventFromAddress,
+          this.getAttestationAddress()
         )
         events.push({
           type,
@@ -131,7 +166,7 @@ export class BlockscoutAPI extends RESTDataSource {
           value: new BigNumber(event.value).dividedBy(WEI_PER_GOLD).toNumber(),
           address,
           comment,
-          symbol: CONTRACT_SYMBOL_MAPPING[event.contractAddress.toLowerCase()] || 'unknown',
+          symbol: this.getTokenAtAddress(event.contractAddress) || 'unknown',
           hash: txhash,
         })
       }
@@ -148,6 +183,7 @@ export class BlockscoutAPI extends RESTDataSource {
   async getFeedRewards(args: EventArgs) {
     const rewards: TransferEvent[] = []
     const rawTransactions = await this.getTokenTransactions(args)
+    await this.ensureTokenAddresses()
     for (const t of rawTransactions) {
       // Only include verification rewards transfers
       if (t.from.toLowerCase() !== VERIFICATION_REWARDS_ADDRESS) {
@@ -160,7 +196,7 @@ export class BlockscoutAPI extends RESTDataSource {
         value: new BigNumber(t.value).dividedBy(WEI_PER_GOLD).toNumber(),
         address: VERIFICATION_REWARDS_ADDRESS,
         comment: t.input ? formatCommentString(t.input) : '',
-        symbol: CONTRACT_SYMBOL_MAPPING[t.contractAddress],
+        symbol: this.getTokenAtAddress(t.contractAddress),
         hash: t.hash,
       })
     }
@@ -176,13 +212,14 @@ export class BlockscoutAPI extends RESTDataSource {
 function resolveTransferEventType(
   userAddress: string,
   eventToAddress: string,
-  eventFromAddress: string
+  eventFromAddress: string,
+  attestationsAddress: string
 ): [EventTypes, string] {
   if (eventToAddress === userAddress && eventFromAddress === FAUCET_ADDRESS) {
     return [EventTypes.FAUCET, FAUCET_ADDRESS]
   }
-  if (eventToAddress === ATTESTATIONS_ADDRESS && eventFromAddress === userAddress) {
-    return [EventTypes.VERIFICATION_FEE, ATTESTATIONS_ADDRESS]
+  if (eventToAddress === attestationsAddress && eventFromAddress === userAddress) {
+    return [EventTypes.VERIFICATION_FEE, attestationsAddress]
   }
   if (eventToAddress === userAddress && eventFromAddress === VERIFICATION_REWARDS_ADDRESS) {
     return [EventTypes.VERIFICATION_REWARD, VERIFICATION_REWARDS_ADDRESS]

packages/blockchain-api/src/config.ts

@@ -3,16 +3,9 @@ import dotenv from 'dotenv'
 // Load environment variables from .env file
 dotenv.config()
 
-export const CONTRACT_SYMBOL_MAPPING: { [key: string]: string } = {
-  // GOLD_CONTRACT_ADDRESS
-  [(process.env.CELO_GOLD_ADDRESS as string).toLowerCase()]: 'Celo Gold',
-  // DOLLAR_CONTRACT_ADDRESS
-  [(process.env.CELO_DOLLAR_ADDRESS as string).toLowerCase()]: 'Celo Dollar',
-}
-
 export const EXCHANGE_RATES_API = (process.env.EXCHANGE_RATES_API as string).toLowerCase()
 export const BLOCKSCOUT_API = (process.env.BLOCKSCOUT_API as string).toLowerCase()
 export const FAUCET_ADDRESS = (process.env.FAUCET_ADDRESS as string).toLowerCase()
 export const VERIFICATION_REWARDS_ADDRESS = (process.env
   .VERIFICATION_REWARDS_ADDRESS as string).toLowerCase()
-export const ATTESTATIONS_ADDRESS = (process.env.ATTESTATIONS_ADDRESS as string).toLowerCase()
+export const WEB3_PROVIDER_URL = process.env.WEB3_PROVIDER_URL

packages/blockchain-api/src/utils.ts

@@ -1,6 +1,9 @@
 /* tslint:disable:no-console */
+import { CeloContract, ContractKit, newKitFromWeb3 } from '@celo/contractkit'
 import * as utf8 from 'utf8'
+import Web3 from 'web3'
 import coder from 'web3-eth-abi'
+import { WEB3_PROVIDER_URL } from './config'
 
 export function randomTimestamp() {
   const start = new Date(2018, 0, 1)
@@ -40,3 +43,55 @@ export function formatCommentString(functionCallHex: string): string {
 export function formatDateString(date: Date) {
   return date.toISOString().split('T')[0]
 }
+
+let goldTokenAddress: string
+let stableTokenAddress: string
+let attestationsAddress: string
+let tokenAddressMapping: { [key: string]: string }
+export async function getContractAddresses() {
+  if (goldTokenAddress && stableTokenAddress && attestationsAddress) {
+    console.info('Already got token addresses')
+    return { tokenAddressMapping, attestationsAddress }
+  }
+  try {
+    const kit = await getContractKit()
+    goldTokenAddress = (await kit.registry.addressFor(CeloContract.StableToken)).toLowerCase()
+    stableTokenAddress = (await kit.registry.addressFor(CeloContract.GoldToken)).toLowerCase()
+    attestationsAddress = (await kit.registry.addressFor(CeloContract.Attestations)).toLowerCase()
+    tokenAddressMapping = {
+      [goldTokenAddress]: 'Celo Gold',
+      [stableTokenAddress]: 'Celo Dollar',
+    }
+    console.info(
+      'Got token addresses. Attestations: ' +
+        attestationsAddress +
+        ' Token mapping: ' +
+        JSON.stringify(tokenAddressMapping)
+    )
+    return { tokenAddressMapping, attestationsAddress }
+  } catch (e) {
+    console.error('@getContractAddresses() error', e)
+    throw new Error('Unable to fetch contract addresses')
+  }
+}
+
+let contractKit: ContractKit
+export async function getContractKit(): Promise<ContractKit> {
+  if (contractKit && (await contractKit.isListening())) {
+    // Already connected
+    return contractKit
+  }
+  try {
+    if (WEB3_PROVIDER_URL) {
+      const httpProvider = new Web3.providers.HttpProvider(WEB3_PROVIDER_URL)
+      const web3 = new Web3(httpProvider)
+      contractKit = newKitFromWeb3(web3)
+      return contractKit
+    } else {
+      throw new Error('Missing web3 provider URL, will not be able to fetch contract addresses.')
+    }
+  } catch (e) {
+    console.error('@getContractKit() error', e)
+    throw new Error('Failed to create contractKit instance')
+  }
+}

packages/blockchain-api/test/blockscout.test.ts

@@ -22,6 +22,22 @@ jest.mock('../src/config.ts', () => {
   }
 })
 
+jest.mock('../src/utils.ts', () => {
+  const contractGetter = jest.fn()
+  const tokenAddressMapping: { [key: string]: string } = {
+    ['0x000000000000000000000000000000000000gold']: 'Celo Gold',
+    ['0x0000000000000000000000000000000000dollar']: 'Celo Dollar',
+  }
+  contractGetter.mockReturnValue({
+    tokenAddressMapping,
+    attestationsAddress: '0x0000000000000000000000000000000000a77357',
+  })
+  return {
+    ...jest.requireActual('../src/utils.ts'),
+    getContractAddresses: contractGetter,
+  }
+})
+
 describe('Blockscout', () => {
   let blockscoutAPI: BlockscoutAPI