feat: add approval needed to lib (shapeshift#95)

* add approvalNeeded to ZrxSwapper

* add rest of approvalNeeded and tests; extract web3 logic to a helper function

* add throw error when passed wrong chain to approvalNeeded

packages/swapper/src/api.ts

@@ -1,6 +1,8 @@
 import { HDWallet } from '@shapeshiftoss/hdwallet-core'
 import {
   Asset,
+  ApprovalNeededInput,
+  ApprovalNeededOutput,
   BuildQuoteTxInput,
   GetQuoteInput,
   Quote,
@@ -65,4 +67,10 @@ export interface Swapper {
    * @param wallet
    */
   executeQuote(args: ExecQuoteInput): Promise<ExecQuoteOutput>
+
+  /**
+   * Get a boolean if a quote needs approval
+   */
+
+  approvalNeeded(args: ApprovalNeededInput): Promise<ApprovalNeededOutput>
 }

packages/swapper/src/swappers/thorchain/ThorchainSwapper.ts

@@ -1,5 +1,6 @@
 import {
   Asset,
+  ApprovalNeededOutput,
   SwapperType,
   Quote,
   ExecQuoteOutput,
@@ -28,13 +29,14 @@ export class ThorchainSwapper implements Swapper {
 
   getMinMax(input: GetQuoteInput): Promise<MinMaxOutput> {
     console.info(input)
-    throw new Error('Method not implemented.')
+    throw new Error('ThorchainSwapper: getMinMax unimplemented')
   }
 
   getAvailableAssets(assets: Asset[]): Asset[] {
     console.info(assets)
     throw new Error('ThorchainSwapper: getAvailableAssets unimplemented')
   }
+
   canTradePair(sellAsset: Asset, buyAsset: Asset): boolean {
     console.info(sellAsset, buyAsset)
     throw new Error('ThorchainSwapper: canTradePair unimplemented')
@@ -45,6 +47,10 @@ export class ThorchainSwapper implements Swapper {
   }
 
   getDefaultPair(): Partial<Asset>[] {
-    throw new Error('Method not implemented.')
+    throw new Error('ThorchainSwapper: getDefaultPair unimplemented')
+  }
+
+  async approvalNeeded(): Promise<ApprovalNeededOutput> {
+    throw new Error('ThorchainSwapper: approvalNeeded unimplemented')
   }
 }

packages/swapper/src/swappers/zrx/ZrxSwapper.ts

@@ -1,6 +1,8 @@
 import Web3 from 'web3'
 import {
   Asset,
+  ApprovalNeededInput,
+  ApprovalNeededOutput,
   BuildQuoteTxInput,
   ChainTypes,
   GetQuoteInput,
@@ -17,6 +19,7 @@ import { getZrxQuote } from './getQuote/getQuote'
 import { getUsdRate } from './utils/helpers/helpers'
 import { getMinMax } from './getMinMax/getMinMax'
 import { executeQuote } from './executeQuote/executeQuote'
+import { approvalNeeded } from './approvalNeeded/approvalNeeded'
 
 export type ZrxSwapperDeps = {
   adapterManager: ChainAdapterManager
@@ -76,4 +79,8 @@ export class ZrxSwapper implements Swapper {
   async executeQuote(args: ExecQuoteInput): Promise<ExecQuoteOutput> {
     return executeQuote(this.deps, args)
   }
+
+  async approvalNeeded(args: ApprovalNeededInput): Promise<ApprovalNeededOutput> {
+    return approvalNeeded(this.deps, args)
+  }
 }

packages/swapper/src/swappers/zrx/approvalNeeded/approvalNeeded.test.ts

@@ -0,0 +1,117 @@
+import Web3 from 'web3'
+import { HDWallet } from '@shapeshiftoss/hdwallet-core'
+import { ChainTypes } from '@shapeshiftoss/types'
+import { ChainAdapterManager } from '@shapeshiftoss/chain-adapters'
+import { approvalNeeded } from './approvalNeeded'
+import { setupQuote } from '../utils/test-data/setupSwapQuote'
+import { zrxService } from '../utils/zrxService'
+import { APPROVAL_GAS_LIMIT } from '../utils/constants'
+
+jest.mock('web3')
+jest.mock('axios', () => ({
+  create: jest.fn(() => ({
+    get: jest.fn()
+  }))
+}))
+
+// @ts-ignore
+Web3.mockImplementation(() => ({
+  eth: {
+    Contract: jest.fn(() => ({
+      methods: {
+        allowance: jest.fn(() => ({
+          call: jest.fn()
+        }))
+      }
+    }))
+  }
+}))
+
+const setup = () => {
+  const unchainedUrls = {
+    [ChainTypes.Ethereum]: 'http://localhost:31300/api/v1'
+  }
+  const ethNodeUrl = 'http://localhost:1000'
+  const adapterManager = new ChainAdapterManager(unchainedUrls)
+  const web3Provider = new Web3.providers.HttpProvider(ethNodeUrl)
+  const web3 = new Web3(web3Provider)
+
+  return { web3, adapterManager }
+}
+
+describe('approvalNeeded', () => {
+  const { web3, adapterManager } = setup()
+  const args = { web3, adapterManager }
+  const walletAddress = '0xc770eefad204b5180df6a14ee197d99d808ee52d'
+  const wallet = ({
+    ethGetAddress: jest.fn(() => Promise.resolve(walletAddress))
+  } as unknown) as HDWallet
+
+  const { quoteInput, sellAsset } = setupQuote()
+
+  it('returns false if sellAsset symbol is ETH', async () => {
+    const input = {
+      quote: { ...quoteInput, sellAsset: { ...sellAsset, symbol: 'ETH' } },
+      wallet
+    }
+
+    expect(await approvalNeeded(args, input)).toEqual({ approvalNeeded: false })
+  })
+
+  it('throws an error if sellAsset chain is not ETH', async () => {
+    const input = {
+      quote: { ...quoteInput, sellAsset: { ...sellAsset, chain: ChainTypes.Bitcoin } },
+      wallet
+    }
+
+    await expect(approvalNeeded(args, input)).rejects.toThrow(
+      'ZrxSwapper:approvalNeeded only Ethereum chain type is supported'
+    )
+  })
+
+  it('returns false if allowanceOnChain is greater than quote.sellAmount', async () => {
+    const allowanceOnChain = '50'
+    const data = { gasPrice: '1000', allowanceTarget: '10' }
+    const input = {
+      quote: { ...quoteInput, sellAmount: '10' },
+      wallet
+    }
+    ;(web3.eth.Contract as jest.Mock<unknown>).mockImplementation(() => ({
+      methods: {
+        allowance: jest.fn(() => ({
+          call: jest.fn(() => allowanceOnChain)
+        }))
+      }
+    }))
+    ;(zrxService.get as jest.Mock<unknown>).mockReturnValue(Promise.resolve({ data }))
+
+    expect(await approvalNeeded(args, input)).toEqual({
+      approvalNeeded: false,
+      gas: APPROVAL_GAS_LIMIT,
+      gasPrice: data.gasPrice
+    })
+  })
+
+  it('returns true if allowanceOnChain is less than quote.sellAmount', async () => {
+    const allowanceOnChain = '5'
+    const data = { gasPrice: '1000', allowanceTarget: '10' }
+    const input = {
+      quote: { ...quoteInput, sellAmount: '10' },
+      wallet
+    }
+    ;(web3.eth.Contract as jest.Mock<unknown>).mockImplementation(() => ({
+      methods: {
+        allowance: jest.fn(() => ({
+          call: jest.fn(() => allowanceOnChain)
+        }))
+      }
+    }))
+    ;(zrxService.get as jest.Mock<unknown>).mockReturnValue(Promise.resolve({ data }))
+
+    expect(await approvalNeeded(args, input)).toEqual({
+      approvalNeeded: true,
+      gas: APPROVAL_GAS_LIMIT,
+      gasPrice: data.gasPrice
+    })
+  })
+})

packages/swapper/src/swappers/zrx/approvalNeeded/approvalNeeded.ts

@@ -0,0 +1,82 @@
+import { BigNumber } from 'bignumber.js'
+import { AxiosResponse } from 'axios'
+import { ChainAdapter } from '@shapeshiftoss/chain-adapters'
+import {
+  ApprovalNeededInput,
+  ApprovalNeededOutput,
+  ChainTypes,
+  QuoteResponse
+} from '@shapeshiftoss/types'
+import {
+  AFFILIATE_ADDRESS,
+  APPROVAL_BUY_AMOUNT,
+  APPROVAL_GAS_LIMIT,
+  DEFAULT_ETH_PATH,
+  DEFAULT_SLIPPAGE
+} from '../utils/constants'
+
+import { SwapError } from '../../../api'
+import { ZrxSwapperDeps } from '../ZrxSwapper'
+import { zrxService } from '../utils/zrxService'
+import { getERC20Allowance } from '../utils/helpers/helpers'
+import { erc20AllowanceAbi } from '../utils/abi/erc20Allowance-abi'
+
+export async function approvalNeeded(
+  { adapterManager, web3 }: ZrxSwapperDeps,
+  { quote, wallet }: ApprovalNeededInput
+): Promise<ApprovalNeededOutput> {
+  const { sellAsset } = quote
+
+  if (sellAsset.symbol === 'ETH') {
+    return { approvalNeeded: false }
+  }
+
+  if (sellAsset.chain !== ChainTypes.Ethereum) {
+    throw new SwapError('ZrxSwapper:approvalNeeded only Ethereum chain type is supported')
+  }
+
+  const adapter: ChainAdapter = adapterManager.byChain(sellAsset.chain)
+  const receiveAddress = await adapter.getAddress({ wallet, path: DEFAULT_ETH_PATH })
+
+  /**
+   * /swap/v1/quote
+   * params: {
+   *   sellToken: contract address (or symbol) of token to sell
+   *   buyToken: contractAddress (or symbol) of token to buy
+   *   sellAmount?: integer string value of the smallest increment of the sell token
+   *   buyAmount?: integer string value of the smallest incremtent of the buy token
+   * }
+   */
+  const quoteResponse: AxiosResponse<QuoteResponse> = await zrxService.get<QuoteResponse>(
+    '/swap/v1/quote',
+    {
+      params: {
+        buyToken: 'ETH',
+        sellToken: quote.sellAsset.tokenId || quote.sellAsset.symbol || quote.sellAsset.chain,
+        buyAmount: APPROVAL_BUY_AMOUNT,
+        takerAddress: receiveAddress,
+        slippagePercentage: DEFAULT_SLIPPAGE,
+        skipValidation: true,
+        affiliateAddress: AFFILIATE_ADDRESS
+      }
+    }
+  )
+  const { data } = quoteResponse
+
+  const allowanceResult = getERC20Allowance(
+    { web3, erc20AllowanceAbi },
+    {
+      tokenId: quote.sellAsset.tokenId as string,
+      spenderAddress: data.allowanceTarget as string,
+      ownerAddress: receiveAddress
+    }
+  )
+
+  const allowanceOnChain = new BigNumber(allowanceResult || '0')
+
+  return {
+    approvalNeeded: allowanceOnChain.lt(new BigNumber(quote.sellAmount || 1)),
+    gas: APPROVAL_GAS_LIMIT,
+    gasPrice: data.gasPrice
+  }
+}

packages/swapper/src/swappers/zrx/buildQuoteTx/buildQuoteTx.ts

@@ -3,10 +3,10 @@ import { AxiosResponse } from 'axios'
 import * as rax from 'retry-axios'
 import { ChainAdapter } from '@shapeshiftoss/chain-adapters'
 import { SwapError } from '../../..'
-import { Quote, BuildQuoteTxInput } from '@shapeshiftoss/types'
+import { Quote, QuoteResponse, BuildQuoteTxInput } from '@shapeshiftoss/types'
 import { ZrxSwapperDeps } from '../ZrxSwapper'
 import { applyAxiosRetry } from '../utils/applyAxiosRetry'
-import { erc20AllowanceAbi } from '../utils/abi/erc20-abi'
+import { erc20AllowanceAbi } from '../utils/abi/erc20Allowance-abi'
 import { normalizeAmount, getAllowanceRequired } from '../utils/helpers/helpers'
 import { zrxService } from '../utils/zrxService'
 import {
@@ -18,30 +18,6 @@ import {
   MAX_SLIPPAGE
 } from '../utils/constants'
 
-type LiquiditySource = {
-  name: string
-  proportion: string
-}
-
-type QuoteResponse = {
-  price: string
-  guaranteedPrice: string
-  to: string
-  data?: string
-  value?: string
-  gas?: string
-  estimatedGas?: string
-  gasPrice?: string
-  protocolFee?: string
-  minimumProtocolFee?: string
-  buyTokenAddress?: string
-  sellTokenAddress?: string
-  buyAmount?: string
-  sellAmount?: string
-  allowanceTarget?: string
-  sources?: Array<LiquiditySource>
-}
-
 export async function buildQuoteTx(
   { adapterManager, web3 }: ZrxSwapperDeps,
   { input, wallet }: BuildQuoteTxInput

packages/swapper/src/swappers/zrx/utils/constants.ts

@@ -14,3 +14,4 @@ export const DEFAULT_SLIPPAGE = '3.0' // 3%
 export const MAX_SLIPPAGE = '30.0' // 30%
 export const DEFAULT_ETH_PATH = `m/44'/60'/0'/0/0` // TODO: remove when `adapter.getAddress` changes to take an account instead of default path
 export const AFFILIATE_ADDRESS = '0xc770eefad204b5180df6a14ee197d99d808ee52d'
+export const APPROVAL_BUY_AMOUNT = '100000000000000000' // A valid buy amount - 0.1 ETH

packages/swapper/src/swappers/zrx/utils/helpers/helpers.test.ts

@@ -1,12 +1,13 @@
 import Web3 from 'web3'
 import BigNumber from 'bignumber.js'
 import { setupQuote } from '../test-data/setupSwapQuote'
-import { erc20AllowanceAbi } from '../../utils/abi/erc20-abi'
+import { erc20AllowanceAbi } from '../abi/erc20Allowance-abi'
 import { normalizeAmount, getAllowanceRequired, getUsdRate } from '../helpers/helpers'
 import { zrxService } from '../zrxService'
 
 jest.mock('web3')
 const axios = jest.createMockFromModule('axios')
+
 //@ts-ignore
 axios.create = jest.fn(() => axios)
 jest.mock('../zrxService')

packages/swapper/src/swappers/zrx/utils/helpers/helpers.ts

@@ -13,6 +13,17 @@ export type GetAllowanceRequiredArgs = {
   erc20AllowanceAbi: AbiItem[]
 }
 
+export type GetERC20AllowanceDeps = {
+  erc20AllowanceAbi: AbiItem[]
+  web3: Web3
+}
+
+export type GetERC20AllowanceArgs = {
+  tokenId: string
+  ownerAddress: string
+  spenderAddress: string
+}
+
 /**
  * Very large amounts like those found in ERC20s with a precision of 18 get converted
  * to exponential notation ('1.6e+21') in javascript. The 0x api doesn't play well with
@@ -26,6 +37,14 @@ export const normalizeAmount = (amount: string | undefined): string | undefined
   return new BigNumber(amount).toNumber().toLocaleString('fullwide', { useGrouping: false })
 }
 
+export const getERC20Allowance = (
+  { erc20AllowanceAbi, web3 }: GetERC20AllowanceDeps,
+  { tokenId, ownerAddress, spenderAddress }: GetERC20AllowanceArgs
+) => {
+  const erc20Contract = new web3.eth.Contract(erc20AllowanceAbi, tokenId)
+  return erc20Contract.methods.allowance(ownerAddress, spenderAddress).call()
+}
+
 export const getAllowanceRequired = async ({
   quote,
   web3,
@@ -35,11 +54,14 @@ export const getAllowanceRequired = async ({
     return new BigNumber(0)
   }
 
-  const ownerAddress = quote.receiveAddress
-  const spenderAddress = quote.allowanceContract
+  const ownerAddress = quote.receiveAddress as string
+  const spenderAddress = quote.allowanceContract as string
+  const tokenId = quote.sellAsset.tokenId as string
 
-  const erc20Contract = new web3.eth.Contract(erc20AllowanceAbi, quote.sellAsset.tokenId)
-  const allowanceOnChain = erc20Contract.methods.allowance(ownerAddress, spenderAddress).call()
+  const allowanceOnChain = getERC20Allowance(
+    { web3, erc20AllowanceAbi },
+    { ownerAddress, spenderAddress, tokenId }
+  )
 
   if (allowanceOnChain === '0') {
     return new BigNumber(quote.sellAmount || 0)