Merge pull request #100 from sideshift/master

Add SideShift.ai exchange plugin

Author: thehobbit85

src/index.js

@@ -1,5 +1,6 @@
 // @flow
 
+import { makeSideshiftPlugin } from '../lib/swap/sideshift'
 import { makeBitMaxPlugin } from './rate/bitmax.js'
 import { makeCoinbasePlugin } from './rate/coinbase.js'
 import { makeCoincapPlugin } from './rate/coincap.js'
@@ -42,6 +43,7 @@ const edgeCorePlugins = {
   foxExchange: makeFoxExchangePlugin,
   godex: makeGodexPlugin,
   shapeshift: makeShapeshiftPlugin,
+  sideshift: makeSideshiftPlugin,
   switchain: makeSwitchainPlugin,
   totle: makeTotlePlugin,
   transfer: makeTransferPlugin

src/swap/sideshift.js

@@ -0,0 +1,331 @@
+// @flow
+
+import { asBoolean, asNumber, asObject, asOptional, asString } from 'cleaners'
+import {
+  SwapAboveLimitError,
+  SwapBelowLimitError,
+  SwapPermissionError
+} from 'edge-core-js'
+import {
+  type EdgeCorePluginOptions,
+  type EdgeCurrencyWallet,
+  type EdgeFetchFunction,
+  type EdgeSpendInfo,
+  type EdgeSwapInfo,
+  type EdgeSwapPlugin,
+  type EdgeSwapQuote,
+  type EdgeSwapRequest,
+  SwapCurrencyError
+} from 'edge-core-js/types'
+
+import { makeSwapPluginQuote } from '../swap-helpers.js'
+
+// Invalid currency codes should *not* have transcribed codes
+// because currency codes with transcribed versions are NOT invalid
+const CURRENCY_CODE_TRANSCRIPTION = {
+  // Edge currencyCode: exchangeCurrencyCode
+  USDT: 'usdtErc20'
+}
+const SIDESHIFT_BASE_URL = 'https://sideshift.ai/api/v1'
+const pluginId = 'sideshift'
+const swapInfo: EdgeSwapInfo = {
+  pluginId,
+  displayName: 'SideShift.ai',
+  supportEmail: 'help@sideshift.ai'
+}
+
+async function getAddress(
+  wallet: EdgeCurrencyWallet,
+  currencyCode: string
+): Promise<string> {
+  const addressInfo = await wallet.getReceiveAddress({ currencyCode })
+  return addressInfo.segwitAddress ?? addressInfo.publicAddress
+}
+
+function getSafeCurrencyCode(request: EdgeSwapRequest) {
+  const { fromCurrencyCode, toCurrencyCode } = request
+
+  const safeFromCurrencyCode =
+    CURRENCY_CODE_TRANSCRIPTION[fromCurrencyCode] ||
+    fromCurrencyCode.toLowerCase()
+
+  const safeToCurrencyCode =
+    CURRENCY_CODE_TRANSCRIPTION[toCurrencyCode] || toCurrencyCode.toLowerCase()
+
+  return { safeFromCurrencyCode, safeToCurrencyCode }
+}
+
+async function checkQuoteError(
+  rate: Rate,
+  request: EdgeSwapRequest,
+  quoteErrorMessage: string
+) {
+  const { fromCurrencyCode, fromWallet } = request
+
+  if (quoteErrorMessage === 'Amount too low') {
+    const nativeMin = await fromWallet.denominationToNative(
+      rate.min,
+      fromCurrencyCode
+    )
+    throw new SwapBelowLimitError(swapInfo, nativeMin)
+  }
+
+  if (quoteErrorMessage === 'Amount too high') {
+    const nativeMax = await fromWallet.denominationToNative(
+      rate.max,
+      fromCurrencyCode
+    )
+    throw new SwapAboveLimitError(swapInfo, nativeMax)
+  }
+}
+
+const createSideshiftApi = (baseUrl: string, fetch: EdgeFetchFunction) => {
+  async function request<R>(
+    method: 'GET' | 'POST',
+    path: string,
+    body: ?{}
+  ): Promise<R> {
+    const url = `${baseUrl}${path}`
+
+    const reply = await (method === 'GET'
+      ? fetch(url)
+      : fetch(url, {
+          method,
+          headers: {
+            'Content-Type': 'application/json'
+          },
+          body: JSON.stringify(body)
+        }))
+
+    try {
+      return await reply.json()
+    } catch (e) {
+      throw new Error(`SideShift.ai returned error code ${reply.status}`)
+    }
+  }
+
+  return {
+    get: <R>(path: string): Promise<R> => request<R>('GET', path),
+    post: <R>(path: string, body: {}): Promise<R> =>
+      request<R>('POST', path, body)
+  }
+}
+
+const createFetchSwapQuote = (api: SideshiftApi, affiliateId: string) =>
+  async function fetchSwapQuote(
+    request: EdgeSwapRequest
+  ): Promise<EdgeSwapQuote> {
+    const permissions = asPermissions(await api.get<Permission>('/permissions'))
+
+    if (!permissions.createOrder || !permissions.createQuote) {
+      throw new SwapPermissionError(swapInfo, 'geoRestriction')
+    }
+
+    const [depositAddress, settleAddress] = await Promise.all([
+      getAddress(request.fromWallet, request.fromCurrencyCode),
+      getAddress(request.toWallet, request.toCurrencyCode)
+    ])
+
+    const { safeFromCurrencyCode, safeToCurrencyCode } = getSafeCurrencyCode(
+      request
+    )
+
+    const rate = asRate(
+      await api.get<typeof asRate>(
+        `/pairs/${safeFromCurrencyCode}/${safeToCurrencyCode}`
+      )
+    )
+
+    if (rate.error) {
+      throw new SwapCurrencyError(
+        swapInfo,
+        request.fromCurrencyCode,
+        request.toCurrencyCode
+      )
+    }
+
+    const quoteAmount = await (request.quoteFor === 'from'
+      ? request.fromWallet.nativeToDenomination(
+          request.nativeAmount,
+          request.fromCurrencyCode
+        )
+      : request.toWallet.nativeToDenomination(
+          request.nativeAmount,
+          request.toCurrencyCode
+        ))
+
+    const depositAmount =
+      request.quoteFor === 'from'
+        ? quoteAmount
+        : (parseFloat(quoteAmount) / rate.rate).toFixed(8).toString()
+
+    const fixedQuoteRequest = asFixedQuoteRequest({
+      depositMethod: safeFromCurrencyCode,
+      settleMethod: safeToCurrencyCode,
+      depositAmount
+    })
+
+    const fixedQuote = asFixedQuote(
+      await api.post<typeof asFixedQuote>('/quotes', fixedQuoteRequest)
+    )
+
+    if (fixedQuote.error) {
+      await checkQuoteError(rate, request, fixedQuote.error.message)
+    }
+
+    const orderRequest = asOrderRequest({
+      type: 'fixed',
+      quoteId: fixedQuote.id,
+      affiliateId,
+      settleAddress
+    })
+
+    const order = asOrder(
+      await api.post<typeof asOrder>('/orders', orderRequest)
+    )
+
+    const spendInfoAmount = await request.fromWallet.denominationToNative(
+      order.depositAmount,
+      request.fromCurrencyCode.toUpperCase()
+    )
+
+    const amountExpectedFromNative = await request.fromWallet.denominationToNative(
+      order.depositAmount,
+      request.fromCurrencyCode
+    )
+
+    const amountExpectedToNative = await request.fromWallet.denominationToNative(
+      order.settleAmount,
+      request.toCurrencyCode
+    )
+
+    const isEstimate = false
+
+    const spendInfo: EdgeSpendInfo = {
+      currencyCode: request.fromCurrencyCode,
+      spendTargets: [
+        {
+          nativeAmount: spendInfoAmount,
+          publicAddress: order.depositAddress.address
+        }
+      ],
+      networkFeeOption:
+        request.fromCurrencyCode.toUpperCase() === 'BTC' ? 'high' : 'standard',
+      swapData: {
+        orderId: order.orderId,
+        isEstimate,
+        payoutAddress: settleAddress,
+        payoutCurrencyCode: safeToCurrencyCode,
+        payoutNativeAmount: amountExpectedToNative,
+        payoutWalletId: request.toWallet.id,
+        plugin: { ...swapInfo },
+        refundAddress: depositAddress
+      }
+    }
+
+    const tx = await request.fromWallet.makeSpend(spendInfo)
+
+    return makeSwapPluginQuote(
+      request,
+      amountExpectedFromNative,
+      amountExpectedToNative,
+      tx,
+      settleAddress,
+      pluginId,
+      isEstimate,
+      new Date(order.expiresAtISO),
+      order.id
+    )
+  }
+
+export function makeSideshiftPlugin(
+  opts: EdgeCorePluginOptions
+): EdgeSwapPlugin {
+  const { io, initOptions } = opts
+
+  const api = createSideshiftApi(SIDESHIFT_BASE_URL, io.fetchCors || io.fetch)
+
+  const fetchSwapQuote = createFetchSwapQuote(api, initOptions.affiliateId)
+
+  return {
+    swapInfo,
+    fetchSwapQuote
+  }
+}
+
+interface SideshiftApi {
+  get: <R>(path: string) => Promise<R>;
+  post: <R>(path: string, body: {}) => Promise<R>;
+}
+
+interface Permission {
+  createOrder: boolean;
+  createQuote: boolean;
+}
+
+interface Rate {
+  rate: number;
+  min: string;
+  max: string;
+  error: { message: string } | typeof undefined;
+}
+
+const asPermissions = asObject({
+  createOrder: asBoolean,
+  createQuote: asBoolean
+})
+
+const asRate = asObject({
+  rate: asNumber,
+  min: asString,
+  max: asString,
+  error: asOptional(asObject({ message: asString }))
+})
+
+const asFixedQuoteRequest = asObject({
+  depositMethod: asString,
+  settleMethod: asString,
+  depositAmount: asString
+})
+
+const asFixedQuote = asObject({
+  createdAt: asString,
+  depositAmount: asString,
+  depositMethod: asString,
+  expiresAt: asString,
+  id: asString,
+  rate: asString,
+  settleAmount: asString,
+  settleMethod: asString,
+  error: asOptional(asObject({ message: asString }))
+})
+
+const asOrderRequest = asObject({
+  type: asString,
+  quoteId: asString,
+  affiliateId: asString,
+  sessionSecret: asOptional(asString),
+  settleAddress: asString
+})
+
+const asOrder = asObject({
+  createdAt: asString,
+  createdAtISO: asString,
+  expiresAt: asString,
+  expiresAtISO: asString,
+  depositAddress: asObject({
+    address: asString
+  }),
+  depositMethod: asString,
+  id: asString,
+  orderId: asString,
+  settleAddress: asObject({
+    address: asString
+  }),
+  settleMethod: asString,
+  depositMax: asString,
+  depositMin: asString,
+  quoteId: asString,
+  settleAmount: asString,
+  depositAmount: asString
+})