@swipewallet/venus-js
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A JavaScript SDK for Ethereum and the Venus Protocol.
193 lines • 10.9 kB
JavaScript
"use strict";
/**
* @file Price Feed
* @desc These methods facilitate interactions with the Open Price Feed smart
* contracts.
*/
var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) {
function adopt(value) { return value instanceof P ? value : new P(function (resolve) { resolve(value); }); }
return new (P || (P = Promise))(function (resolve, reject) {
function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } }
function rejected(value) { try { step(generator["throw"](value)); } catch (e) { reject(e); } }
function step(result) { result.done ? resolve(result.value) : adopt(result.value).then(fulfilled, rejected); }
step((generator = generator.apply(thisArg, _arguments || [])).next());
});
};
var __generator = (this && this.__generator) || function (thisArg, body) {
var _ = { label: 0, sent: function() { if (t[0] & 1) throw t[1]; return t[1]; }, trys: [], ops: [] }, f, y, t, g;
return g = { next: verb(0), "throw": verb(1), "return": verb(2) }, typeof Symbol === "function" && (g[Symbol.iterator] = function() { return this; }), g;
function verb(n) { return function (v) { return step([n, v]); }; }
function step(op) {
if (f) throw new TypeError("Generator is already executing.");
while (_) try {
if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
if (y = 0, t) op = [op[0] & 2, t.value];
switch (op[0]) {
case 0: case 1: t = op; break;
case 4: _.label++; return { value: op[1], done: false };
case 5: _.label++; y = op[1]; op = [0]; continue;
case 7: op = _.ops.pop(); _.trys.pop(); continue;
default:
if (!(t = _.trys, t = t.length > 0 && t[t.length - 1]) && (op[0] === 6 || op[0] === 2)) { _ = 0; continue; }
if (op[0] === 3 && (!t || (op[1] > t[0] && op[1] < t[3]))) { _.label = op[1]; break; }
if (op[0] === 6 && _.label < t[1]) { _.label = t[1]; t = op; break; }
if (t && _.label < t[2]) { _.label = t[2]; _.ops.push(op); break; }
if (t[2]) _.ops.pop();
_.trys.pop(); continue;
}
op = body.call(thisArg, _);
} catch (e) { op = [6, e]; y = 0; } finally { f = t = 0; }
if (op[0] & 5) throw op[1]; return { value: op[0] ? op[1] : void 0, done: true };
}
};
exports.__esModule = true;
exports.getPrice = void 0;
var eth = require("./eth");
var helpers_1 = require("./helpers");
var constants_1 = require("./constants");
var bignumber_1 = require("@ethersproject/bignumber/lib/bignumber");
function validateAsset(asset, argument, errorPrefix) {
if (typeof asset !== 'string' || asset.length < 1) {
throw Error(errorPrefix + 'Argument `' + argument + '` must be a non-empty string.');
}
var assetIsVToken = asset[0] === 'v';
var vTokenName = assetIsVToken ? asset : 'v' + asset;
var vTokenAddress = constants_1.address[this._network.name][vTokenName];
var underlyingName = assetIsVToken ? asset.slice(1, asset.length) : asset;
var underlyingAddress = constants_1.address[this._network.name][underlyingName];
if ((!constants_1.cTokens.includes(vTokenName) || !constants_1.underlyings.includes(underlyingName)) &&
!constants_1.opfAssets.includes(underlyingName)) {
throw Error(errorPrefix + 'Argument `' + argument + '` is not supported.');
}
var underlyingDecimals = constants_1.decimals[underlyingName];
// The open price feed reveals BTC, not WBTC.
underlyingName = underlyingName === 'WBTC' ? 'BTC' : underlyingName;
return [assetIsVToken, vTokenName, vTokenAddress, underlyingName, underlyingAddress, underlyingDecimals];
}
function vTokenExchangeRate(vTokenAddress, vTokenName, underlyingDecimals) {
return __awaiter(this, void 0, void 0, function () {
var address, method, options, exchangeRateCurrent, mantissa, oneVTokenInUnderlying;
return __generator(this, function (_a) {
switch (_a.label) {
case 0:
address = vTokenAddress;
method = 'exchangeRateCurrent';
options = {
_compoundProvider: this._provider,
abi: vTokenName === constants_1.constants.vBNB ? constants_1.abi.vBNB : constants_1.abi.vBep20
};
return [4 /*yield*/, eth.read(address, method, [], options)];
case 1:
exchangeRateCurrent = _a.sent();
mantissa = 18 + underlyingDecimals - 8;
oneVTokenInUnderlying = exchangeRateCurrent / Math.pow(10, mantissa);
return [2 /*return*/, oneVTokenInUnderlying];
}
});
});
}
/**
* Gets an asset's price from the Venus Protocol open price feed. The price
* of the asset can be returned in any other supported asset value, including
* all vTokens and underlyings.
*
* @param {string} asset A string of a supported asset in which to find the
* current price.
* @param {string} [inAsset] A string of a supported asset in which to express
* the `asset` parameter's price. This defaults to USD.
*
* @returns {string} Returns a string of the numeric value of the asset.
*
* @example
* ```
* const venus = new Venus(window.ethereum);
* let price;
*
* (async function () {
*
* price = await venus.getPrice(Venus.BNB);
* console.log('BNB in USD', price);
*
* price = await venus.getPrice(Venus.SXP, Venus.USDC); // supports vTokens too
* console.log('SXP in USDC', price);
*
* })().catch(console.error);
* ```
*/
function getPrice(asset, inAsset) {
if (inAsset === void 0) { inAsset = constants_1.constants.USDC; }
return __awaiter(this, void 0, void 0, function () {
var errorPrefix, _a,
// eslint-disable-next-line @typescript-eslint/no-unused-vars
assetIsVToken, vTokenName, vTokenAddress, underlyingName, underlyingAddress, underlyingDecimals, _b,
// eslint-disable-next-line @typescript-eslint/no-unused-vars
inAssetIsVToken, inAssetVTokenName, inAssetVTokenAddress, inAssetUnderlyingName, inAssetUnderlyingAddress, inAssetUnderlyingDecimals, comptrollerAddress, oracleTrxOptions, priceOracleAddress, trxOptions, assetUnderlyingPrice, inAssetUnderlyingPrice, assetDecimal, inAssetDecimal, assetVTokensInUnderlying, inAssetVTokensInUnderlying, result, assetInOther, assetInOther, assetInOther, vTokensInUnderlying;
return __generator(this, function (_c) {
switch (_c.label) {
case 0: return [4 /*yield*/, helpers_1.netId(this)];
case 1:
_c.sent();
errorPrefix = 'Venus [getPrice] | ';
_a = validateAsset.bind(this)(asset, 'asset', errorPrefix), assetIsVToken = _a[0], vTokenName = _a[1], vTokenAddress = _a[2], underlyingName = _a[3], underlyingAddress = _a[4], underlyingDecimals = _a[5];
_b = validateAsset.bind(this)(inAsset, 'inAsset', errorPrefix), inAssetIsVToken = _b[0], inAssetVTokenName = _b[1], inAssetVTokenAddress = _b[2], inAssetUnderlyingName = _b[3], inAssetUnderlyingAddress = _b[4], inAssetUnderlyingDecimals = _b[5];
comptrollerAddress = constants_1.address[this._network.name].Comptroller;
oracleTrxOptions = {
_compoundProvider: this._provider,
abi: constants_1.abi.Comptroller
};
return [4 /*yield*/, eth.read(comptrollerAddress, 'oracle', [], oracleTrxOptions)];
case 2:
priceOracleAddress = _c.sent();
trxOptions = {
_compoundProvider: this._provider,
abi: constants_1.abi.PriceOracle
};
return [4 /*yield*/, eth.read(priceOracleAddress, 'getUnderlyingPrice', [vTokenAddress], trxOptions)];
case 3:
assetUnderlyingPrice = _c.sent();
return [4 /*yield*/, eth.read(priceOracleAddress, 'getUnderlyingPrice', [inAssetVTokenAddress], trxOptions)];
case 4:
inAssetUnderlyingPrice = _c.sent();
assetDecimal = constants_1.decimals[asset];
inAssetDecimal = constants_1.decimals[inAsset];
if ((assetDecimal - inAssetDecimal) > 0) {
assetUnderlyingPrice = assetUnderlyingPrice.mul(bignumber_1.BigNumber.from("10").pow(assetDecimal - inAssetDecimal));
}
else {
assetUnderlyingPrice = assetUnderlyingPrice.div(bignumber_1.BigNumber.from("10").pow(inAssetDecimal - assetDecimal));
}
if (!assetIsVToken) return [3 /*break*/, 6];
return [4 /*yield*/, vTokenExchangeRate.bind(this)(vTokenAddress, vTokenName, underlyingDecimals)];
case 5:
assetVTokensInUnderlying = _c.sent();
_c.label = 6;
case 6:
if (!inAssetIsVToken) return [3 /*break*/, 8];
return [4 /*yield*/, vTokenExchangeRate.bind(this)(inAssetVTokenAddress, inAssetVTokenName, inAssetUnderlyingDecimals)];
case 7:
inAssetVTokensInUnderlying = _c.sent();
_c.label = 8;
case 8:
if (!assetIsVToken && !inAssetIsVToken) {
result = assetUnderlyingPrice / inAssetUnderlyingPrice;
}
else if (assetIsVToken && !inAssetIsVToken) {
assetInOther = assetUnderlyingPrice / inAssetUnderlyingPrice;
result = assetInOther * assetVTokensInUnderlying;
}
else if (!assetIsVToken && inAssetIsVToken) {
assetInOther = assetUnderlyingPrice / inAssetUnderlyingPrice;
result = assetInOther / inAssetVTokensInUnderlying;
}
else {
assetInOther = assetUnderlyingPrice / inAssetUnderlyingPrice;
vTokensInUnderlying = assetInOther / assetVTokensInUnderlying;
result = inAssetVTokensInUnderlying * vTokensInUnderlying;
}
return [2 /*return*/, result];
}
});
});
}
exports.getPrice = getPrice;
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