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README.md

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+# Tornado oracles
+
+This is a library providing convenient and fast access to oracles for Tornado-specific transactions, for example, withdrawal via relayer or getting rate to ETH for tokens that used in Tornado pools
+
+### Installation
+
+<hr>
+
+* Create `.npmrc` file in project root with content `@tornado:registry=https://git.tornado.ws/api/packages/tornado-packages/npm/`
+* Run `npm i @tornado/tornado-oracles`
+
+
+
+### Import
+
+<hr>
+
+```typescript
+const {TornadoFeeOracleV5, TornadoFeeOracleV5, TokenPriceOracle} = require('@tornado/tornado-oracles')
+or
+import {TornadoFeeOracleV5, TornadoFeeOracleV5, TokenPriceOracle} from '@tornado/tornado-oracles'
+```
+
+
+
+### Usage
+
+<hr>
+
+##### Estimate withdrawal gas costs
+
+```typescript
+import { TornadoFeeOracleV5 } from '@tornado/tornado-oracles'
+
+const tx: TransactionData = {
+    to: tornadoProxyLightAddress,
+    data: poolInstance.methods.withdraw(...params).encodeABI(),
+    value: withdrawalProofArgs[5]
+}
+
+const feeOracle = new TornadoFeeOracleV5(1, "https://eth.llamarpc.com"); // First parameter - chain ID
+const withdrawalGas = await feeOracle.getGas(tx, "relayer_withdrawal");
+```
+
+##### Estimate gas price and gas limit to send transaction
+
+```typescript
+import { TornadoFeeOracleV5 } from '@tornado/tornado-oracles'
+
+const incompleteTx: TransactionData = {
+    to: tornadoProxyLightAddress,
+    data: poolInstance.methods.withdraw(...params).encodeABI(),
+    value: withdrawalProofArgs[5]
+}
+
+const feeOracle = new TornadoFeeOracleV5(1, "https://eth.llamarpc.com");
+const transactionType: TxType = "relayer_withdrawal";
+const gasPrice = await feeOracle.getGasPriceInHex(transactionType);
+const gasLimit = await feeOracle.getGasLimit(incompleteTx, transactionType);
+
+const tx: TransactionData = Object.assign({ gasPrice, gasLimit }, incompleteTx);
+```
+
+##### Get token prices (rate to ETH) for tokens that used in Tornado
+
+```typescript
+import { TokenPriceOracle } from '@tornado/tornado-oracles'
+
+const priceOracle = new TokenPriceOracle("https://eth.llamarpc.com");
+const tokenPrices = await priceOracle.fetchPrices();
+
+console.log(tokenPrices); // All prices in WEI
+/* 
+{
+  torn: '1653773547906175', 
+  dai: '603108348359886',
+  cdai: '13487984643748',
+  usdc: '601311723569085',
+  usdt: '602058974373161',
+  wbtc: '15696224089898846959'
+}
+*/
+```
+
+### License
+
+[MIT](LICENSE)