fix: update oracles

README.md

@@ -9,10 +9,8 @@ A library that has a collection of onchain and offchain gas price oracle URLs
 Current offchain list:
 
 - https://ethgasstation.info/json/ethgasAPI.json
-- https://gas-oracle.zoltu.io/
-- https://www.etherchain.org/api/gasPriceOracle
-- https://gasprice.poa.network/
-- https://www.gasnow.org/api/v3/gas/price
+- https://etherchain.org/api/gasnow
+- https://blockscout.com/eth/mainnet/api/v1/gas-price-oracle
 
 Current onchain list:
 
@@ -22,7 +20,13 @@ Current onchain list:
 
 Current offchain list:
 
-- https://bscgas.info/
+- https://ztake.org/
+
+### xDAI Chain
+
+Current offchain list:
+
+- https://blockscout.com/xdai/mainnet/api/v1/gas-price-oracle
 
 ### Polygon (Matic) Network
 
@@ -30,6 +34,18 @@ Current offchain list:
 
 - https://gasstation-mainnet.matic.network/
 
+### Arbitrum One
+
+Current offchain list:
+
+- https://ztake.org/
+
+### Avalanche Mainnet
+
+Current offchain list:
+
+- https://ztake.org/
+
 ## Installation
 
 `npm i gas-price-oracle`

package.json

@@ -1,6 +1,6 @@
 {
   "name": "gas-price-oracle",
-  "version": "0.3.3",
+  "version": "0.4.1",
   "description": "Gas Price Oracle library for Ethereum dApps.",
   "main": "lib/index.js",
   "homepage": "https://github.com/peppersec/gas-price-oracle",

src/config/arbitrum.ts

@@ -0,0 +1,23 @@
+import { OffChainOracle, OffChainOracles, OnChainOracles } from '../types';
+
+const ztake: OffChainOracle = {
+  name: 'ztake',
+  url: 'https://blockchains.ztake.org/api/h6WnmwNqw9CAJHzej5W4gD6LZ9n7v8EK/gasprice/arb/',
+  instantPropertyName: 'percentile_90',
+  fastPropertyName: 'percentile_80',
+  standardPropertyName: 'percentile_60',
+  lowPropertyName: 'percentile_30',
+  denominator: 1,
+  additionalDataProperty: null,
+};
+
+export const offChainOracles: OffChainOracles = {
+  ztake,
+};
+
+export const onChainOracles: OnChainOracles = {};
+
+export default {
+  offChainOracles,
+  onChainOracles,
+};

src/config/avalanche.ts

@@ -0,0 +1,23 @@
+import { OffChainOracle, OffChainOracles, OnChainOracles } from '../types';
+
+const ztake: OffChainOracle = {
+  name: 'ztake',
+  url: 'https://blockchains.ztake.org/api/h6WnmwNqw9CAJHzej5W4gD6LZ9n7v8EK/gasprice/avax/',
+  instantPropertyName: 'percentile_90',
+  fastPropertyName: 'percentile_80',
+  standardPropertyName: 'percentile_60',
+  lowPropertyName: 'percentile_30',
+  denominator: 1,
+  additionalDataProperty: null,
+};
+
+export const offChainOracles: OffChainOracles = {
+  ztake,
+};
+
+export const onChainOracles: OnChainOracles = {};
+
+export default {
+  offChainOracles,
+  onChainOracles,
+};

src/config/bsc.ts

@@ -0,0 +1,23 @@
+import { OffChainOracle, OffChainOracles, OnChainOracles } from '../types';
+
+const ztake: OffChainOracle = {
+  name: 'ztake',
+  url: 'https://blockchains.ztake.org/api/h6WnmwNqw9CAJHzej5W4gD6LZ9n7v8EK/gasprice/bsc/',
+  instantPropertyName: 'percentile_90',
+  fastPropertyName: 'percentile_80',
+  standardPropertyName: 'percentile_60',
+  lowPropertyName: 'percentile_30',
+  denominator: 1,
+  additionalDataProperty: null,
+};
+
+export const offChainOracles: OffChainOracles = {
+  ztake,
+};
+
+export const onChainOracles: OnChainOracles = {};
+
+export default {
+  offChainOracles,
+  onChainOracles,
+};

src/config/index.ts

@@ -1,16 +1,26 @@
 import { NetworkConfig } from '../types';
+
 import mainnetOracles from './mainnet';
-import binanceOracles from './binance';
+import bscOracles from './bsc';
+import xdaiOracles from './xdai';
 import polygonOracles from './polygon';
+import arbitrumOracles from './arbitrum';
+import avalancheOracles from './avalanche';
 
 export enum ChainId {
   MAINNET = 1,
-  BINANCE = 56,
+  BSC = 56,
+  XDAI = 100,
   POLYGON = 137,
+  ARBITRUM = 42161,
+  AVALANCHE = 43114,
 }
 
-export const networks: NetworkConfig = {
+export const NETWORKS: NetworkConfig = {
   [ChainId.MAINNET]: mainnetOracles,
-  [ChainId.BINANCE]: binanceOracles,
+  [ChainId.BSC]: bscOracles,
+  [ChainId.XDAI]: xdaiOracles,
   [ChainId.POLYGON]: polygonOracles,
+  [ChainId.ARBITRUM]: arbitrumOracles,
+  [ChainId.AVALANCHE]: avalancheOracles,
 };

src/config/mainnet.ts

@@ -11,50 +11,28 @@ const ethgasstation: OffChainOracle = {
   additionalDataProperty: null,
 };
 
-const zoltu: OffChainOracle = {
-  name: 'zoltu',
-  url: 'https://gas-oracle.zoltu.io/',
-  instantPropertyName: 'percentile_99',
-  fastPropertyName: 'percentile_90',
-  standardPropertyName: 'percentile_60',
-  lowPropertyName: 'percentile_30',
-  denominator: 1,
-  additionalDataProperty: null,
-};
-
 const etherchain: OffChainOracle = {
   name: 'etherchain',
-  url: 'https://www.etherchain.org/api/gasPriceOracle',
-  instantPropertyName: 'fastest',
-  fastPropertyName: 'fast',
-  standardPropertyName: 'standard',
-  lowPropertyName: 'safeLow',
-  denominator: 1,
-  additionalDataProperty: null,
-};
-
-const poa: OffChainOracle = {
-  name: 'poa',
-  url: 'https://gasprice.poa.network/',
-  instantPropertyName: 'instant',
-  fastPropertyName: 'fast',
-  standardPropertyName: 'standard',
-  lowPropertyName: 'slow',
-  denominator: 1,
-  additionalDataProperty: null,
-};
-
-const gasNow: OffChainOracle = {
-  name: 'gasNow',
-  url: 'https://www.gasnow.org/api/v3/gas/price?utm_source=gas-price-oracle',
+  url: 'https://etherchain.org/api/gasnow',
   instantPropertyName: 'rapid',
   fastPropertyName: 'fast',
   standardPropertyName: 'standard',
   lowPropertyName: 'slow',
-  denominator: 1e9,
+  denominator: 1,
   additionalDataProperty: 'data',
 };
 
+const blockscout: OffChainOracle = {
+  name: 'blockscout',
+  url: 'https://blockscout.com/eth/mainnet/api/v1/gas-price-oracle',
+  instantPropertyName: 'fast',
+  fastPropertyName: 'average',
+  standardPropertyName: 'slow',
+  lowPropertyName: 'slow',
+  denominator: 1,
+  additionalDataProperty: null,
+};
+
 const anyblock: OffChainOracle = {
   name: 'anyblock',
   url: 'https://api.anyblock.tools/ethereum/latest-minimum-gasprice',
@@ -76,10 +54,8 @@ const chainlink: OnChainOracle = {
 export const offChainOracles: OffChainOracles = {
   ethgasstation,
   anyblock,
-  gasNow,
-  poa,
+  blockscout,
   etherchain,
-  zoltu,
 };
 
 export const onChainOracles: OnChainOracles = {

src/config/xdai.ts

@@ -1,18 +1,18 @@
 import { OffChainOracle, OffChainOracles, OnChainOracles } from '../types';
 
-const bscgas: OffChainOracle = {
-  name: 'bscgas',
-  url: 'https://bscgas.info/gas',
-  instantPropertyName: 'instant',
-  fastPropertyName: 'fast',
-  standardPropertyName: 'standard',
+const blockscout: OffChainOracle = {
+  name: 'blockscout',
+  url: 'https://blockscout.com/xdai/mainnet/api/v1/gas-price-oracle',
+  instantPropertyName: 'fast',
+  fastPropertyName: 'average',
+  standardPropertyName: 'slow',
   lowPropertyName: 'slow',
   denominator: 1,
   additionalDataProperty: null,
 };
 
 export const offChainOracles: OffChainOracles = {
-  bscgas,
+  blockscout,
 };
 
 export const onChainOracles: OnChainOracles = {};

src/index.ts

@@ -1,5 +1,8 @@
 import axios from 'axios';
-import { ChainId, networks } from './config';
+import BigNumber from 'bignumber.js';
+
+import { ChainId, NETWORKS } from './config';
+
 import {
   Config,
   Options,
@@ -10,7 +13,6 @@ import {
   OnChainOracles,
   OffChainOracles,
 } from './types';
-import BigNumber from 'bignumber.js';
 
 const defaultFastGas = 22;
 export class GasPriceOracle {
@@ -34,9 +36,13 @@ export class GasPriceOracle {
       Object.assign(this.configuration, options);
     }
 
-    const { offChainOracles, onChainOracles } = networks[this.configuration.chainId];
-    this.offChainOracles = { ...offChainOracles };
-    this.onChainOracles = { ...onChainOracles };
+    const network = NETWORKS[this.configuration.chainId];
+
+    if (network) {
+      const { offChainOracles, onChainOracles } = network;
+      this.offChainOracles = { ...offChainOracles };
+      this.onChainOracles = { ...onChainOracles };
+    }
   }
 
   async askOracle(oracle: OffChainOracle): Promise<GasPrice> {
@@ -181,19 +187,65 @@ export class GasPriceOracle {
     throw new Error('All oracles are down. Probably a network error.');
   }
 
+  async fetchGasPriceFromRpc(): Promise<number> {
+    const rpcUrl = this.configuration.defaultRpc;
+    const body = {
+      jsonrpc: '2.0',
+      id: 1337,
+      method: 'eth_gasPrice',
+      params: [],
+    };
+    try {
+      // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+      const response = await axios.post(rpcUrl!, body, { timeout: this.configuration.timeout });
+      if (response.status === 200) {
+        const { result } = response.data;
+        let fastGasPrice = new BigNumber(result);
+        if (fastGasPrice.isZero()) {
+          throw new Error(`Default RPC provides corrupted values`);
+        }
+        fastGasPrice = fastGasPrice.div(1e9);
+        return fastGasPrice.toNumber();
+      }
+
+      throw new Error(`Fetch gasPrice from default RPC failed..`);
+    } catch (e) {
+      console.error(e.message);
+      throw new Error('Default RPC is down. Probably a network error.');
+    }
+  }
+
   async gasPrices(fallbackGasPrices?: GasPrice, median = true): Promise<GasPrice> {
     this.lastGasPrice = this.lastGasPrice || fallbackGasPrices || this.configuration.defaultFallbackGasPrices;
-    try {
-      this.lastGasPrice = median
-        ? await this.fetchMedianGasPriceOffChain()
-        : await this.fetchGasPricesOffChain();
-      return this.lastGasPrice;
-    } catch (e) {
-      console.log('Failed to fetch gas prices from offchain oracles. Trying onchain ones...');
+
+    if (Object.keys(this.offChainOracles).length > 0) {
+      try {
+        this.lastGasPrice = median
+          ? await this.fetchMedianGasPriceOffChain()
+          : await this.fetchGasPricesOffChain();
+        return this.lastGasPrice;
+      } catch (e) {
+        console.log('Failed to fetch gas prices from offchain oracles. Trying onchain ones...');
+      }
+    }
+
+    if (Object.keys(this.onChainOracles).length > 0) {
+      try {
+        const fastGas = await this.fetchGasPricesOnChain();
+        this.lastGasPrice = {
+          instant: fastGas * 1.3,
+          fast: fastGas,
+          standard: fastGas * 0.85,
+          low: fastGas * 0.5,
+        };
+        return this.lastGasPrice;
+      } catch (e) {
+        console.log('Failed to fetch gas prices from onchain oracles. Trying from default RPC...');
+      }
     }
 
     try {
-      const fastGas = await this.fetchGasPricesOnChain();
+      const fastGas = await this.fetchGasPriceFromRpc();
       this.lastGasPrice = {
         instant: fastGas * 1.3,
         fast: fastGas,
@@ -202,7 +254,7 @@ export class GasPriceOracle {
       };
       return this.lastGasPrice;
     } catch (e) {
-      console.log('Failed to fetch gas prices from onchain oracles. Last known gas will be returned');
+      console.log('Failed to fetch gas prices from default RPC. Last known gas will be returned');
     }
     return this.lastGasPrice;
   }

tests/index.test.ts

@@ -1,12 +1,16 @@
 /* eslint-disable @typescript-eslint/no-non-null-assertion */
 /* eslint-disable @typescript-eslint/no-var-requires */
-import { GasPrice, OffChainOracle } from '../src/types';
-import mockery from 'mockery';
 import chai from 'chai';
+import mockery from 'mockery';
 
+import { ChainId, NETWORKS } from '../src/config';
 import { GasPriceOracle } from '../src/index';
+
+import { GasPrice, OffChainOracle } from '../src/types';
+
 chai.use(require('chai-as-promised'));
 chai.should();
+
 let oracle = new GasPriceOracle();
 let { onChainOracles, offChainOracles } = oracle;
 
@@ -119,6 +123,37 @@ describe('fetchGasPricesOnChain', function () {
   });
 });
 
+describe('fetchGasPriceFromRpc', function () {
+  it('should work', async function () {
+    const gas: number = await oracle.fetchGasPriceFromRpc();
+    gas.should.be.a('number');
+    gas.should.be.above(1);
+    gas.should.not.be.equal(0);
+  });
+
+  it('should work with custom rpc', async function () {
+    const rpc = 'https://ethereum-rpc.trustwalletapp.com';
+    const oracle = new GasPriceOracle({ defaultRpc: rpc });
+    oracle.configuration.defaultRpc.should.be.equal(rpc);
+    const gas: number = await oracle.fetchGasPriceFromRpc();
+
+    gas.should.be.a('number');
+
+    gas.should.be.above(1);
+    gas.should.not.be.equal(0);
+  });
+
+  it('should throw if default rpc is down', async function () {
+    mockery.enable({ useCleanCache: true, warnOnUnregistered: false });
+    const { GasPriceOracle } = require('../src/index');
+    oracle = new GasPriceOracle();
+    await oracle
+      .fetchGasPriceFromRpc()
+      .should.be.rejectedWith('Default RPC is down. Probably a network error.');
+    mockery.disable();
+  });
+});
+
 describe('gasPrice', function () {
   it('should work', async function () {
     const gas: GasPrice = await oracle.gasPrices();
@@ -206,25 +241,34 @@ describe('fetchMedianGasPriceOffChain', function () {
 });
 
 describe('askOracle', function () {
-  it('all oracles should answer', async function () {
-    for (const o of Object.values(offChainOracles) as Array<OffChainOracle>) {
-      try {
-        const gas: GasPrice = await oracle.askOracle(o);
+  const chains = Object.keys(NETWORKS).map(id => Number(id));
 
-        gas.instant.should.be.a('number');
-        gas.fast.should.be.a('number');
-        gas.standard.should.be.a('number');
-        gas.low.should.be.a('number');
+  chains.forEach(chainId => {
+    describe(`all ${ChainId[chainId]} oracles should answer`, function () {
+      oracle = new GasPriceOracle({ chainId });
+      ({ offChainOracles } = oracle);
 
-        gas.instant.should.be.at.least(gas.fast); // greater than or equal to the given number.
-        gas.fast.should.be.at.least(gas.standard);
-        gas.standard.should.be.at.least(gas.low);
-        gas.low.should.not.be.equal(0);
-      } catch (e) {
-        console.error(`Failed to get data from ${o.name} oracle`);
-        throw new Error(e);
+      for (const o of Object.values(offChainOracles) as Array<OffChainOracle>) {
+        it(`check ${o.name}`, async function () {
+          try {
+            const gas: GasPrice = await oracle.askOracle(o);
+
+            gas.instant.should.be.a('number');
+            gas.fast.should.be.a('number');
+            gas.standard.should.be.a('number');
+            gas.low.should.be.a('number');
+
+            gas.instant.should.be.at.least(gas.fast); // greater than or equal to the given number.
+            gas.fast.should.be.at.least(gas.standard);
+            gas.standard.should.be.at.least(gas.low);
+            gas.low.should.not.be.equal(0);
+          } catch (e) {
+            console.error(`Failed to get data from ${o.name} oracle`);
+            throw new Error(e);
+          }
+        });
       }
-    }
+    });
   });
 });