fix bug with extra precision

package.json

@@ -1,6 +1,6 @@
 {
   "name": "gas-price-oracle",
-  "version": "0.2.0",
+  "version": "0.2.2",
   "description": "Gas Price Oracle library for Ethereum dApps.",
   "main": "lib/index.js",
   "homepage": "https://github.com/peppersec/gas-price-oracle",

src/config.ts

@@ -55,6 +55,17 @@ const gasNow: OffChainOracle = {
   additionalDataProperty: 'data',
 };
 
+const anyblock: OffChainOracle = {
+  name: 'anyblock',
+  url: 'https://api.anyblock.tools/ethereum/latest-minimum-gasprice',
+  instantPropertyName: 'instant',
+  fastPropertyName: 'fast',
+  standardPropertyName: 'standard',
+  lowPropertyName: 'slow',
+  denominator: 1,
+  additionalDataProperty: null,
+};
+
 const chainlink: OnChainOracle = {
   name: 'chainlink',
   callData: '0x50d25bcd',
@@ -64,6 +75,7 @@ const chainlink: OnChainOracle = {
 
 export const offChainOracles: { [key: string]: OffChainOracle } = {
   ethgasstation,
+  anyblock,
   gasNow,
   poa,
   etherchain,

src/index.ts

@@ -41,7 +41,7 @@ export class GasPriceOracle {
         standard: parseFloat(gas[standardPropertyName]) / denominator,
         low: parseFloat(gas[lowPropertyName]) / denominator,
       };
-      return gasPrices;
+      return this.normalize(gasPrices);
     } else {
       throw new Error(`Fetch gasPrice from ${name} oracle failed. Trying another one...`);
     }
@@ -108,7 +108,25 @@ export class GasPriceOracle {
       const middle = Math.floor(allPrices.length / 2);
       medianGasPrice[type] = isEven ? (allPrices[middle - 1] + allPrices[middle]) / 2.0 : allPrices[middle];
     }
-    return medianGasPrice;
+    return this.normalize(medianGasPrice);
+  }
+  /**
+   * Normalizes GasPrice values to Gwei. No more than 9 decimals basically
+   * @param GasPrice _gas
+   */
+  normalize(_gas: GasPrice): GasPrice {
+    const format = {
+      decimalSeparator: '.',
+      groupSeparator: '',
+    };
+    const decimals = 9;
+
+    const gas: GasPrice = { ..._gas };
+    for (const type of Object.keys(gas) as Array<keyof GasPrice>) {
+      gas[type] = Number(new BigNumber(gas[type]).toFormat(decimals, format));
+    }
+
+    return gas;
   }
 
   async fetchGasPricesOnChain(): Promise<number> {

tests/index.test.ts

@@ -1,9 +1,9 @@
 /* eslint-disable @typescript-eslint/no-non-null-assertion */
 /* eslint-disable @typescript-eslint/no-var-requires */
-import { GasPrice } from '../src/types';
+import { GasPrice, OffChainOracle } from '../src/types';
 import mockery from 'mockery';
 import chai from 'chai';
-import { onChainOracles } from '../src/config';
+import { onChainOracles, offChainOracles } from '../src/config';
 
 import { GasPriceOracle } from '../src/index';
 chai.use(require('chai-as-promised'));
@@ -204,6 +204,29 @@ 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);
+
+        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);
+      }
+    }
+  });
+});
+
 after('after', function () {
   after(function () {
     mockery.disable();