Update offchain oracles link, add mechanism to resolve structurized oracle JSON responses

README.md

@@ -8,12 +8,11 @@ This is a library with a collection of onchain and offchain gas price oracle URL
 
 Current offchain list:
 
-- https://ethgasstation.info/json/ethgasAPI.json
 - https://etherchain.org/api/gasnow
 
 Current onchain list:
 
-- [chainlink](https://etherscan.io/address/0x169e633a2d1e6c10dd91238ba11c4a708dfef37c#readContract)
+- [Chainlink aggregator](https://etherscan.io/address/0x169e633a2d1e6c10dd91238ba11c4a708dfef37c#readContract)
 
 ### Binance Smart Chain
 
@@ -25,13 +24,14 @@ Current offchain list:
 
 Current offchain list:
 
-- https://blockscout.com/xdai/mainnet/api/v1/gas-price-oracle
+- https://gnosis.blockscout.com/api/v1/gas-price-oracle
 
 ### Polygon (Matic) Network
 
 Current offchain list:
 
-- https://gasstation-mainnet.matic.network/
+- https://gasstation.polygon.technology/v2
+- https://matic-gas-station.tornado.ws
 
 ### Avalanche C Network
 

src/config/mainnet.ts

@@ -1,16 +1,5 @@
 import { OffChainOracle, OffChainOracles, OnChainOracle, OnChainOracles } from '@/services'
 
-const ethgasstation: OffChainOracle = {
-  name: 'ethgasstation',
-  url: 'https://ethgasstation.info/json/ethgasAPI.json',
-  instantPropertyName: 'fastest',
-  fastPropertyName: 'fast',
-  standardPropertyName: 'average',
-  lowPropertyName: 'safeLow',
-  denominator: 10,
-  additionalDataProperty: null,
-}
-
 const etherchain: OffChainOracle = {
   name: 'etherchain',
   url: 'https://etherchain.org/api/gasnow',
@@ -30,7 +19,6 @@ const chainlink: OnChainOracle = {
 }
 
 export const offChainOracles: OffChainOracles = {
-  ethgasstation,
   etherchain,
 }
 

src/config/polygon.ts

@@ -2,10 +2,21 @@ import { OffChainOracle, OffChainOracles, OnChainOracles } from '@/services'
 
 const maticGasStation: OffChainOracle = {
   name: 'maticGasStation',
-  url: 'https://gasstation-mainnet.matic.network',
+  url: 'https://gasstation.polygon.technology/v2',
-  instantPropertyName: 'fastest',
+  instantPropertyName: 'fast.maxFee',
-  fastPropertyName: 'fast',
+  fastPropertyName: 'fast.maxFee',
-  standardPropertyName: 'standard',
+  standardPropertyName: 'standard.maxFee',
+  lowPropertyName: 'safeLow.maxFee',
+  denominator: 1,
+  additionalDataProperty: null,
+}
+
+const tornadoMaticGasStation: OffChainOracle = {
+  name: 'tornadoMGasStation',
+  url: 'https://matic-gas-station.tornado.ws',
+  instantPropertyName: 'standard',
+  fastPropertyName: 'standard',
+  standardPropertyName: 'safeLow',
   lowPropertyName: 'safeLow',
   denominator: 1,
   additionalDataProperty: null,
@@ -13,6 +24,7 @@ const maticGasStation: OffChainOracle = {
 
 export const offChainOracles: OffChainOracles = {
   maticGasStation,
+  tornadoMaticGasStation,
 }
 
 export const onChainOracles: OnChainOracles = {}

src/config/xdai.ts

@@ -2,7 +2,7 @@ import { OffChainOracle, OffChainOracles, OnChainOracles } from '@/services'
 
 const blockscout: OffChainOracle = {
   name: 'blockscout',
-  url: 'https://blockscout.com/xdai/mainnet/api/v1/gas-price-oracle',
+  url: 'https://gnosis.blockscout.com/api/v1/gas-price-oracle',
   instantPropertyName: 'fast',
   fastPropertyName: 'average',
   standardPropertyName: 'slow',

src/services/legacy-gas-price/legacy.ts

@@ -16,6 +16,7 @@ import {
 
 import { ChainId, NETWORKS } from '@/config'
 import { RpcFetcher, NodeJSCache } from '@/services'
+import { resolvePropertyPath } from '@/utils'
 import { GWEI, DEFAULT_TIMEOUT, GWEI_PRECISION, DEFAULT_BLOCK_DURATION } from '@/constants'
 
 import { MULTIPLIERS, DEFAULT_GAS_PRICE } from './constants'
@@ -297,17 +298,17 @@ export class LegacyGasPriceOracle implements LegacyOracle {
     const response = await axios.get(url, { timeout: this.configuration.timeout })
 
     if (response.status === 200) {
-      const gas = additionalDataProperty ? response.data[additionalDataProperty] : response.data
+      const gas = resolvePropertyPath(response.data, additionalDataProperty)
 
-      if (Number(gas[fastPropertyName]) === 0) {
+      if (Number(resolvePropertyPath(gas, fastPropertyName)) === 0) {
         throw new Error(`${name} oracle provides corrupted values`)
       }
 
       const gasPrices: GasPrice = {
-        instant: parseFloat(gas[instantPropertyName]) / denominator,
+        instant: parseFloat(resolvePropertyPath(gas, instantPropertyName)) / denominator,
-        fast: parseFloat(gas[fastPropertyName]) / denominator,
+        fast: parseFloat(resolvePropertyPath(gas, fastPropertyName)) / denominator,
-        standard: parseFloat(gas[standardPropertyName]) / denominator,
+        standard: parseFloat(resolvePropertyPath(gas, standardPropertyName)) / denominator,
-        low: parseFloat(gas[lowPropertyName]) / denominator,
+        low: parseFloat(resolvePropertyPath(gas, lowPropertyName)) / denominator,
       }
       return LegacyGasPriceOracle.normalize(gasPrices)
     } else {

src/utils/index.ts

@@ -5,4 +5,43 @@ const sleep = (time: number): Promise<boolean> => {
   return new Promise((res) => setTimeout(() => res(true), time))
 }
 
-export { sleep }
+/**
+ * Returns the recursively resolved value of the object's subproperty given the properties path, separated by dots.
+ * If properties path is null, undefined or an empty string - returns the object itself
+ * @param obj - The object, from which get property or subproperty
+ * @param propertiesInString - Property name or properties chained string, like 'user.email.domain'
+ * @returns The value of the subproperty by path or object itself
+ *
+ * @example
+ *
+ * ### Object
+ * ```ts
+ * const x = {
+ *    y: {
+ *      z: 11
+ *    }
+ * };
+ * ```
+ *
+ * ### Property path in object
+ * ```ts
+ * const propertyPath = 'y.z';
+ * ```
+ *
+ * ### Usage
+ * ```ts
+ * const subpropertyValue = resolvePropertyPath(x, propertyPath);
+ * ```
+ *
+ * ### Result (subproperty value)
+ * ```ts
+ * 11
+ * ```
+ */
+const resolvePropertyPath = (obj: object, propertyPath: string | undefined | null): any => {
+  const properties = propertyPath?.split('.') || []
+
+  return properties.reduce((curr: { [key: string]: any }, nextProperty: string) => curr[nextProperty], obj)
+}
+
+export { sleep, resolvePropertyPath }